""" These configurations is based on Austin Owens implementation: https://github.com/AustinOwens/robodog/blob/main/odrive/configs/odrive_hoverboard_config.py It was based on the hoverboard tutorial found on the Odrive Robotics website at: https://docs.odriverobotics.com/v/0.5.4/hoverboard.html """ import sys import time import math import odrive from odrive.enums import * import fibre.libfibre from fibre import Logger, Event from odrive.utils import OperationAbortedException class MotorConfig: """ Class for configuring an Odrive axis for a Hoverboard motor. Only works with one Odrive at a time. """ # Hoverboard Kv HOVERBOARD_KV = 16.0 # Min/Max phase inductance of motor MIN_PHASE_INDUCTANCE = 0 MAX_PHASE_INDUCTANCE = 0.001 # Min/Max phase resistance of motor MIN_PHASE_RESISTANCE = 0 MAX_PHASE_RESISTANCE = 0.5 # Tolerance for encoder offset float ENCODER_OFFSET_FLOAT_TOLERANCE = 0.05 def __init__(self, axis_num): """ Initalizes MotorConfig class by finding odrive, erase its configuration, and grabbing specified axis object. :param axis_num: Which channel/motor on the odrive your referring to. :type axis_num: int (0 or 1) """ self.axis_num = axis_num # Connect to Odrive print("Looking for ODrive...") self._find_odrive() print("Found ODrive.") def _find_odrive(self): # connect to Odrive self.odrv = odrive.find_any() self.odrv_axis = getattr(self.odrv, "axis{}".format(self.axis_num)) def configure(self): """ Configures the odrive device for a hoverboard motor. """ # Erase pre-exsisting configuration print("Erasing pre-exsisting configuration...") try: self.odrv.erase_configuration() except ChannelBrokenException: pass self._find_odrive() # Standard 6.5 inch hoverboard hub motors have 30 permanent magnet # poles, and thus 15 pole pairs self.odrv_axis.motor.config.pole_pairs = 15 # Hoverboard hub motors are quite high resistance compared to the hobby # aircraft motors, so we want to use a bit higher voltage for the motor # calibration, and set up the current sense gain to be more sensitive. # The motors are also fairly high inductance, so we need to reduce the # bandwidth of the current controller from the default to keep it # stable. self.odrv_axis.motor.config.resistance_calib_max_voltage = 4 self.odrv_axis.motor.config.requested_current_range = 25 self.odrv_axis.motor.config.current_control_bandwidth = 100 # Estimated KV but should be measured using the "drill test", which can # be found here: # https://discourse.odriverobotics.com/t/project-hoverarm/441 self.odrv_axis.motor.config.torque_constant = 8.27 / self.HOVERBOARD_KV # Hoverboard motors contain hall effect sensors instead of incremental # encorders self.odrv_axis.encoder.config.mode = ENCODER_MODE_HALL # The hall feedback has 6 states for every pole pair in the motor. Since # we have 15 pole pairs, we set the cpr to 15*6 = 90. self.odrv_axis.encoder.config.cpr = 90 # Since hall sensors are low resolution feedback, we also bump up the #offset calibration displacement to get better calibration accuracy. self.odrv_axis.encoder.config.calib_scan_distance = 150 # Since the hall feedback only has 90 counts per revolution, we want to # reduce the velocity tracking bandwidth to get smoother velocity # estimates. We can also set these fairly modest gains that will be a # bit sloppy but shouldn’t shake your rig apart if it’s built poorly. # Make sure to tune the gains up when you have everything else working # to a stiffness that is applicable to your application. self.odrv_axis.encoder.config.bandwidth = 100 self.odrv_axis.controller.config.pos_gain = 1 self.odrv_axis.controller.config.vel_gain = 0.02 * self.odrv_axis.motor.config.torque_constant * self.odrv_axis.encoder.config.cpr self.odrv_axis.controller.config.vel_integrator_gain = 0.1 * self.odrv_axis.motor.config.torque_constant * self.odrv_axis.encoder.config.cpr self.odrv_axis.controller.config.vel_limit = 10 # Set in position control mode so we can control the position of the wheel self.odrv_axis.controller.config.control_mode = CONTROL_MODE_POSITION_CONTROL # In the next step we are going to start powering the motor and so we # want to make sure that some of the above settings that require a # reboot are applied first. print("Saving manual configuration and rebooting...") self.odrv.save_configuration() print("Manual configuration saved.") try: self.odrv.reboot() except ChannelBrokenException: pass self._find_odrive() input("Make sure the motor is free to move, then press enter...") print("Calibrating Odrive for hoverboard motor (you should hear a " "beep)...") self.odrv_axis.requested_state = AXIS_STATE_MOTOR_CALIBRATION # Wait for calibration to take place time.sleep(10) if self.odrv_axis.motor.error != 0: print("Error: Odrive reported an error of {} while in the state " "AXIS_STATE_MOTOR_CALIBRATION. Printing out Odrive motor data for " "debug:\n{}".format(self.odrv_axis.motor.error, self.odrv_axis.motor)) sys.exit(1) if self.odrv_axis.motor.config.phase_inductance <= self.MIN_PHASE_INDUCTANCE or \ self.odrv_axis.motor.config.phase_inductance >= self.MAX_PHASE_INDUCTANCE: print("Error: After odrive motor calibration, the phase inductance " "is at {}, which is outside of the expected range. Either widen the " "boundaries of MIN_PHASE_INDUCTANCE and MAX_PHASE_INDUCTANCE (which " "is between {} and {} respectively) or debug/fix your setup. Printing " "out Odrive motor data for debug:\n{}".format(self.odrv_axis.motor.config.phase_inductance, self.MIN_PHASE_INDUCTANCE, self.MAX_PHASE_INDUCTANCE, self.odrv_axis.motor)) sys.exit(1) if self.odrv_axis.motor.config.phase_resistance <= self.MIN_PHASE_RESISTANCE or \ self.odrv_axis.motor.config.phase_resistance >= self.MAX_PHASE_RESISTANCE: print("Error: After odrive motor calibration, the phase resistance " "is at {}, which is outside of the expected range. Either raise the " "MAX_PHASE_RESISTANCE (which is between {} and {} respectively) or " "debug/fix your setup. Printing out Odrive motor data for " "debug:\n{}".format(self.odrv_axis.motor.config.phase_resistance, self.MIN_PHASE_RESISTANCE, self.MAX_PHASE_RESISTANCE, self.odrv_axis.motor)) sys.exit(1) # If all looks good, then lets tell ODrive that saving this calibration # to persistent memory is OK self.odrv_axis.motor.config.pre_calibrated = True # Check the alignment between the motor and the hall sensor. Because of # this step you are allowed to plug the motor phases in random order and # also the hall signals can be random. Just don’t change it after # calibration. print("Calibrating Odrive for encoder...") self.odrv_axis.requested_state = AXIS_STATE_ENCODER_OFFSET_CALIBRATION # Wait for calibration to take place time.sleep(30) if self.odrv_axis.encoder.error != 0: print("Error: Odrive reported an error of {} while in the state " "AXIS_STATE_ENCODER_OFFSET_CALIBRATION. Printing out Odrive encoder " "data for debug:\n{}".format(self.odrv_axis.encoder.error, self.odrv_axis.encoder)) sys.exit(1) # If offset_float isn't 0.5 within some tolerance, or its not 1.5 within # some tolerance, raise an error if not ((self.odrv_axis.encoder.config.offset_float > 0.5 - self.ENCODER_OFFSET_FLOAT_TOLERANCE and \ self.odrv_axis.encoder.config.offset_float < 0.5 + self.ENCODER_OFFSET_FLOAT_TOLERANCE) or \ (self.odrv_axis.encoder.config.offset_float > 1.5 - self.ENCODER_OFFSET_FLOAT_TOLERANCE and \ self.odrv_axis.encoder.config.offset_float < 1.5 + self.ENCODER_OFFSET_FLOAT_TOLERANCE)): print("Error: After odrive encoder calibration, the 'offset_float' " "is at {}, which is outside of the expected range. 'offset_float' " "should be close to 0.5 or 1.5 with a tolerance of {}. Either " "increase the tolerance or debug/fix your setup. Printing out " "Odrive encoder data for debug:\n{}".format(self.odrv_axis.encoder.config.offset_float, self.ENCODER_OFFSET_FLOAT_TOLERANCE, self.odrv_axis.encoder)) sys.exit(1) # If all looks good, then lets tell ODrive that saving this calibration # to persistent memory is OK self.odrv_axis.encoder.config.pre_calibrated = True print("Saving calibration configuration and rebooting...") self.odrv.save_configuration() print("Calibration configuration saved.") try: self.odrv.reboot() except ChannelBrokenException: pass self._find_odrive() print("Odrive configuration finished.") def mode_idle(self): """ Puts the motor in idle (i.e. can move freely). """ self.odrv_axis.requested_state = AXIS_STATE_IDLE def mode_close_loop_control(self): """ Puts the motor in closed loop control. """ self.odrv_axis.requested_state = AXIS_STATE_CLOSED_LOOP_CONTROL def move_input_pos(self, angle): """ Puts the motor at a certain angle. :param angle: Angle you want the motor to move. :type angle: int or float """ self.odrv_axis.controller.input_pos = angle/360.0 if __name__ == "__main__": hb_motor_config = MotorConfig(axis_num = 0) hb_motor_config.configure() print("CONDUCTING MOTOR TEST") print("Placing motor in close loop control. If you move motor, motor will " "resist you.") hb_motor_config.mode_close_loop_control() # Go from 0 to 360 degrees in increments of 30 degrees for angle in range(0, 390, 30): print("Setting motor to {} degrees.".format(angle)) hb_motor_config.move_input_pos(angle) time.sleep(5) print("Placing motor in idle. If you move motor, motor will " "move freely") hb_motor_config.mode_idle()