ODrive/docs/migration.md

Migration Guide

Certain changes occurred between firmware versions v0.4.12 and v0.5.1 that will break existing configurations. This document is a guide for how to take a working v0.4.12 ODrive config and change it to work with firmware v0.5.1.

Unit Changes

ODrive now uses units of [turns], [turns/s], and [turns/s^2] instead of [counts], [counts/s], and [counts/s^2]. In addition, the motor controller class now has an input command of torque in [Nm] instead of current in [Amps]. In general, every user-facing parameter that has to do with position or velocity is affected by the unit change.

Note: For the torque to be in correct in [Nm] you need to configure the motor.config.torque_constant. See the updated getting started for more details.

Control Parameter Names

ODrive now uses input_pos, input_vel, and input_torque as commands instead of pos_setpoint, vel_setpoint, and current_setpoint

Guide

For a working v0.4.12 ODrive configuration, use the following equations to convert parameters as required.

• pos_gain is unaffected ( [counts/s / count] -> [turns/s / turns] )
• vel_gain is vel_gain_old * torque_constant * encoder cpr
• vel_integrator_gain is vel_integrator_gain_old * torque_constant * encoder cpr

For other values, [turns] = [counts] / [encoder cpr]. Converting [counts/s] and [counts/s^2] is similar.

Affected Variables

• axis.controller.input_pos
• axis.controller.input_vel
• axis.controller.input_torque
• axis.controller.config.vel_limit
• axis.controller.config.vel_ramp_rate
• axis.controller.config.current_ramp_rate is now axis.controller.config.torque_ramp_rate
• axis.controller.config.circular_setpoint_range
• axis.controller.config.inertia
• axis.controller.config.homing_speed
• axis.controller.pos_setpoint
• axis.controller.vel_setpoint
• axis.controller.torque_setpoint instead of axis.controller.current_setpoint
• axis.trap_traj.config.vel_limit
• axis.trap_traj.config.accel_limit
• axis.trap_traj.config.decel_limit
• axis.encoder.pos_estimate
• axis.encoder.pos_estimate_circular
• axis.encoder.vel_estimate
• axis.config.counts_per_step is now turns_per_step for the step/direction interface
• axis.sensorless_estimator.vel_estimate is in mechanical [turns/s] instead of electrical [radians/s]