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REPORT OF FOOT STEP POWER GENERATION PROJECT

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1
CHAPTER – 1
INTRODUCTION
1.1Power Generation
I would not be wrong to say that the sun was supplying all the energy needs...
2
position due to negating springs provided in the device. The upper plate is mounted on two
springs, the weight impact is...
3
therefore, harnessing the gigantic inexhaustible solar energy source reduces the dependence on
fossil fuels. For the env...
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REPORT OF FOOT STEP POWER GENERATION PROJECT

  1. 1. 1 CHAPTER – 1 INTRODUCTION 1.1Power Generation I would not be wrong to say that the sun was supplying all the energy needs of man either directly or indirectly and that man was using only renewable sources of energy. Question that every time comes before every country i.e. the need of non conventional energy sources or systems. Why we need these systems and the answers are the growing consumption of energy has resulted in the country becoming increasingly dependent on fossil fuels such as coal, oil & gas. Rising prices of oil and gases and their potential shortages have raised uncertainties about the security of energy supply in future, which has serious repercussions on the growth of the national economy. The main factor is increasing use of fossil fuels also causes serious environmental problems. Man has needed and used energy at an increasing rate for his sustenance and well being ever since he came on the earth a few million years ago. Primitive man required energy primarily in the form of food. He derived this for cooking as well as for keeping himself warm. With the passage of time, man started to cultivate land for agriculture. He added a new dimension to the use of energy by domesticating and training animals to work for him. With further demand for energy, man began to use the wind for sailing ships and for driving windmills, and the force of falling water to turn water for sailing ships and for driving windmills, and the force of falling water to turn water wheels. Till this time, it by eating plants or animals, which he hunted. Subsequently he discovered fire and his energy needs increased as he started to make use of wood and other bio mass to supply the energy needs Hence there is primary need to use renewable energy sources like solar, wind, tidal, biomas and energy from waste material. Now let us come to its some working principle, this device if embedded in footsteps of railway platforms, city malls, city footpaths e.t.c. can convert the weight impact of people into electrical energy. When a pedestrian will step on the top plate of this device, the plate will go down and this downward motion results in rotation of the shaft of the alternator which produces electrical energy. After removal of force the top plate returns to its original position due to springs. 1.2BASIC PRINCIPLE The downward movement of the plate results in rotation of the shaft of an electrical alternator, fitted in the device, to produce electrical energy. The top plate reverts back to its original
  2. 2. 2 position due to negating springs provided in the device. The upper plate is mounted on two springs, the weight impact is converted into electrical power with proper control unit. The spring and rack & pinion arrangement is fixed below the foot step which is mounted on base. Spring system is used for return mechanism of upper plate after release of load. The shaft along with pinion is supported by end bearings. One end is Foot Step Power Generation connected with small belt pulley system and on the other end a flywheel is mounted. The dc generator is rotated with the help of this belt & pulley arrangement. The flywheel is used here to maintain and increase the rpm of smaller pulley arrangement, the generator is used here is 12Volt permanent magnet DC generator. The terminal of DC generator is connected to lightning LEDs. 1.3NEED FOR NON-CONVENTIONAL ENERGY: Fuel deposit in the will soon deplete by the end of 2020Fuel scarcity will be maximum. Country like India may not have the chance to use petroleum products. Keeping this dangerous situation in mind we tried to make use of nonpollutant natural resource of petrol energy. The creation of new source of perennial environmentally acceptable, low cost electrical energy as a replacement for energy from rapidly depleting resources of fossil fuels is the fundamental need for the survival of mankind. We have only about 25 years of oil reserves and 75 – 100 years of coal reserves. Resort to measure beginning of coal in thermal electric stations to serve the population would result in global elementic change in leading to worldwide drought and decertification. The buzzards of nuclear electric-stations are only to will. Now electric power beamed directly by micro-wave for orbiting satellite. Solar power stations (s.p.s) provide a cost-effective solution even though work on solar photo voltaic and solar thermo electric energy sources has been extensively pursued by many countries. Earth based solar stations suffer certain basic limitations. It is not possible to consider such systems and meeting continuous uninterrupted concentrated base load electric power requirements. Energy plays an important role in the material, social and cultural life of man kind. The energy needs are increasing day by day. This is the result of population growth and increase in the standard of living which is directly proportional to energy consumption. As we know that mankind will be never lacking in energy. Today, it is liquid fluid, tomorrow it may be uranium with an element of risk. Risk exists where ever there is human activity and production of energy. Just as the supply of fossil fuel is finite thus there will be the supply of uranium. Perhaps, uranium would be exhausted quickly if it is used on a large scale .It is
  3. 3. 3 therefore, harnessing the gigantic inexhaustible solar energy source reduces the dependence on fossil fuels. For the environmental concerned, the solar energy harnessing system offers advantages in that, it emits no pollutants in to the atmosphere as they are with the combustion of fossil fuels. Thus, as a long term option solar energy system can be considered as an alternate to all the finite fuel system. Therefore, there is no energy shortage today nor will there be in the near future. The lifting of water for drinking or irrigation purposes is of great Impor- tance in widely distributed villages with little or no rural electrification and where underground water is available. Solar energy is converted to mechanical energy to drive small water pumps it would be of great help to the rural inhibitions. In our project we use solar photo voltaic cells for pumping water. The photo voltaic modules convert sunlight direct to electricity which is used to run a dc motor pump for bailing of water. It consists of solar photo voltaic modules, power conditioner to protect storage batteries from over charging during non-sun shine and a dc water pump. 1.4FOOT STEP ARRANGEMENT This is made up of mild steel. The complete set up is fixed in this model FOOT STEP. The two L-shapes frame is fixed in the above two ends of the track. Bellow this lshapes window, the actual power generation arrangement is constructed. This L-shapes window pushes the rack when the time of train wheelmoving on these arrangement. Fig.-A
  4. 4. 4 CHAPTER -2 MAIN PARTS MAIN PARTS OF POWER GENRATION BY FOOT STEP:  BATTERY  SHAFT  SPRING  BEARING  GEAR  RACK PINION  LED LIGHT  PULLEY  BELT  DYNAMO  DIODE 2.1BATTERY: Battery (electricity), an array of electrochemical cells for electricity storage, either individually linked or individually linked and housed in a single unit. An electrical battery is a combination of one or more electrochemical cells, used to convert stored chemical energy into electrical energy. Batteries may be used once and discarded, or recharged for years as in standby power applications. Miniature cells are used to power devices such as hearing aids and wristwatches; larger batteries provide standby power for telephone exchanges or computer data centers. Lead-acid batteries are the most common in PV systems because their initial cost is lower and because they are readily available nearly everywhere in the world. There are many different sizes and designs of lead-acid batteries, but the most important designation is that they are deep cycle batteries. Lead-acid batteries are available in both wet-cell (requires maintenance) and sealed no- maintenance versions. Lead acid batteries are reliable and cost effective with an exceptionally long life. The Lead acid batteries have high reliability because of their ability to withstand overcharge, over discharge vibration and shock. The use of special sealing techniques ensures that our batteries are leak proof and non-spoilable. The batteries have exceptional charge acceptance, large electrolyte volume and low self-discharge, Which make them ideal as zero- maintenance batteries lead acid batteries Are manufactured/ tested using CAD (Computer Aided Design). These batteries are used in Inverter & UPS Systems and have the proven ability to perform under extreme conditions. The batteries have electrolyte volume, use PE Separators and are sealed in sturdy containers, which give them excellent protection against leakage and corrosion.
  5. 5. 5 Secondary:Secondary batteries, also known as secondary cells, or rechargeable batteries, must be charged before first use; they are usually assembled with active materials in the discharged state. Rechargeable batteries are (re)charged by applying electric current, which reverses the chemical reactions that occur during discharge/use. Devices to supply the appropriate current are called chargers. The oldest form of rechargeable battery is the lead–acid battery, which are widely used in automotive and boating applications. This technology contains liquid electrolyte in an unsealed container, requiring that the battery be kept upright and the area well ventilated to ensure safety. Fig.-B 2.2SHAFT: A shaft is a rotating machine element, usually circular in cross section, which is used to transmit power from one part to another, or from a machine which produces power to a machine which absorbs power. The various members such as pulleys and gears are mounted on it. Types They are mainly classified into two types:-  Transmission shafts are used to transmit power between the source and the machine absorbing power; e.g. counter shafts and line shafts.
  6. 6.  Machine shafts are the integral part of the Here, we are using transmission shafts which is used to transmit power frm gears arrangemen the dynamo. Materials: The material used for ordinary shafts is such as nickel, nickel-chromium formed by hot rolling and finished to size by Stresses The following stresses are induced in the shafts. 1. Shear stresses due to the transmission of 2. Bending stresses (tensile elements like gears and pulleys 3. Stresses due to combined 2.3SPRING: A spring is an elastic object used to store mechanical spring steel. There are a large number of spring designs; in everyday usage the term often re to coil springs. When a spring is compressed or stretched from its resting position, it exerts an opposing force approximately proportional to its change in length (this approximation breaks down for larger deflections). The rate or spring constant of a spring is the change in the exerts, divided by the change in versus deflection curve. An extension 6 Machine shafts are the integral part of the machine itself; e.g. crankshaft. Here, we are using transmission shafts which is used to transmit power frm gears arrangemen The material used for ordinary shafts is mild steel. When high strength is required, an chromium or chromium-vanadium steel is used. Shafts are generally shed to size by cold drawing or turning and grinding Fig.-C are induced in the shafts. due to the transmission of torque (due to torsional load). tensile or compressive) due to the forces acting upon the machine pulleys as well as the self weight of the shaft. Stresses due to combined torsional and bending loads. object used to store mechanical energy. Springs are usually made out of . There are a large number of spring designs; in everyday usage the term often re When a spring is compressed or stretched from its resting position, it exerts an oximately proportional to its change in length (this approximation breaks down for larger deflections). The rate or spring constant of a spring is the change in the e change in deflection of the spring. That is, it is the gradient extension or compression spring's rate is expressed in units of force . Here, we are using transmission shafts which is used to transmit power frm gears arrangement to . When high strength is required, an alloy steel Shafts are generally grinding. ) due to the forces acting upon the machine . Springs are usually made out of . There are a large number of spring designs; in everyday usage the term often refers When a spring is compressed or stretched from its resting position, it exerts an oximately proportional to its change in length (this approximation breaks down for larger deflections). The rate or spring constant of a spring is the change in the force it gradient of the force spring's rate is expressed in units of force
  7. 7. 7 divided by distance, for example lbf/in or N/m. A torsion spring is a spring that works by twisting; when it is twisted about its axis by an angle, it produces a torque proportional to the angle. A torsion spring's rate is in units of torque divided by angle, such as N·m/rad or ft·lbf/degree. The inverse of spring rate is compliance, that is: if a spring has a rate of 10 N/mm, it has a compliance of 0.1 mm/N. The stiffness (or rate) of springs in parallel is additive, as is the compliance of springs in series. Springs are made from a variety of elastic materials, the most common being spring steel. Small springs can be wound from pre-hardened stock, while larger ones are made from annealed steel and hardened after fabrication. Some non-ferrous metals are also used including phosphor bronze and titanium for parts requiring corrosion resistance and beryllium copper for springs carrying electrical current (because of its low electrical resistance). Springs can be classified depending on how the load force is applied to them:  Tension/extension spring – the spring is designed to operate with a tension load, so the spring stretches as the load is applied to it.  Compression spring – is designed to operate with a compression load, so the spring gets shorter as the load is applied to it.  Torsion spring – unlike the above types in which the load is an axial force, the load applied to a torsion spring is a torque or twisting force, and the end of the spring rotates through an angle as the load is applied.  Constant spring - supported load will remain the same throughout deflection cycle[5]  Variable spring - resistance of the coil to load varies during compression[6] They can also be classified based on their shape:  Coil spring – this type is made of a coil or helix of round wire.  Flat spring – this type is made of a flat spring steel.  Machined spring – this type of spring is manufactured by machining bar stock with a lathe and/or milling operation rather than a coiling operation. Since it is machined, the spring may incorporate features in addition to the elastic element. Machined springs can be made in the typical load cases of compression/extension, torsion, etc.  Serpentine spring - a zig-zag of thick wire - often used in modern upholstery/furniture The most common types of spring are:  Cantilever spring – a spring which is fixed only at one end.  Coil spring or helical spring – a spring (made by winding a wire around a cylinder) is of two types: o Tension or extension springs are designed to become longer under load. Their turns (loops) are normally touching in the unloaded position, and they have a hook, eye or some other means of attachment at each end. o Compression springs are designed to become shorter when loaded. Their turns (loops) are not touching in the unloaded position, and they need no attachment points.
  8. 8. 8  Volute spring - a compression coil spring in the form of a cone so that under compression the coils are not forced against each other, thus permitting longer travel.  Hairspring or balance spring – a delicate spiral spring used in watches, galvanometers, and places where electricity must be carried to partially rotating devices such as steering wheels without hindering the rotation.  Leaf spring – a flat spring used in vehicle suspensions, electrical switches, and bows.  V-spring – used in antique firearm mechanisms such as the wheellock, flintlock and percussion cap locks. Also door-lock spring, as used in antique door latch mechanisms. Other types include :  Belleville washer or Belleville spring – a disc shaped spring commonly used to apply tension to a bolt (and also in the initiation mechanism of pressure-activated landmines).  Constant-force spring — a tightly rolled ribbon that exerts a nearly constant force as it is unrolled.  Gas spring – a volume of gas which is compressed.  Ideal Spring – the notional spring used in physics: it has no weight, mass, or damping losses. The force exerted by the spring is proportional to the distance the spring is stretched or compressed from its relaxed position.[8]  Mainspring – a spiral ribbon shaped spring used as a power store in clockwork mechanisms: watches, clocks, music boxes, windup toys, and mechanically powered flashlights  Negator spring – a thin metal band slightly concave in cross-section. When coiled it adopts a flat cross-section but when unrolled it returns to its former curve, thus producing a constant force throughout the displacement and negating any tendency to re-wind. The most common application is the retracting steel tape rule.[9]  Progressive rate coil springs – A coil spring with a variable rate, usually achieved by having unequal pitch so that as the spring is compressed one or more coils rests against its neighbour.  Rubber band – a tension spring where energy is stored by stretching the material.  Spring washer – used to apply a constant tensile force along the axis of a fastener.  Torsion spring – any spring designed to be twisted rather than compressed or extended. Used in torsion bar vehicle suspension systems.  Wave spring – the name applies to a multitude of wave shaped springs, washers and expanders, including linear springs, all of which are generally made with flat wire or discs which are marcelled according to industrial terms, usually by die-stamping, into a wavy regular pattern resulting in curvilinear lobes. Round wire wave springs exist as well. Types include : wave washer, single turn wave spring, multi-turn wave spring, linear wave spring, marcel expander, interlaced wave spring and nested wave spring amongst others.
  9. 9. 9 As long as they are not stretched or compressed beyond their elastic limit, most springs obey Hooke's law, which states that the force with which the spring pushes back is linearly proportional to the distance from its equilibrium length:F= -kx x is the displacement vector – the distance and direction the spring is deformed from its equilibrium length. F is the resulting force vector – the magnitude and direction of the restoring force the spring exerts k is the rate, spring constant or force constant of the spring, a constant that depends on the spring's material and construction. The negative sign indicates that the force the spring exerts is in the opposite direction from its displacement Coil springs and other common springs typically obey Hooke's law. There are useful springs that don't: springs based on beam bending can for example produce forces that vary nonlinearly with displacement. If made with constant pitch (wire thickness), conical springs will have a variable rate. However, a conical spring can be made to have a constant rate by creating the spring with a variable pitch. A larger pitch in the larger-diameter coils and a smaller pitch in the smaller-diameter coils will force the spring to collapse or extend all the coils at the same rate when deformed. In classical physics, a spring can be seen as a device that stores potential energy, specifically elastic potential energy, by straining the bonds between the atoms of an elastic material. Hooke's law of elasticity states that the extension of an elastic rod (its distended length minus its relaxed length) is linearly proportional to its tension, the force used to stretch it. Similarly, the contraction (negative extension) is proportional to the compression (negative tension). This law actually holds only approximately, and only when the deformation (extension or contraction) is small compared to the rod's overall length. Fig.-D
  10. 10. 2.4BEARING: A bearing is a machine element reduces friction between moving parts free linear movement of the mov prevent a motion by controlling the bearings facilitate the desired motion by minimizing according to the type of operation, the motions allowed, or to the directions of the loads (forces) applied to the parts. Rotary bearings hold rotating components such as transfer axial and radial loads from the source of the load to the structure simplest form of bearing, the plain bearing often used to reduce friction. In the rolling elements such as rollers or balls with a circular cross races or journals of the bearing assembly. A wide variety of bearing designs exists to allow the demands of the application to be correctly met for m and performance. The term "bearing" is derived from the verb " allows one part to bear (i.e., to support) another. The simplest bearings are or formed into a part, with varying degrees of control over the form, size, of the surface. Other bearings are separate devices installed into a machine or machine part. The most sophisticated bearings for the most demanding a manufacture requires some of the highest standards of By far, the most common bearing is the contact, often with a lubricant such as oil or graphite. A plain bearing may or may not be a discrete device. It may be nothing more than the through it, or of a planar surface that may be a layer of bearing metal separable sleeve (discrete). With suitab acceptable accuracy, life, and friction at minimal cost. Therefore, they are very widely used. 10 machine element that constrains relative motion to only the desired motion, and moving parts. The design of the bearing may, for example, provide for movement of the moving part or for free rotation around a fixed axis prevent a motion by controlling the vectors of normal forces that bear on the moving parts. Most bearings facilitate the desired motion by minimizing friction. Bearings are classified broadly according to the type of operation, the motions allowed, or to the directions of the loads (forces) Rotary bearings hold rotating components such as shafts or axles within mechanical systems, and transfer axial and radial loads from the source of the load to the structure supporting it. The plain bearing, consists of a shaft rotating in a hole. often used to reduce friction. In the ball bearing and roller bearing, to prevent sliding rolling elements such as rollers or balls with a circular cross-section are located between the races or journals of the bearing assembly. A wide variety of bearing designs exists to allow the demands of the application to be correctly met for maximum efficiency, reliability, durability The term "bearing" is derived from the verb "to bear" a bearing being a machine element that ., to support) another. The simplest bearings are bearing surfaces or formed into a part, with varying degrees of control over the form, size, roughness of the surface. Other bearings are separate devices installed into a machine or machine part. The most sophisticated bearings for the most demanding applications are very precise manufacture requires some of the highest standards of current technology. By far, the most common bearing is the plain bearing, a bearing which uses surfaces in rubbing such as oil or graphite. A plain bearing may or may not be a device. It may be nothing more than the bearing surface of a hole with a shaft passing through it, or of a planar surface that bears another (in these cases, not a discrete device); or it bearing metal either fused to the substrate (semi-discrete) or in the form of a separable sleeve (discrete). With suitable lubrication, plain bearings often give entirely acceptable accuracy, life, and friction at minimal cost. Therefore, they are very widely used. Fig.-E that constrains relative motion to only the desired motion, and . The design of the bearing may, for example, provide for rotation around a fixed axis; or, it may that bear on the moving parts. Most friction. Bearings are classified broadly according to the type of operation, the motions allowed, or to the directions of the loads (forces) within mechanical systems, and supporting it. The , consists of a shaft rotating in a hole. Lubrication is , to prevent sliding friction, section are located between the races or journals of the bearing assembly. A wide variety of bearing designs exists to allow the aximum efficiency, reliability, durability " a bearing being a machine element that bearing surfaces, cut roughness and location of the surface. Other bearings are separate devices installed into a machine or machine part. The precise devices; their , a bearing which uses surfaces in rubbing such as oil or graphite. A plain bearing may or may not be a of a hole with a shaft passing s, not a discrete device); or it discrete) or in the form of a le lubrication, plain bearings often give entirely acceptable accuracy, life, and friction at minimal cost. Therefore, they are very widely used.
  11. 11. 11 TYPES There are at least 6 common types of bearing, each of which operates on different principles:  Plain bearing, consisting of a shaft rotating in a hole. There are several specific styles: bushing, journal bearing, sleeve bearing, rifle bearing, composite bearing.  Rolling-element bearing, in which rolling elements placed between the turning and stationary races prevent sliding friction. There are two main types o Ball bearing, in which the rolling elements are spherical balls o Roller bearing, in which the rolling elements are cylindrical rollers  Jewel bearing, a plain bearing in which one of the bearing surfaces is made of an ultrahard glassy jewel material such as sapphire to reduce friction and wear  Fluid bearing, a noncontact bearing in which the load is supported by a gas or liquid,  Magnetic bearing, in which the load is supported by a magnetic field  Flexure bearing, in which the motion is supported by a load element which bends. Motions Common motions permitted by bearings are:  axial rotation e.g. shaft rotation  linear motion e.g. drawer  spherical rotation e.g. ball and socket joint  hinge motion e.g. door, elbow, knee Friction Reducing friction in bearings is often important for efficiency, to reduce wear and to facilitate extended use at high speeds and to avoid overheating and premature failure of the bearing. Essentially, a bearing can reduce friction by virtue of its shape, by its material, or by introducing and containing a fluid between surfaces or by separating the surfaces with an electromagnetic field.  By shape, gains advantage usually by using spheres or rollers, or by forming flexure bearings.  By material, exploits the nature of the bearing material used. (An example would be using plastics that have low surface friction.)  By fluid, exploits the low viscosity of a layer of fluid, such as a lubricant or as a pressurized medium to keep the two solid parts from touching, or by reducing the normal force between them.  By fields, exploits electromagnetic fields, such as magnetic fields, to keep solid parts from touching.  Air pressure exploits air pressure to keep solid parts from touching.
  12. 12. 12 Combinations of these can even be employed within the same bearing. An example of this is where the cage is made of plastic, and it separates the rollers/balls, which reduce friction by their shape and finish. Loads Bearing design varies depending on the size and directions of the forces that they are required to support. Forces can be predominately radial, axial (thrust bearings), or bending moments perpendicular to the main axis. Stiffness A second source of motion is elasticity in the bearing itself. For example, the balls in a ball bearing are like stiff rubber, and under load deform from round to a slightly flattened shape. The race is also elastic and develops a slight dent where the ball presses on it. The stiffness of a bearing is how the distance between the parts which are separated by the bearing varies with applied load. With rolling element bearings this is due to the strain of the ball and race. With fluid bearings it is due to how the pressure of the fluid varies with the gap (when correctly loaded, fluid bearings are typically stiffer than rolling element bearings). Speeds Different bearing types have different operating speed limits. Speed is typically specified as maximum relative surface speeds, often specified ft/s or m/s. Rotational bearings typically describe performance in terms of the product DN where D is the mean diameter (often in mm) of the bearing and N is the rotation rate in revolutions per minute. Generally there is considerable speed range overlap between bearing types. Plain bearings typically handle only lower speeds, rolling element bearings are faster, followed by fluid bearings and finally magnetic bearings which are limited ultimately by centripetal force overcoming material strength Maintenance and lubrication Many bearings require periodic maintenance to prevent premature failure, but many others require little maintenance. The latter include various kinds of fluid and magnetic bearings, as well as rolling-element bearings that are described with terms including sealed bearing and sealed for life. These contain seals to keep the dirt out and the grease in. They work successfully in many applications, providing maintenance-free operation. Some applications cannot use them effectively. Nonsealed bearings often have a grease fitting, for periodic lubrication with a grease gun, or an oil cup for periodic filling with oil.
  13. 13. 2.5GEAR: A gear or cogwheel is a rotating toothed part to transmit torque. Gea power source. Gears almost always produce a change in torque, creating a through their gear ratio, and thus may be considered a meshing gears all have the same shape. Two or more meshing gears, working in a sequence, are called a gear train or a transmission thereby producing translation instead of rotation. The gears in a transmission are analogous to the wheels in a crossed, belt advantage of gears is that the teeth When two gears mesh, if one gear is bigger than the other, a mechanical advantage is produced, with the rotational speeds, and the torques, of th diameters. In transmissions with multiple gear ratios "gear" as in "first gear" refers to a gear ratio rather than an actual physical gear. The term describes similar devices, even when the gear ratio is the device does not actually contain gears, as in a Types: Internal gear An external gear is one with the teeth formed on the outer surface of a cylinder or cone. Conversely, an internal gear is one with the teeth formed on the inner surface of a cylinder or cone. For bevel gears, an internal gear is one with the gears do not cause output shaft direction reversal Spur Gear : 13 machine part having cut teeth, or cogs, which mesh with another . Geared devices can change the speed, torque, and direction of a . Gears almost always produce a change in torque, creating a mechanical advantage , and thus may be considered a simple machine. The teeth on the two meshing gears all have the same shape. Two or more meshing gears, working in a sequence, are transmission. A gear can mesh with a linear toothed part, called a rack, instead of rotation. The gears in a transmission are analogous to the wheels in a crossed, belt pulley advantage of gears is that the teeth of a gear prevent slippage. When two gears mesh, if one gear is bigger than the other, a mechanical advantage is produced, , and the torques, of the two gears differing in proportion to their In transmissions with multiple gear ratios—such as bicycles, motorcycles, and cars "gear" as in "first gear" refers to a gear ratio rather than an actual physical gear. The term describes similar devices, even when the gear ratio is continuous rather than discrete the device does not actually contain gears, as in a continuously variable transmission Fig.-F An external gear is one with the teeth formed on the outer surface of a cylinder or cone. Conversely, an internal gear is one with the teeth formed on the inner surface of a cylinder or , an internal gear is one with the pitch angle exceeding 90 degrees. Internal gears do not cause output shaft direction reversal. Fig.-G part having cut teeth, or cogs, which mesh with another red devices can change the speed, torque, and direction of a mechanical advantage, . The teeth on the two meshing gears all have the same shape. Two or more meshing gears, working in a sequence, are . A gear can mesh with a linear toothed part, called a rack, pulley system. An When two gears mesh, if one gear is bigger than the other, a mechanical advantage is produced, e two gears differing in proportion to their such as bicycles, motorcycles, and cars—the term "gear" as in "first gear" refers to a gear ratio rather than an actual physical gear. The term discrete, or when continuously variable transmission. An external gear is one with the teeth formed on the outer surface of a cylinder or cone. Conversely, an internal gear is one with the teeth formed on the inner surface of a cylinder or angle exceeding 90 degrees. Internal
  14. 14. Spur gears or straight-cut gears are the simplest type of gear. They consist of a cylinder or disk with teeth projecting radially. Though the teeth are not straight to achieve a constant drive ratio, mainly tooth is straight and aligned parallel to the axis of r only if fitted to parallel shafts. excellent at moderate speeds but tend to be noisy at high speeds. Helical: Helical or "dry fixed" gears offer a refinement over spur gears. The leading edges of the teeth are not parallel to the axis of rotation, but are set at an angle. Since the gear is curved, this angling makes the tooth shape a segment of a orientations. The former refers to when the shafts are parallel to each other; this is the most common orientation. In the latter, the shafts are non are sometimes known as "skew gears". The angled teeth engage more gradually than do spur gear teeth, causing them to run more smoothly and quietly. With parallel helical gears, each pair of teeth first make contact point at one side of the gear wheel; a moving curve of contact then grows gradually across the tooth face to a maximum, then recedes until the teeth break contact at a single point on the opposite side. In spur gears, teeth suddenly meet at a causing stress and noise. Spur gears make a characteristic whine at high speeds. For this reason spur gears are used in low-speed applications and in situations where noise control is not a problem, and helical gears are used in high where noise abatement is important. A disadvantage of helical gears is a resultant accommodated by appropriate thrust bearings the meshing teeth, often addressed with additives in the lubricant. 14 cut gears are the simplest type of gear. They consist of a cylinder or disk with teeth projecting radially. Though the teeth are not straight-sided (but usually of special form to achieve a constant drive ratio, mainly involute but less commonly cycloidal), the edge of each tooth is straight and aligned parallel to the axis of rotation. These gears mesh together correctly No axial thrust is created by the tooth loads. Spur gears are excellent at moderate speeds but tend to be noisy at high speeds. Fig.-H Helical or "dry fixed" gears offer a refinement over spur gears. The leading edges of the teeth are not parallel to the axis of rotation, but are set at an angle. Since the gear is curved, this angling makes the tooth shape a segment of a helix. Helical gears can be meshed in parallel or crossed orientations. The former refers to when the shafts are parallel to each other; this is the most common orientation. In the latter, the shafts are non-parallel, and in this configuration the gears are sometimes known as "skew gears". The angled teeth engage more gradually than do spur gear teeth, causing them to run more smoothly and quietly. With parallel helical gears, each pair of teeth first make contact point at one side of the gear wheel; a moving curve of contact then grows gradually across the tooth face to a maximum, then recedes until the teeth break contact at a single point on the opposite side. In spur gears, teeth suddenly meet at a line contact across their entire width, causing stress and noise. Spur gears make a characteristic whine at high speeds. For this reason speed applications and in situations where noise control is not a are used in high-speed applications, large power transmission, or is important. A disadvantage of helical gears is a resultant thrust along the axis of the gear, which must be thrust bearings, and a greater degree of sliding friction the meshing teeth, often addressed with additives in the lubricant. cut gears are the simplest type of gear. They consist of a cylinder or disk sided (but usually of special form ), the edge of each otation. These gears mesh together correctly No axial thrust is created by the tooth loads. Spur gears are Helical or "dry fixed" gears offer a refinement over spur gears. The leading edges of the teeth are not parallel to the axis of rotation, but are set at an angle. Since the gear is curved, this angling . Helical gears can be meshed in parallel or crossed orientations. The former refers to when the shafts are parallel to each other; this is the most llel, and in this configuration the gears The angled teeth engage more gradually than do spur gear teeth, causing them to run more smoothly and quietly. With parallel helical gears, each pair of teeth first make contact at a single point at one side of the gear wheel; a moving curve of contact then grows gradually across the tooth face to a maximum, then recedes until the teeth break contact at a single point on the line contact across their entire width, causing stress and noise. Spur gears make a characteristic whine at high speeds. For this reason speed applications and in situations where noise control is not a speed applications, large power transmission, or along the axis of the gear, which must be sliding friction between
  15. 15. 15 Bevel: Fig.-I A bevel gear is shaped like a right circular cone with most of its tip cut off. When two bevel gears mesh, their imaginary vertices must occupy the same point. Their shaft axes also intersect at this point, forming an arbitrary non-straight angle between the shafts. The angle between the shafts can be anything except zero or 180 degrees. Bevel gears with equal numbers of teeth and shaft axes at 90 degrees are called miter gears. Hypoid: Fig.-J Hypoid gears resemble spiral bevel gears except the shaft axes do not intersect. The pitch surfaces appear conical but, to compensate for the offset shaft, are in fact hyperboloids of revolution. Hypoid gears are almost always designed to operate with shafts at 90 degrees. Depending on which side the shaft is offset to, relative to the angling of the teeth, contact between hypoid gear teeth may be even smoother and more gradual than with spiral bevel gear teeth, but also have a sliding action along the meshing teeth as it rotates and therefore usually require some of the most viscous types of gear oil to avoid it being extruded from the mating tooth faces, the oil is normally designated HP (for hypoid) followed by a number denoting the
  16. 16. 16 viscosity. Also, the pinion can be designed with fewer teeth than a spiral bevel pinion, with the result that gear ratios of 60:1 and higher are feasible using a single set of hypoid gears.This style of gear is most common in motor vehicle drive trains, in concert with a differential. Whereas a regular (nonhypoid) ring-and-pinion gear set is suitable for many applications, it is not ideal for vehicle drive trains because it generates more noise and vibration than a hypoid does. Worm gear: Fig.-K Worm-and-gear sets are a simple and compact way to achieve a high torque, low speed gear ratio. For example, helical gears are normally limited to gear ratios of less than 10:1 while worm- and-gear sets vary from 10:1 to 500:1. A disadvantage is the potential for considerable sliding action, leading to low efficiency. A worm gear is a species of helical gear, but its helix angle is usually somewhat large (close to 90 degrees) and its body is usually fairly long in the axial direction. These attributes give it screw like qualities. The distinction between a worm and a helical gear is that at least one tooth persists for a full rotation around the helix. If this occurs, it is a 'worm'; if not, it is a 'helical gear'. A worm may have as few as one tooth. If that tooth persists for several turns around the helix, the worm appears, superficially, to have more than one tooth, but what one in fact sees is the same tooth reappearing at intervals along the length of the worm. The usual screw nomenclature applies: a one-toothed worm is called single thread or single start; a worm with more than one tooth is called multiple thread or multiple start. The helix angle of a worm is not usually specified. Instead, the lead angle, which is equal to 90 degrees minus the helix angle, is given. In a worm-and-gear set, the worm can always drive the gear. However, if the gear attempts to drive the worm, it may or may not succeed. Particularly if the lead angle is small, the gear's teeth may simply lock against the worm's teeth, because the force component circumferential to the worm is not sufficient to overcome friction. Worm-and-gear sets that do lock are called self locking, which can be used to advantage, as for instance when it is desired to set the position of a mechanism by turning the worm and then have the mechanism hold that position. An example is the machine head found on some types of stringed instruments.If the gear in a worm-and-gear set is an ordinary helical gear only a single point of contact is achieved. If medium to high power transmission is desired, the tooth shape of
  17. 17. the gear is modified to achieve more intimate contact by maki each other. This is done by making both concave and joining them at a a cone-drive or "Double enveloping". Rack and Pinion: A rack is a toothed bar or rod that can be thought of as a sector gear with an infinitely large radius of curvature. Torque can be converted to linear force by meshing a rack with a pinion: the pinion turns; the rack moves in a straight line. Such a mechan convert the rotation of the steering feature in the theory of gear geometry, where, for instance, the tooth shape of an interchangeable set of gears may be specified for the rack, (infinite radius), and the tooth shapes for ge particular actual radii are then derived from that. The rack and pinion gear type is employed in a rack railway. For example, in a rack railway a railcar engages a rack between the rails and forces a Gear materials: Numerous nonferrous alloys, cast irons, powder manufacture of gears. However, steels are most commonly used because of their high strength to-weight ratio and low cost. Plastic is commonly used where cost or weight is a concern. A properly designed plastic gear can replace steel in many cases because it has many desirable properties, including dirt tolerance, low speed meshing, the ability to "skip" quite well ability to be made with materials that don't need additional lubricati plastic gears to reduce costs in consumer items including copy machines, optical storage devices, cheap dynamos, consumer audio equipment, servo motors, and printers. Another a the use of plastics was the reduction o severe jamming (as of the paper in a printer), the plastic gear teeth would be torn free of their substrate, allowing the drive mechanism to then spin freely (instead of damaging itself by 17 the gear is modified to achieve more intimate contact by making both gears partially envelop each other. This is done by making both concave and joining them at a saddle point or "Double enveloping". Fig.-L A rack is a toothed bar or rod that can be thought of as a sector gear with an infinitely large radius of curvature. Torque can be converted to linear force by meshing a rack with a pinion: the pinion turns; the rack moves in a straight line. Such a mechanism is used in automobiles to steering wheel into the left-to-right motion of the tie rod(s). Racks also feature in the theory of gear geometry, where, for instance, the tooth shape of an interchangeable set of gears may be specified for the rack, (infinite radius), and the tooth shapes for ge particular actual radii are then derived from that. The rack and pinion gear type is employed in a rack railway, the rotation of a pinion mounted on a between the rails and forces a train up a steep slope. alloys, cast irons, powder-metallurgy and plastics are used in the manufacture of gears. However, steels are most commonly used because of their high strength weight ratio and low cost. Plastic is commonly used where cost or weight is a concern. A rly designed plastic gear can replace steel in many cases because it has many desirable properties, including dirt tolerance, low speed meshing, the ability to "skip" quite well ability to be made with materials that don't need additional lubrication. Manufacturers have used plastic gears to reduce costs in consumer items including copy machines, optical storage devices, cheap dynamos, consumer audio equipment, servo motors, and printers. Another a was the reduction of repair costs for certain expensive machines. In cases of severe jamming (as of the paper in a printer), the plastic gear teeth would be torn free of their substrate, allowing the drive mechanism to then spin freely (instead of damaging itself by ng both gears partially envelop saddle point; this is called A rack is a toothed bar or rod that can be thought of as a sector gear with an infinitely large radius of curvature. Torque can be converted to linear force by meshing a rack with a pinion: the ism is used in automobiles to right motion of the tie rod(s). Racks also feature in the theory of gear geometry, where, for instance, the tooth shape of an interchangeable set of gears may be specified for the rack, (infinite radius), and the tooth shapes for gears of particular actual radii are then derived from that. The rack and pinion gear type is employed in a , the rotation of a pinion mounted on a locomotive or metallurgy and plastics are used in the manufacture of gears. However, steels are most commonly used because of their high strength- weight ratio and low cost. Plastic is commonly used where cost or weight is a concern. A rly designed plastic gear can replace steel in many cases because it has many desirable properties, including dirt tolerance, low speed meshing, the ability to "skip" quite well and the on. Manufacturers have used plastic gears to reduce costs in consumer items including copy machines, optical storage devices, cheap dynamos, consumer audio equipment, servo motors, and printers. Another advantage of f repair costs for certain expensive machines. In cases of severe jamming (as of the paper in a printer), the plastic gear teeth would be torn free of their substrate, allowing the drive mechanism to then spin freely (instead of damaging itself by
  18. 18. straining against the jam). This use of "sacrificial" gear teeth avoided destroying the much more expensive motor and related parts. This method has been superseded, in more recent designs, by the use of clutches and torque- or current NOMENCLATURE The figure given below shows the various technical terms used in manufacturing a gear and determines the output of the same. 2.6LED LIGHT: A light-emitting diode (LED) is a two which emits light when activated. When a suitable able to recombine with electron holes This effect is called electroluminescence of the photon) is determined by the energy small (less than 1 mm2 ) and integrated optical components may be used to shape the pattern. Appearing as practical electronic components in 1962, infrared light. Infrared LEDs are still frequently used as transmitting elements in remote circuits, such as those in remote controls for a wide variety of consumer electronics. The first 18 g against the jam). This use of "sacrificial" gear teeth avoided destroying the much more expensive motor and related parts. This method has been superseded, in more recent designs, by or current-limited motors. figure given below shows the various technical terms used in manufacturing a gear and determines the output of the same. Fig.-M emitting diode (LED) is a two-lead semiconductor light source. It is a p– which emits light when activated. When a suitable voltage is applied to the leads, electron holes within the device, releasing energy in the form of electroluminescence, and the color of the light (corresponding to the energy of the photon) is determined by the energy band gap of the semiconductor. LEDs are typically ) and integrated optical components may be used to shape the Appearing as practical electronic components in 1962, the earliest LEDs emitted low infrared light. Infrared LEDs are still frequently used as transmitting elements in remote circuits, such as those in remote controls for a wide variety of consumer electronics. The first g against the jam). This use of "sacrificial" gear teeth avoided destroying the much more expensive motor and related parts. This method has been superseded, in more recent designs, by figure given below shows the various technical terms used in manufacturing a gear and –n junction diode, is applied to the leads, electrons are within the device, releasing energy in the form of photons. , and the color of the light (corresponding to the energy of the semiconductor. LEDs are typically ) and integrated optical components may be used to shape the radiation the earliest LEDs emitted low-intensity infrared light. Infrared LEDs are still frequently used as transmitting elements in remote-control circuits, such as those in remote controls for a wide variety of consumer electronics. The first
  19. 19. 19 visible-light LEDs were also of low intensity and limited to red. Modern LEDs are available across the visible, ultraviolet, and infrared wavelengths, with very high brightness. Early LEDs were often used as indicator lamps for electronic devices, replacing small incandescent bulbs. They were soon packaged into numeric readouts in the form of seven- segment displays and were commonly seen in digital clocks. Recent developments in LEDs permit them to be used in environmental and task lighting. LEDs have allowed new displays and sensors to be developed, while their high switching rates are also used in advanced communications technology. LEDs have many advantages over incandescent light sources including lower energy consumption, longer lifetime, improved physical robustness, smaller size, and faster switching. Light-emitting diodes are now used in applications as diverse as aviation lighting, automotive headlamps, advertising, general lighting, traffic signals, camera flashes, and lighted wallpaper. As of 2017, LED lights home room lighting are as cheap or cheaper than compact fluorescent lamp sources of comparable output. They are also significantly more energy efficient and, arguably, have fewer environmental concerns linked to their disposal. Working principle The inner workings of an LED, showing circuit (top) and band diagram (bottom) A P-N junction can convert absorbed light energy into a proportional electric current. The same process is reversed here (i.e. the P-N junction emits light when electrical energy is applied to it). This phenomenon is generally called electroluminescence, which can be defined as the emission of light from a semi-conductor under the influence of an electric field. The charge carriers recombine in a forward-biased P-N junction as the electrons cross from the N-region and recombine with the holes existing in the P-region. Free electrons are in the conduction band of energy levels, while holes are in the valence energy band. Thus the energy level of the holes will be lesser than the energy levels of the electrons. Some portion of the energy must be dissipated in order to recombine the electrons and the holes. This energy is emitted in the form of heat and light. The electrons dissipate energy in the form of heat for silicon and germanium diodes but in gallium arsenide phosphide (GaAsP) and gallium phosphide (GaP) semiconductors, the electrons dissipate energy by emitting photons. Fig.-N
  20. 20. 20 2.7Pulley: A pulley is a wheel on an axle or shaft that is designed to support movement and change of direction of a taut cable, supporting shell is referred to as a "block." A pulley may also be called a sheave or drum and may have a groove or grooves between two flanges around its circumference. The drive element of a pulley system can be a rope, cable, belt, or chain that runs over the pulley inside the groove or grooves. Hero of Alexandria identified the pulley as one of six simple machines used to lift weights.[1] Pulleys are assembled to form a block and tackle in order to provide mechanical advantage to apply large forces. Pulleys are also assembled as part of belt and chain drives in order to transmit power from one rotating shaft to another. Fig.-O 2.8BELT: A belt is a loop of flexible material used to link two or more rotating shafts mechanically, most often parallel. Belts may be used as a source of motion, to transmit power efficiently, or to track relative movement. Fig.-P
  21. 21. 21 Belts are looped over pulleys and may have a twist between the pulleys, and the shafts need not be parallel. In a two pulley system, the belt can either drive the pulleys normally in one direction (the same if on parallel shafts), or the belt may be crossed, so that the direction of the driven shaft is reversed (the opposite direction to the driver if on parallel shafts). As a source of motion, a conveyor belt is one application where the belt is adapted to carry a load continuously between two points. 2.9Dynamo: A dynamo is an electrical generator that produces direct current with the use of a commutator. Dynamos were the first electrical generators capable of delivering power for industry, and the foundation upon which many other later electric-power conversion devices were based, including the electric motor, the alternating-current alternator, and the rotary converter. Today, the simpler alternator dominates large scale power generation, for efficiency, reliability and cost reasons. A dynamo has the disadvantages of a mechanical commutator. Also, converting alternating to direct current using power rectification devices (vacuum tube or more recently solid state) is effective and usually economical. Fig.-Q 2.10Diode: A semiconductor device with two terminals, typically allowing the flow of current in one direction only. In electronics, a diode is a two-terminal electronic component that conducts primarily in one direction it has low resistance to the current in one direction, and high (ideally infinite) resistance in the other. A semiconductor diode, the most common type today, is a crystalline piece of semiconductor material with a p–n junction connected to two electrical terminals. A vacuum tube diode has two electrodes, a plate and a heated cathode. Semiconductor diodes were the first semiconductor electronic devices.
  22. 22. 22 CHAPTER-3 WORKING Working Of Foot Step Power Generation: The complete diagram of the power generation using FOOT STEP is given below. L-shapes window s used to generate the power. The pushing power is converted into electrical energy by proper driving arrangement. The rack & pinion, spring arrangement is fixed at the FOOT STEP which is mounded below the L-shapes window. The spring is used to return the inclined Lshapes window in same position by releasing the load. The pinion shaft is connected to the supporter by end bearings as shown. The larger sprocket also coupled with the pinion shaft, so that I is running the same speed of pinion. This larger pulley is used to transfer the rotation force to the smaller sprocket. The smaller sprocket is running same direction for the forward an reverse direction of rotational movement of the larger sprocket. This action locks like a cycle pedaling action. The fly wheel and gear wheel is also coupled to the smaller sprocket shaft. The flywheel is used to increase the rpm of the smaller sprocket shaft. The gear wheel is coupled to the generator shaft with the help of another gear wheel. The generator is used here, is permanent magnet D.C generator. The generated voltage is 12Volt D.C. This D.C voltage is stored to the Lead-acid 12 Volt battery. The battery is connected to the inverter. This inverter is used to convert the 12 Volt D.C to the 230 Volt A.C. This working principle is already explained the above chapter. This 230 Volt A.C voltage is used to activate the light, fan and etc. By increasing the capacity of battery and inverter circuit, the power rating is increased. This arrangement is fitted in FOOT STEPs; the complete arrangement is kept inside the floor level except the pushing arrangement. Fig.-R
  23. 23. 23 CHAPTER -4 CALCULATIONS SPECIFICATION OF PINION:  Material : Mild Steel  Outside diameter : 38mm  Circular pitch : 4.7mm  Tooth depth : 3.375mm  Module : 2.1mm  Pressure angle : 21 degree  Pitch circle diameter : 37mm  Addendum : 1mm  Dedendum : 1.2mm  Circular tooth Thickness : 2.355mm  Fillet radius : 0.45mm  Clearance : 0.375mm  No. of teeth1: 16 DESIGN OF RACK:  Pitch circle diameter of the gear is = 37mm  Circumference of the gear is = 3.14x pitch circle diameter= 116.8mm  The dimension is for 360 degree rotations  For 180 degree rotations the rack length is 58.4 mm SPECIFICATION OF RACK:  Material : Mild Steel  Module : 1.5mm  Cross-section :155x12.5mm  Teeth on the rack is adjusted = 18
  24. 24. 24 OUTPUT POWER CALCULATION: Let us consider,The mass of a body = 60 Kg (Approximately) Height of speed brake = 7.5cm ∴Work done = Force x Distance Here, Force = Weight of the Body = 60 Kg x 9.81 = 588.6 N Distance traveled by the body = Height of the speed brak= 7.5cm= 0.075 m ∴Output power = Work done/Sec = (588.6 x 0.075)/60 = 0.7375Watts(For One pushing force) Material of spring: Steel Stiffness of spring: 20 Diameter of pulley= 12.5cm Width of pulley= 1.25cm Dynamo output= 12volt, 2amp Diameter of shaft= 2.5cm Length of shaft= 19 inch Length of step = 18.1 inch Breath of step= 10.9inch Height of step= 4.5inch Thickness of frame= 1 inch Weight of whole body= 20kg(approx.) Battery capacity= 12volt
  25. 25. 25 CHAPTER :- 5 RESULT  Power generated by the system = .7375 watts  Voltage = 12 volt  Current = 2 amperes
  26. 26. 26 CHAPTER-6 APPLICATIONS ADVANTAGES:  Power generation is simply walking on the step.  Power also generated by running or exercising on the step.  No need fuel input.  This is a Non-conventional system.  Battery is used to store the generated power. DISADVANTAGES:  Only applicable for the particular place.  Mechanical moving parts are high.  Initial cost of this arrangement is high.  Care should be taken for batteries APPLICATIONS: Power generation using foot step can be used in most of the places such as  Colleges.  Schools.  Cinema theatres.  Shopping complex .  Many other buildings.
  27. 27. 27 CHAPTER-7 ACTUAL PROJECT PHOTO Fig.-S
  28. 28. 28 CHAPTER-8 CONCLUSION In concluding the words of our project, since the power generation using foot step get its energy requirements from the Non-renewable source of energy. There is no need of power from the mains and there is less pollution in this source of energy. It is very useful to the places all roads and as well as all kind of foot step which is used to generate the non conventional energy like electricity. It is able to extend this project by using same arrangement and construct in the foot steps/speed breaker so that increase the power production rate by fixing school and colleges, highways etc.
  29. 29. 29 CHAPTER:-9 REFRENCES  BHANDARI V.B. “DESIGN OF MACHINE ELEMENTS”- TATA MCGRAW HILL,2007  PANDYA AND SHAH “ELEMENTS OF MACHINES DESIGN ”,2000  MAITRA, HANDBOOK OF GEAR DESIGN,TATA MCGRAW HILL,1995  T.NEJAT VEZIROYGAL , ALTERNATIVE ENERGY SOURCES-III, HEMISPHERE PUBLISHING CO.  BARBARA KEILER, ENERGY ALTERNATIVES, LUSCENTR BOOKS.  PRABHU T.J. FUNDAMENTALS OF MACHINES DESIGN,2009  RAI. G.D. “NON CONVENTIONAL ENERGY SOURCES”, KHANNA PUBLISHERS, DELHI  www.wikipedia.com  www.facebook.com/solidworkscommunity  https://en.wikipedia.org/wiki/Ansys

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