We will use the
<odrv> as a placeholder for any ODrive object. Every ODrive controller is an ODrive object. In
odrivetool and the Web GUI this is usually
Furthermore we use
<axis> as a placeholder for any axis, which is an attribute of an ODrive object (for example
An axis represents where the motors are connected.
The current status of the ODrive can be observed by the color the LED:
blue/teal: The ODrive is idle. It will not move, and has no errors.
green: The ODrive is active and running.
red: An error has occurred and the ODrive is disabled. Please refer to the troublshooting page for more information.
For the most part, both axes on the ODrive can be controlled independently.
The current state of an axis is indicated by
The user can request a new state by assigning a new value to
The default state after startup is
A description of all states can be found
By default, the ODrive takes no action at startup and goes to idle immediately. In order to change what startup procedures are used, set the startup procedures you want to True. The ODrive will sequence all enabled startup actions selected in the order shown below.
here for a description of each state.
<axis>.controller.input_torque= <torque in Nm>
Encoder Position and Velocity
Motor Current and Torque Estimation
View the commanded motor current with
View the measured motor current with
If you find that this returns noisy data then use the command motor current instead. The two values should be close so long as you are not approaching the maximum achievable rotational velocity of your motor for a given supply voltage, in which case the commanded current may become larger than the measured current.
Using the motor current and the known KV of your motor you can estimate the motors torque using the following relationship:
Torque [N.m] = 8.27 * Current [A] / KV
Saving the Configuration
All variables that are part of a
[...].config object can be saved to non-volatile memory on the ODrive, so they persist after you remove power.
The relevant commands are:
<odrv>.serial_number: A number that uniquely identifies your device. When printed in upper case hexadecimal (
hex(<odrv>.serial_number).upper()), this is identical to the serial number indicated by the USB descriptor.
An example where this is useful is when you have integrated ODrive + Motor units which are assembled or handled separately from the rest of the robot, and you need to attach some user-defined calibration or identification data to each drive unit individually.
Note that the ODrive only supports a limited amount of config write cycles, so it is not recommened to use this for dynamic data.
For larger data or dynamic data, consider using storage on the host side.