Zanta
Joined 11 years ago
Joined 11 years ago
Related, I'm very impressed by his speed. I ride about 9 miles to and from work and it takes me ~35-40 minutes door to door.
I'm frequently disappointed by really good ideas that could be presented in a dozen pages being stretched to occupy 200 (e.g. Deep Work)
The wheels allowed some neat driving tricks, but it also made it really difficult to drive in a straight line. You don't get the normal tracking behaviour that wheels give you, and differences in traction from wheel to wheel also tend to distort your course. Adding a gyro for use in a closed-loop angular control system really helped this a lot.
[1] https://en.wikipedia.org/wiki/Omni_wheel [2] http://willbeattie.ca/Projects/Twitch/Twitch.html
Do the steppers have encoders on them? If not, the machine can't do closed loop control. It can keep track of where the rotor should be based on counting the steps of coils it has energized, but it has no way of directly keeping track of the rotor. A large enough torque resisting the rotor's rotation can cause the rotor to skip steps, but this doesn't influence the energizing of coils in the stator so the machine has no idea that anything has gone wrong.
An encoder lets you directly measure what's going on with the rotor (and therefore the shaft of the motor). You basically keep track of where you should be (based on counting the steps delivered to the stator coils) then use the encoder to validate. e.g. 'I've sent 12 steps so I should be 48 degrees from where I started. My encoder is reading 26 degrees, so I must have skipped steps somewhere along the way.'
https://www.sciencedaily.com/releases/2011/03/110307130215.h...
I was mostly trying to address the direct cause-and-effect conclusion the parent comment was making with breathing hard == losing weight