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vortexntnu / rov-control

Complete control system for Vortex' ROV
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Update manipulator_interface to Otterholms hardware #63

Closed aksell closed 6 years ago

aksell commented 6 years ago

The manipulator_interface on Otterholm will run on a nanopi NEO 2+ with a custom nanopi shield. For now there is only support for a single stepper motor with direction control. The manipulator_interface will be updated as new actuators are integrated into the design. The stepper shields enable pin is not accessible. This is worked around by using the two PWM inputs to the stepper driver as an ad hoc enable pin.

mortenfyhn commented 6 years ago

Regarding performance: It's really bad, because the node has to wake up every 60.0 / (STEPPER_NUM_STEPS * STEPPER_RPM) seconds, which means 200 times a second for a 200 step stepper running at one rotation a second. Then each time it wakes it has to set four GPIOs. So it's a lot of work. Then again, if the computer isn't doing that much else, it should be fine. It would be interesting to see CPU load in normal operation (while spinning) compared to CPU load when only using one of the four pins, to see if the load is mostly waking up or mostly real work.

aksell commented 6 years ago

Running the node on the NanoPi NEO 2+ uses 12% of the CPU resources and 4.9% of the MEM.