The judging for the Twin Cities Science and Engineering Fair began Friday and at the beginning of the week, I had yet to test the robot on the ground. Not to mention, it was -10 below all week so it wasn't exactly ideal testing conditions. But I was able to test Wednesday on the ground and the tests were a success! It could pull me (160 lbs) up a 30 degree incline covered in snow and ice as you can see in the video below. I was very pleased with the test results, but there were a few issues that need to be resolved.
- The first is that the shock absorbers were too stiff. So I disassembled them to see if I could reduce the force needed to compress the shock absorber and I found that the shock absorbers were sent to me faulty. Usually there is a gas- typically nitrogen- found in the cylinder that is responsible for dampening, but the only thing that was doing the dampening was the coil itself and thats just bad. So I need to find some gas springs to replace these.
- The wire connected to the relay coils is too fragile and often tears when performing maintenance. 24 gauge wire with thicker strands (larger diameter) and a more heavy duty insulation must be used
- At high speeds, there is too much slack in the tracks so they must be tightened to prevent undulations
Check out this test video below
Now, onto the fair! The judges loved my project and I had some great discussions with them on why I made certain decisions on some design aspects and what not. I felt I did a good job explaining my project. It's a bit difficult to explain such a extensive project that has taken me 6 months into a ten minute presentation so I had to condense some things. The judges appreciated the hard work I've put into this and the quality design I engineered and they commemorated me on that
It paid off!
I was selected as finalist to compete at the international science and engineering fair (ISEF) in Los Angeles in May. This is where "more than 1,600 high school students from over 70 countries, regions, and territories to showcase their independent research and compete for more than $4 million in awards."
I was also awarded
- Top engineering awarded by Isthmus Engineering
- Top engineering project awarded by Air Force ROTC and Army
- Marscon Award for Excellence in the scientific process
- Selected as finalist to compete at the State Science and Engineering Fair
The military really liked my project because they saw the potential this project showed for medical evacuations in wartime situations.
Well, now its time to get back down to business with the VES (Victim Extraction System) and getting the suspension system properly functioning. I just ordered the actuators from Progressive Automations for over $600! Its a large investment, but I think it will pay off.
As for the suspension, I am going to replace the current shock absorbers with gas springs for dampening in combination with torsion springs for rebound/ return. Now the difficult part is finding a product with the correct specs.