The curve in this diagram shows, how long the wheelchair needed to drive for each round. After three hours and something, I had to stop the test, because the batteries ran out of power. As you can see, the time for one round was always about 40 seconds.

However, this second diagram is much more interesting. It is the same as the diagram above, but the y-axis is magnified. As you can see, the time increases a lot after about 2 hours 15, because the batteries get empty. I have to say, that they weren't fully charged at the beginning of the test. But before, the wheelchair kept the time for each round quite precise. The aberration is about 5% even without a PID controller for the speed, which I thought to implement into the software later.

I also did tests in between, where I sat on the chair. Then, the rounds took about one second longer, depending on the power of the battery. (Those values were deleted in the diagram.)

I should also do a test with the wheelchair under full load, but I don't have anything which fits onto the chair with the weight of an average person, and I can hardly imagine to sit three hours in the wheelchair, driving around in my workshop, without doing anything else. Could be really boring.

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