Finished all of the test runs for the Motors vs. Tires combinations. I originally planned on making a 10 meter long track. But I didn’t want to work outside, and didn’t want to drag all of my stuff to a gymnasium and explain what I was doing to every random person that stopped by. Luck would have it that I have enough room in my house to set up a 3 meter track and thanks to the benefit of averages I could simply run each combination down this track say three times for a total effective length of 9 meters (pretty close to my original desire) and still get a good chunk of data. Now I have five different motors, and 17 different types of tires for this test. That results in 85 different motor/tire combinations, then I ran each test three times -that is 255 runs. Each run was three meters, so I drove my little LEGO vehicle 765 meters! That’s about 0.48 miles, which isn’t far to walk or drive, but is a long way to chase a little LEGO vehicle for sure.
I used the same axles and gear reduction (46.656:1) for all of these tests. The most power hungry motor/tire combination was burning about 38 Joules per meter (yeah about 114 watts for one 2 min. 30 sec. run), the best combo resulted approximately 1.5 J/m (covered the same distance in about 20 seconds), that's a 76:1 ratio! Again this is a very slow gear ratio, I'm expecting higher gears to turn the tables a bit.
Unfortunately I have to work tomorrow. But I have have Tuesday to Thursday off, so I will chart and graph everything out for you guys. I still need to know if there are any axle or gear trains you are interested in.
"The more you know, the more you know, the less you know."