pypot
pypot copied to clipboard
poppy-project
Support of multiturn mode for MX motors for suspended pypot creatures
For suspended creatures (hung by a string) we would need to take advantage of the multi-turn mode of the MX motors so that we can stick a pulley on the motor rolling a string like a winch. More generally : there are three modes : joint, wheel and multiturn. For the joint mode, all is OK For the wheel mode, set angle limit registers to 0 (not possible in the json since angle limits are converted) For joint mode, set angle limits to the one you want For multi-turn mode, set angle limits to 4095. For multi turn mode, we should add two others properties : multi-turn offset and resolution divider.
I wanted to add it by myself but it is not so simple.
Hi @ThotAlion,
I never had the opportunity to play with the multi-turn mode and I don't really have MX motors around.
But let me know where you found the difficulties to add those features and I'll try to help. This would be a cool enhancement for pypot. Do not hesitate to open a WIP pull request where we could directly work and discuss this.
No it's still an open issue. A few pointers to help out anyone willing to work on this:
-
As @ThotAlion pointed out, to enable multi turn mode you need to set a specific angle limit. This can be done here: https://github.com/poppy-project/pypot/blob/69814e9fe8a7db1f693b5af1d6a50ed184bfb8eb/pypot/dynamixel/io/io.py#L20-L53 and here: https://github.com/poppy-project/pypot/blob/69814e9fe8a7db1f693b5af1d6a50ed184bfb8eb/pypot/dynamixel/conversion.py#L327-L330
-
Adding the two extra properties (offset and resolution divider) can be done at the end of the io.py file: https://github.com/poppy-project/pypot/blob/master/pypot/dynamixel/io/io.py by adding a new control with the correct spec from robotis support website. Such as in here: https://github.com/poppy-project/pypot/blob/69814e9fe8a7db1f693b5af1d6a50ed184bfb8eb/pypot/dynamixel/io/io.py#L121-L126
This should be a good start!