Saturday, March 30, 2019
Designing an automated lawn mower
Designing an automated lawn lawn mowerChapter 1 entry to the takeBackground to the researchThe first lawn mower was contrivance in 1827 and patented in 1830 by Edwin Beard Budding, an engineer from Stroud, Gloucestershire, England.He got this judgement after seeing a machine in a stuff industry, they apply a snip cylinder (or bladed reel) mounted on a bench to trim cloth to eviscerate a silver-tongued finish after weaving. Budding realized that a mistakable image would enable the cutting of grass if the mechanism could be mounted in a wheeled frame to make the blades rotate close to the lawns surface. start-off lawn mower was all do of cast iron and featured a large rear gyre with a cutting cylinder (reel) in the front. Cast iron gear wheels transmitted power from the rear roller to the cutting cylinder. These machines were remarkably similar to modern mowers.By 2000, zombiic be well-nigh important things in the future, no matter if they atomic number 18 used to pl ow in industry or at our homes, mimic some of the human race capabilities, or used to access dangerous environments, launched to space, or simply used to play with. They be help to reduce human dependencies in performing a task and to reduce eon for production while maintaining arranged quality of production outputs. Robotic devices argon commonly used in manufacturing industries and for domesticated use as well.Modern houses normally tend with grass neediness to be maintained at a short height, is most substance abuser upset. Traditional lawn mowing is often a trouble, dangerous and beat consuming in cutting the grass. The task of manual lawn mowing stomach be replaced by self-winding lawn mower employ a automaton programmed to perform such task. A machine homogeneous lawn mower is determinationed and installed in this job. automatic pistol Lawn mower besides tidy sum act as an aid to homeowners who keep no long-acting perform corporally demanding tasks, such as the elderly or disabled. On the residential side, many elderly and disabled enjoy lawn maintenance, but are no longer able to enjoy the satisfaction of maintaining their own lawn delinquent to the physical demands of tralatitious lawn mowing equipment. These researches (automatic lawn mowers) are very elderly and disabled amicable with the simple. Automatic lawn mower also has the Perfect Balance Between Eco-friendly and Practicality.Robots are very expensive, not any people really want to profane costly robotic devices. Create a low cost inexpensive automatic lawn mower will allow house owners to maintain their lawn without spending more than(prenominal) time and money. An autonomous robot can mow the lawn of a prone specific field of study of the garden without any human supervision.Research trouble / Research questionHowever with the continuous development, several resources also make the arbitrary abuse. Oil coal resources are depleting shortages of energy and serious contamination.In the 20th century, energy crisis is any great bottleneck (or price rise) in the supply of energy resources to an economy. It usually refers to the shortage of oil and accessoryally to electrical energy or other natural resources. An energy crisis may be referred to as an oil crisis, petroleum crisis, energy shortage, electricity shortage or electricity crisis.The near future, the petroleum crisis already is a very big problem. Globality by way of disburden, they would increase the petroleum price, and debase their expense. Still got another country, refer sb. when hes down increase the petroleum price, and gain profit. Market failure is accomplishable when monopoly manipulation of markets occurs. A crisis can develop due to industrial actions like union organized strikes and government embargoes. The cause may be over-consumption, age infrastructure and sometimes bottlenecks at oil refineries and port facilities restrict discharge supply. That crisis involves the industry, bu loathsomenessess, carrying trade, until economic policy.In response to the petroleum crisis, the principles of green energy and sustainable living movements gain popularity. This has led to increa uglinessg interest in trade power/fuel research such as fuel cubicle technology, liquid nitrogen economy, hydrogen fuel, biodiesel, solar energy, geothermal energy, tidal energy, vagabond power, and wind energy, and fusion power.Rotary mowers can throw out junk with tremendous force is one of the most dangerous tools around the home. from each one course of instruction, approximately 80,000 people with injuries caused by power mowers were treated in fatality departments. More than 9,000 of the people hurt were younger than 18 years.Lawn mower injuries imply deep cuts, loss of fingers and toes, broken and dislocated bones, burns, and eye and other injuries. any(prenominal) injuries are very serious. twain users of mowers and those who are nearby can be hurt.More than 20 percent of lawn mower injuries involving the hands, fingers or wrist. Some time the users want to adjust the height of the mowers wheels, forget pull out the stir up plug after that the lawn mower suddenly turns on. When the user use lawn mower also need to make sure all debris (rocks, sticks and toys) are removed from the yard before you begin mowing. Loose objects can project out of the lawn mower and cause serious injury.Aims and objectivesIn the course of design and installation of an autonomous robot, the following criteria are set to fulfill its objectivesThe robot must cutting grass in the surface areaThe robot must not be too costly and be cheap to allThe lawn mower cutting tool can be adaptable with servo motorThe robot also can be rechargeable energy with solar planer.To support an automated lawn mower which follows a programmed course of data point without the use of calibration marker, lights, wires, or buried conductorsTo provide an automated lawn mower tha t is versatile in programming such that it can be maneuvered to follow any physically possible path including ford over itself and reversal of directionJustification for the researchOn the residential side, many elderly and disabled enjoy lawn maintenance, but are no longer able to enjoy the satisfaction of maintaining their own lawn due to the physical demands of traditional lawn mowing equipment. These researches (automatic lawn mowers) are very elderly and disabled friendly with the simple.methodological analysis automatise lawn mower, are mower automatically along the edge of a swath which has been cut within or around an area of jolty grass. That includes a sensor assembly mounted on the front of the mower to detect the edge of the swath by sensing the different in height between uncut grass and the cut grass in the swath. In front of the lawn mower, also got a one touch sensor, that operator it will be automatic avoid collision with obstacles along its pathway. Automated la wn mower also can adjustable the cutting tool most 1cm3cm, this function is let the user choose which height with the grass. This mower using the solar planer to generate the power, and rechargeable lithium battery, let the mower moving more time.ConclusionAutomatic grass cutters are environmentally friendly (no petrol, oil or emissions). No need bagging and governing body of clippings is eliminated. It also can healthy and beautiful looking lawn. In addition to environmental protection, also can save user time and money.Chapter 2 Literature reviewMost people do not refer air pollution with mowing the lawn. Yet emissions from lawn mowers, snow blowers, chain saws, leaf vacuums, and similar outdoor power equipment are a significant source of pollution. Todays low-pitched engines give off high levels of carbon monoxide, a color little, odorless, poisonous gas. They also occur hydrocarbons and nitrogen oxides, pollutants that contribute to the formation of ozone. While ozone occ urs naturally in the revive atmosphere and shields the earth from harmful radiation, ozone at ground level is a noxious pollutant. Ground-level ozone impairs lung function, inhibits plant growth, and is a key ingredient of smog.Each weekend, close to 54 million Americans mow their lawns, using 800 million gallons of gas per year and producing tons of air pollutants. Garden equipment engines, which have had unregulated emissions until very recently, emit high levels of carbon monoxide, volatile organic compounds and nitrogen oxides, producing up to 5% of the nations air pollution and a good deal more in metropolitan areas. According to the U.S. Environmental Protection Agency (EPA), a traditional gas powered lawn mower produces as much air pollution as 43 new cars each is being fight offn 12,000 miles.Among assorted types of outdoor equipment, lawn mowers are an important contributor to community noise, with the blades contributing up to 50% of noise (Tauro Mann III, 1997). Law n mowers can be just as big as leaf blowers. According to the Canadian Hearing Society (1991), lawn mowers can emit 80-96 dB(A) when measured at a distance of three feet. handle gas-powered leaf blowers, gas-powered lawn mowers emit air pollutants. As portendd in Table 4 below, these air pollutants include hydrocarbons, carbon monoxide, nitrogen oxides and particulate matter.These emissions represent less than 5% of the total emissions of these individual pollutants in Canada, except for hydrocarbons, which are close to 14% of total hydrocarbon emissions (Environment Canada, 1994).Two-stroke lawn mowers tend to be more polluting than four-stroke models. For example, one study found that lawn mowers with two-stroke engines emit hydrocarbons at an average rate in excess of seven times the rate of emission from lawn mowers with four-stroke engines (Priest et al., 2000). Evaporative fuel emissions from lawn mowers are estimated to be 5.8 grams/day (Wong, 2001). Lawn mowers can be mo re polluting than driving a car. One half-hour of lawn mowing with a typical walk-behind mower produces as much hydrocarbon emissions as driving a 1995 automobile for about 100 miles or 160 kilometres (California Air Resources Board, 2000). A Swedish study found that the emissions produced from a lawn mower engine during one hour of operation were around 4000 g/h this is comparable to driving more than 150 km in a car with a three-way catalytic converter (Christensen Westerholm, 2001).Both lawn mower users and bystanders can be exposed to noise and air pollutant emissions. shapeures from Statistics Canada indicate that there were 5,850,000 lawn mowers in Canada in 1985, the majority of which were gas-powered (73.3%). There were comparatively fewer electric (23.9%) and push mowers (2.8%) (Environment Canada, 1994). Most lawn mowers that are available in the Canadian marketplace are imported (Maillette, 2001). According to information obtained from Statistics Canada, 126 walk-behind lawn mowers were imported into Canada during 1996-1999. Figures on domestic production of lawn mowers are not available from Industry Canada (Maillette, 2001).Automatic lawn mower (e.g., lawn mowers) contribute to noise and air pollution that can adversely affect human health and the environment, minimize noise, exhaust and evaporative emissions from lawn/garden equipment and protect public health.Chapter 3 Concept development and evaluationclock BeltBelt driver are provides a convenient promoter for transferring power from one archeological site to another. Belt are frequently demand to reduce the higher rotative speed of electric motors to the lower values take by mechanical equipment. But in this project are contrary, because the cutting tools need a top speed to operate. Normally in industrial, are using two general type of tap driver, v-belt and timing belt (synchronous belt).Since the cost of v-belt is coitionly low, the power output of a v-belt system may be increased by operating several belts side by side. All belts in the drive should stretch at the same time rate in order to keep the load equally divided among them. When one of the belts breaks, the entire group must usually be replaced. The drive may be inclined at any angle with a tight side at either the top or bottom. Since belts can operate on relatively wasted engine blocks, large reduction of the speed in a single drive are possible.EycUCTIUC4F1012MEFinal family ProjNew folderScreenHunter_08 Feb. 12 22.14.gifEycUCTIUC4F1012MEFinal Year ProjNew folderScreenHunter_06 Feb. 12 21.53.gifPitch diameter of a pulley P = No teeth on pulley x put down distance d =Belt contact angle = arc sin C = centre distanceBelt fall space fl = receive length small pulley CL2 =Contact length big pulley CL1 =Belt length L = 2(fl) + CL1+ CL2Total number of teeth on belt = large-mouthed pulley, P1 = No teeth on pulley x= 38 x= 61.4465mmSmall pulley, P2 = No teeth on pulley x= 18 x= 29.1063mmDrop distance, d === 16.1701mmBelt contact angle, = arc sin C = centre distance= arc sin= 7.87Belt fall length , fl == 116.9815mmContact length small pulley, CL2 === 41.7221mmContact length big pulley, CL1 == 61.4465= 104.9601mmBelt length, L = 2(fl) + CL1+ CL2= 2(116.9815mm) + 104.9601mm + 41.7221mm= 380.6452mmEycUCTIUC4F1012MEFinal Year ProjNew folderScreenHunter_04 Feb. 12 21.49.gifUsing micromagic system software project the belt length.EycUCTIUC4F1012MEFinal Year ProjNew folderScreenHunter_05 Feb. 12 21.53.gifImperial XL subsectionht = 1.27mmp = 5.08mmhs = 2.30mm sticker gearEycUCTIUC4F1012MEFinal Year ProjNew folderScreenHunter_01 Feb. 15 11.03.gifSpur Gear Formula14 degreePressure Angle20 and 25 degreePressure angleAddendum, aa =a =Dedendum, bb =b =Pitch diameter, DD =D =Outside diameter, DoDo =Do =Number of teeth, NN = D x PN = D x PTooth thickness, tt =t =Whole depth, htht =ht =Clearance, cc =c =Center distance, CC =C =Working depth, hkhk =hk =chordal tooth thickness, tctc = D sin ()t c = D sin ()Chordal addendum, acac = a +ac = a +Diametral pitch, PP =P =Center distance, CC =C = lummox and roller bearingsA ball bearing usually consists of four separate an inner ring, an outer ring, the balls and the cage or separator. To increase the contact area and permit larger loads to be carried, the ball run in curvilinear grooves in the rings. The spoke of the groove is slightly larger than the radius of the ball, and very slight amount of radial play must be provided. The bearing it thus permitted to adjust itself to small amounts of angular misalignment in the assembled shaft and mounting. The separator keeps the balls evenly space and prevents them from touching each in the sides, where their relative velocities are the greatest.Ball bearings are made in a extensive variety of type and size. Single row radial bearings are made in four series. Extra light, light, medium, and heavy, for each bore, as illustrated in Fig 1
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