Project Description ABSTRACT

Transcription

1 Prject Descriptin ABSTRACT Urban cncept vehicle is the final year capstne prject fr engineering department. This vehicle will be used as a shwcase at Nrthern Arizna University and has shwn its participatin fr Shell Ec-Marathn cmpetitin which was held annually in Hustn, Texas. The team s cntributin t the final vehicle was the final finished fairing and interir system which was implemented int the vehicle s chassis and suspensin systems. The fairing determines the attractin f the vehicle and cvers the chassis and cntrl systems. The interir design f vehicle was dne based n the ergnmics factrs prviding driver and passenger cmfrt and their ease f access t the cntrl systems. The vehicle was tested at the Shell Ec- Marathn cmpetitin fr the safety factrs and efficiency f the energy. INTRODUCTION The interir team is a part f five sub-grups f urban cncept vehicle. These sub-grups include chassis and suspensin, interir and fairing, drive train and mtr cntrl, steering and braking system, and electrical engineering team. The interir team s cntributin was t build the well finished fairing which is the bdy f the vehicle and interir cmpnents prviding driver interface. Tgether, the urban cncept vehicle team wrked t build an ec-friendly electric vehicle which represents the skills and knwledge f the students frm engineering department. This vehicle tk participatin fr Shell Ec-Marathn cmpetitin which was held n the end f March, 2012 at Hustn, Texas and passed all the technical inspectin t get int the track. The vehicle will be used as a shwcase at Nrthern Arizna University under the name f the client, Dr. Jhn Tester. PROBLEM STATEMENT Urban cncept vehicle prject was the client s gal t create a flagship prject which demnstrates the abilities and skills f the Engineering department. The vehicle was designed based n the requirements f client and Shell Ec-Marathn, manufactured, and tested by NAU Engineering senir students. The end result was an electric vehicle designed fr fuel efficiency with an urban design using electric mtrs as the energy surce t drive the vehicle and well finished interir including driver interface. The cmplete urban cncept vehicle was divided in five subgrups: chassis-suspensin, drive train, electrical, safety-braking-steering, and fairing-ergnmics. In additin t cmpleting their wn analysis, each subgrup integrated their designs with the cmplete car by wrking with every subgrup. This team s cntributin t the final vehicle was the design, manufacturing and implementatin f the vehicle s fairing and interir. The fairing was manufactured t cver the chassis and cntrl systems f vehicle and t prvide better aerdynamic perfrmance. Mrever, the fairing determines the lks and impressin f the vehicle. The interir design was dne based n the ergnmics factrs t prvide driver and passenger cmfrt and their ease f access t cntrl systems. This vehicle has enugh space fr tw peple (including driver and passenger) which als represent practical design fr driving in urban cities. The effectiveness f the vehicle

2 Prject Descriptin was tested at the Shell Ec-Marathn cmpetitin. The team fllwed a certain prcedure and had milestnes fr each phases. SHELL ECO-MARATHON The Shell Ec-Marathn Americas is an engineering cmpetitin held in dwntwn Hustn, Texas, in early April, and hsted by Shell Oil Crpratin. Started in 1939, it was a cmpetitin between scientists t create a vehicle with the highest mile per galln capability. The current frm f the cmpetitin is t encurage science and engineering students t explre new technlgical pssibilities. Multiple schls participate in the prttype and urban cncept divisins while aiming fr the highest fuel efficiency using gasline, diesel, hydrgen r electricity as energy surces. Shell hsts tw cmpetitins, the prttype and the urban cncept. The prttype cmpetitin fcuses n vehicles achieving the abslute maximum efficiencies pssible fr a vehicle that will transprt a persn n wheels with minimal size restrictins. The current verall recrd fr a prttype vehicle is held by the Plyjule team frm Plytech Nantes University f France with equivalent miles per galln f 11, using a fuel cell pwer surce. The urban cncept cmpetitin is a mre practical event, where vehicles are designed arund use within an urban setting. The vehicles must cmplete tw parking perids, where the vehicle cmes t a cmplete stp fr three secnds, during ten laps f the curse. At the finish, fficials measure the ttal fuel/energy used and rank the vehicles in a cmparable miles per galln value. The current verall recrd fr an urban cncept vehicle is 1, equivalent miles per galln using a fuel cell pwer surce frm the Hydr Cruisers team frm the De Haagse Hgeschl f the Netherlands. The current America s cmpetitin recrd is equivalent miles per galln by the Mater Dei High Schl s Supermileage team frm Evansville Indiana using an internal cmbustin engine. The UCV participated in the urban cncept divisin. Requirements and Specificatins Ec-Marathn Rules Dimensins The ttal vehicle height shuld be between 100 cm and 130 cm. The ttal bdy width is required t be within 120 cm and 130 cm. The ttal vehicle length must be between 220 cm and 350 cm. The driver s cmpartment must have a minimum height f 88 cm and a minimum width f 70cm at the driver s shulders. The vehicle weight shuld nt exceed 205 kg excluding the driver. Vehicle bdy The fairing/bdy shuld be cvering all mechanical parts excluding the wheels and suspensin whether the vehicle is viewed frm frnt, tp, rear r side views.

3 Prject Descriptin The wheels and suspensin must be fully cvered by the bdy when seen frm the tp view. Access t the vehicle by the driver must be as easy and practical as typically fund in prductin type passenger cars which have a specific dimensin requirement f minimum 500 x 800 mm and it is verified by rectangular template. The vehicle must have a rf cvering the driver s cmpartment. A windscreen with effective wiper(s) is required. Any access pening mechanisms (e.g. drs) must be firmly attached t the bdy f the vehicle by means f hinges, sliding rails, etc. Luggage space shuld be included with dimensin f 500 x 400 x 200 mm (L x H x W). Sharp edges, pints shuld be avided s that it wn t cause any harm t peple wrking and testing fr the vehicle. A twing hk r ring is mandatry s that it can be twed with a cable by anther vehicle and this hk r ring must resist a tractin frce f 2000N (~200 kg). These were the requirements classified especially fr fairing/bdy and interir. Hwever, fr the entire vehicle including chassis and suspensin, drive train, mtr, steering, brake system, and ther electrical cmpnents; there were specific rules classified in Shell Ec-Marathn fficial rules 2012, chapter I. Client-specified Requirements Prir t starting n any prject, the team needs t value the client s requirements fr the prduct. Similarly, in this prject; the client has sme specific requirements which are classified as belw: All systems must be cnstructed frm cmmercial ff-the-shelf parts r fabricated by the team. Systems must stay under the budget specified by NAU SAE The fairing/ bdy material shuld be cmpsed f light and strng materials that prtect the interir and the driver inside the vehicle. Mrever, the shape f the fairing shuld have innvative and creative design which culd be prudly used as a shwcase at Nrthern Arizna University.

4 Prject Descriptin Figure 1 CAD assembly mdel. The fllwing table shws the status f each requirement with the specificatins which gives the brief detail abut the result btained in the prject. Table 1 Results presented as specificatin chart. Specificatin/Requirement /Nt met Results/Cmmentary The ttal height must be between 100cm and 130cm. The ttal bdy width, The height btained fr the fairing was 108 cm and the grund clearance was 15 cm, s the height excluding rear view mirrrs, must be dimensin was satisfied. Als, the bdy width and between 120cm and 130cm. The ttal length was 127 cm and 308 cm respectively. vehicle length must be between 220cm and 350cm. The track width must be at least 100 cm fr the frnt axle and 80 cm fr the rear axle, measured between the midpints where the tires tuch the grund. The wheelbase must be at least 120 cm. This requirement was satisfied by the frame and suspensin team. The wheelbase lcatin and dimensin was determined by frame team and was satisfied. The driver s cmpartment must have a minimum height f 88 cm and a minimum width f 70 cm at the Driver s shulders. The driver had enugh rm space in the vehicle t satisfy these requirements.

5 Prject Descriptin The grund clearance must be at least 10 cm. The maximum vehicle weight (excluding the Driver) must be 205kg. but nt 100% satisfied The grund clearance is mre than 10 cm. The ttal vehicle weight was apprximately 180 kg. The fairing weight was arund 65 kg after attachments f glasses and drs. This weight requirement was met as per the shell rules but it still came ut t be ver-weight accrding t client. The bdy must cver all mechanical parts excluding wheels and suspensin, whether the vehicle is viewed frm the frnt, the rear, and the sides r frm abve. The wheels and suspensin must be fully cvered by the bdy seen frm abve and up t the axle center line when seen frm frnt r rear. The cver f wheels and suspensin must be a rigid integral part f the vehicle bdy. The dr pening must have a minimum dimensin f mm. This means the dr pening will be verified with a rectangular template f 500 x 800 mm. Any access pening mechanisms (e.g. drs) must be firmly attached t the vehicle bdy (e.g. by means f hinges, sliding rails, etc.). Adhesive tape, Velcr, etc. are nt permitted fr this purpse. The vehicle must have a rf cvering the Driver s cmpartment. A windscreen with effective wiper(s) is mandatry. The fairing cvered all the sub-parts f the vehicle while viewing frm different view. The fairing had fenders t cver the wheel and the bdy itself cvers the suspensin system. The driver was successful t get ut f vehicle in 7 sec. which was tested in cmpetitin. S, the dr was large enugh fr accessing. 2 zinc plated pin hinge were attached in each dr t fulfill this requirement. The fairing had all surfaces enclsed t fit the requirement. Lexan was used as a windscreen and it was big enugh fr clear visibility. The wiper was attached by Electrical team but it did nt cver the whle windscreen. S, bigger wiper wuld have been better.

6 Prject Descriptin Luggage space must be available fr a suitcase like bject with dimensins f 500 x 400 x 200 mm (L x H x W). This space must be easily accessible frm the utside and must include a flr and sidewalls t hld the luggage in place when the vehicle is mving. A cmpetitr supplied suitcase like bject must be placed in this space during any cmpetitin. Fr drivers requiring ballast this suitcase like bject must cntain the ballast. Vehicle bdies must nt include any external appendages that might be dangerus t ther Team members; e.g. sharp pints must have a radius f 5 cm r greater alternatively they shuld be made f fam r similar defrmable material. A twing hk r ring is mandatry n the frnt f the vehicle, s that it can be twed with a cable by anther vehicle. This hk r ring must resist a tractin frce f 2000 N (~200 kg). EPS fam material required t make the mld shuld be within the dimensin f the verall fairing by a clearance f 10 cm in each directin (x,y,z). The width must be at least 129 cm and length 310 cm and height 110 cm. The vehicle shuld meet the entire safety requirement t be able t drive in the rad. The dimensin f luggage cmpartment was nt very critical. But still the requirement was met. The luggage cmpartment in this vehicle als cvers and prtects the electrical bard. Sharp edges were avided by sanding the edges using template having radius f 5 cm. Twing hk was attached in the frame and this hk supprts the whle bdy system. A 2D CNC machine was used t cut the fam. The verall dimensin f the fam blck was 315 cm X 130 cm X 114 cm (L X W X H). All safety devices were psitined prperly making driver accessible fr it.