NASA moon buggy project

1. NASA moon buggy project Faculty Advisor: Dr. Quamrul Mazumder Engineering Science University of Michigan-Flint Team Members: Brent Morello Nicholas Kapes Anthony Reeser May 1, 2007

2. Nicholas Kapes Dr. Quamrul Mazumder Brent Morello Anthony Reeser

3. Introduction Our team built a competitive moon buggy according to NASA specifications To efficiently build a moon buggy, three main roles were formed, (design/project management, purchasing and manufacturing) The team’s basic functions are very separate, however they end up overlapping and as a result it turns out that we all participated in each of these roles in some way. As a result our team worked well because we were able to form structure, but also be flexible. Structure was also found by separating the moon buggy build, into sections, such chassis, steering, etc. Flexibility and design efficiency was achieved by allowing manufacturing to place and purchase components onto the moon buggy.

4. Baseline Plan Vs. Actual Project Progress The baseline plan only allowed for one week for each design task (chassis, steering, etc) The actual project performance proved that manufacturing needed around two weeks for each design task It should be noted that had manufacturing not been late that design would only be slightly late on a few of the tasks Numerically evaluating project timeliness is around 80% because 1/3 (design) + 1/3 (purchasing) + 1/6 (manufacturing) approximately 83%

5. Projected Cost

6. Actual Cost

7. Projected Cost Vs. Actual Cost (cont.) Our biggest cost saving success in purchasing was achieved by buying bikes from Wal-Mart, because the bikes were relatively cheap compared to buying all of the individual components. Another success with purchasing was that we caught a break on the purchasing of aluminum square tubing. Our biggest opportunity for improvement would have been the purchasing of the steel tubing, because it was over priced. It should be noted, that we did not account for all of the miscellaneous hardware (nuts, bolts, tools, etc), however the budget had enough miscellaneous charges such as machining and sheet metal. Numerically evaluating project cost we are roughly 16% over budget, thus we achieve an 84% meeting cost targets

8. Actual Moon Buggy Vs. Model Moon Buggy

9. 150 LBF Ra, Ma 150lbf 4ft Mechanical Design Statics: Cantilever beam

10. 0.25 in 0.685in 1.25 in Mechanical Design (cont.) Von misses stress and safety calculation: The beam has a safety factor of 1.4

11. 300lbf remote load Restraints Mechanical Design (cont.) FEA Statics: An FEA (finite element analysis) is used in cases where the cross section of an object is non uniform and complex to evaluate Von Misses stress, deformation and the safety factor.

12. Mechanical Design (cont.) FEA Mesh: FEA is using solid mesh elements with a 0.010 inch global mesh, with a 0.005 inch small feature refinement mesh, a Jacobian mesh matrix check and smoothly meshed surfaces

13. Mechanical Design (cont.) FEA Von misses stress safety calculation: The support beam has a safety factor of 2.4, due to the edge restraints

14. Mechanical Design (cont.) FEA Deformation calculation: The support beam has a maximum deformation in the y axis of 2.8 microns, which is negligible

15. 16.6 Moon Buggy Competitiveness By manually adjusting the caster to 16.6  we achieve a tighter cornering radius By using aluminum for the frame, the moon buggy weighs under 100lbf By making the overall frame dimensions 8ft X 4ft the moon buggy is very stable The moon buggy performance met our design targets, thus we evaluate competitiveness as 100%

16. Competition requirements The moon buggy completion requirements that were the most difficult to achieve were the 4ft cube packaging requirement and the no passenger may be below 15” from the ground. We achieved all of the moon buggy race requirements and thus the evaluation on this section is satisfactory. The moon buggy meets all competition requirements, thus we evaluate this as 100% success Foot pedal is the limiting factor for the 15” ground clearance requirement Split in frame, accompanied with a support block helps achieve 4ft cube packaging requirement

17. Overall project Evaluation To completely evaluate the overall project success though achieving the goals and tasks a numerical evaluation must take place. All of the categories are equally important, so they will be considered to be weighted equally and percentages will be assigned to cost targets, timing targets, moon buggy competition requirements and moon buggy competitiveness goals . The table below shows the evaluation for each of these categories and as you may see overall, our project ends up being a 91.75% success.