MOONBUGGY REPORT Submitted by Galgotias College of Engineering and Technology Team 1 1, Knowledge Park-2 Greater Noida, Uttar Pradesh INDIA
TEAM DETAILS Our Moonbuggy design consists of its suspension system, chassis, drive trains, steering mechanism, brake system, recumbent seat assembly, tires and the wheel assembly. Each part will be designed and assembled to allow the vehicle to withstand the engineering challenges posed by the rough lunar terrain and to meet the requirements of high strength, rigidity and good dynamic performance. The vehicle will boast an ultra-lightweight foldable design in order to minimize the payload on the space missions it may be carried on. The moonbuggy will be a human-powered allterrain vehicle with the capability to become a hybrid at a later stage. Our team consists of six student members under the guidance of one faculty advisor.the team is subdivided into three groups: Suspension & Steering, Chassis & Bodywork and Marketing & Finance. The team members are responsible for the design, fabrication and testing of the vehicle Two members will drive the vehicle over the rough course designed to simulate the lunar terrain All members will ensure that the vehicle meets all the required safety criterion TEAM MEMBERS CAPTAIN Krishna Chandra Mishra, 3rd year, GCET (Design & Analysis) MEMBERS Kartikeya Mishra, 3rd year, GCET (Pilot) Bhoomika Mansharamani, 3rd year, GCET (Co-Pilot) Mukund Singh, 3rd year, GCET (Implemented new ideas) Kuldeep Kumar, 3rd year, GCET (Material Selection & Fabrication) Lal Gee Singh, 3rd year, GCET (Material Selection, Testing & Fabrication) INTRODUCTION NASA organize the great moon buggy race every year. The main objective is to design a human powered moon buggy that would be able to contend with a simulated lunar terrain including craters, rocks, lava, ridges, inclines, and lunar soil. The design must meet NASA design requirements. REQUIREMENTS PRESCRIBED BY NASA- Vehicle should be collapsible within a 4*4*4 cube. Driver seat should be 15 inch above the ground. Two drivers including a male driver and a female driver. Vehicle should be light in weight and easy to carry. OUR DESIGN CHASSIS A single beam of square cross section(hollow) with dimensions - 60*60*1500 with thickness 4-5mm. In order to accommodate in a 4 foot cube, the frame is hinged in the center. Material used-ss 304
POWER TRANSMISSION Chain drives are used for power transmission from paddle to axle. Universal joints are used for power transmission to wheels. Vehicle will be all wheel drive. SREERING SYSTEM Butterfly steering is used for steering because it is easy to manufacture and reliable. At each side of final chain ring will be a roller clutch that attaches and delivers power to the wheels. These roller clutches will allow the allow the wheels to turn at different rates while moon buggy is turning.
NASA requires each buggy to have a minimum of a 20 ft. turning radius.
A-ARMS The A-arms have been designed to make the moon buggy as stable as possible and still maintain the necessary dimensions for the contest. To achieve this stability the A-arms will be different lengths on top and bottom. Both A-arms will be the same width of 13 inches from outside to outside but the top A-arm will be 14.81 inches long and the bottom A-arm will be 16.79 inches long. SEAT The front A-arms are 3 inch shorter than the rear arms so that front wheels will be able to roll inside the rear wheels. The riders on the moon buggy will sit in the same direction.
The seat frame will be angled to produce comfort for the riders as well as align their legs with the pedals so they can produce maximum power while they are pedaling. The seat backs will be hinged so they can fold down to meet NASA requirements of fitting into a four foot cube when the buggy is in the folded configuration. The seat material will be a strong canvas type material that is used on folding lawn chairs. This material is very strong yet lightweight and will form to the shape of the riders and help absorb some of the jarring they will feel while going over obstacles. Calculations Beam used in chassis is of square cross section The conditions assumed of loading as simply supported beam. From our design the longest member is 1.5 meters. The equation used are- Taking p=5866n, L=1.5 M, Where p is the max load applied on the beam under worst conditions, E is the young s modulus of the material, L is the length if the beam, I is the second moment of area of the beam. All calculations are done by taking factor of safety 2. The maximum deflection calculated is found to be 16 mm which is allowable. The critical load that the beam can sustain is given by the equation- 4*π 2 EI 4*π 2 *98*10 9 *(.06 4 -.056 4 ) P cr = L² = 1.5 2 The critical load that the frame can sustain is found to be 447859.82N that is far above than that as found in worst case scenario. DRIVE SHAFT DESIGN The most important components of the drive train is the drive shafts. The drive shaft must be chosen so that it does not fail during the riding if the buggy. the torque at the final drive shaft can be calculated from- F*R T f = Ф T f is the torque produced at the drive shaft, F is the force applied by the rider on the pedals.
The desired gear ratio is found to be 1.6 from T 2 Ф = T 1 The maximum torque is found to be 220 Nm. The diameter of the drive shaft is calculate from- 1.72(n (T 2 +B 2 ) 1/2 ) 1/3 d = S 1/3 d= diameter of the shaft needed in mm n= factor of safety B= maximum bending moment S= allowable stress T= maximum torque By putting T=220, B=2207,S=124.4055*10 6 all dimensions are in SI units Diameter of the drive shaft is found to be 56 mm. Our plus points in design Our design meet with all the requirements and conditions prescribed by NASA. Our design is strong enough as we have made all the calculations for worst conditions. Material used is cheap and easily available which makes the vehicle cheaper in cost. Vehicle is easy in fabrication and fabrication. Vehicle is light in weight and easy to carry. The team is working ahead with the sole belief.
Go with a clear project and a high challenge in the medium-sized businesses, show your will, achievement and motivation, test things on you own, trust the students more and more, let them in the run of time everything do on their own and you will experience a magic moment with their personality development. Below is a simplified version of the chart showing the schedule for the project BUDGET The project budget was determined by researching prices of parts on the proposed design. The total allowable spending limit of 36,220 (INR) or 664 (USD). The detailed budget continues The crucial parts were considered first and then smaller parts were added in to the total.