January 1999. Here is a (slightly) modified version of Leo Dorst's LEGO model of Killough's mobile robot platform. See Leo's personal Technic Idea Book section for background info on this design. I made the wheel carrier somewhat more robust by using a few of the newer Technic elements. A 5 SLU(standard LEGO unit) axle with one of those nifty perpedicular axle connectors, and a couple bushings, replace the components on the drive end. Then I used some of the new 7 SLU long 1/2 width rounded beams pinned in place by 3 SLU axles to keep the wheel assemblies from pulling apart. The other major change was to use three 40 T gears instead of the five 24 T gears in the original design. This reduces backlash quite a bit as well as moving the wheels closer together. This model looked like it would be fun to build but it's even better to watch it in motion.
Click on any image for a larger view.
October 1999. It now has three rotation sensors installed to more accurately control motor speed.
December 2000. With two motors per wheel set to increase the drive torque.
