As set up for the last post, my micromouse Decimus is performing reasonably well on the ground. So far. The data plots show some features that are a little bit curious. However, my concerns over the apparent error in the endpoint were a little misleading. The recorded error is derived from the integral of the set speed and the total count from the wheel encoders. Thus, it does not represent an actual error on the ground…
With new tyres and a tweak to the acceleration profilers it is time to grab some data from Decimus again. The tyre seem to give me reliable grip up to 4m/s/s. They will probably manage more but I seem to have other control issues then. In any case, a dusty maze will soon put paid to that. For this trial, the mouse was commanded to move forward 4 squares with no limit on its top speed…
It is true, I am losing my grip. A while ago I posted a link to a Japanese site demonstrating the grip available from a particular micromouse. A common way of doing this is to lock the wheels and place the mouse on a tilting surface. As the slope of the surface is increased, the downforce available to the tyres is progressively reduced until the mouse slips. Part of the downforce is lost due to the angle alone and is proportional to the tangent of the slope.
The schools competition includes a head-to-head drag race called Formula 1. If you want to know how fast you have to be, read this.The Formula 1 Rat Race track is straight and 7.2m long. At the start end is an area 375mm long where the rat starts from. At the end is a 1.2m long area for the mouse to come to a rest. It must not overshoot this area of penalties will be incurred that will almost certainly eliminate the rat from the competition. (more…)