I'm not sure odrive can be used on the last version of Python, so I have not updated it from ``
If you are not sure what configuration is currently saved in the ODrive it is better to run first the
initial_calibration.py file. The pinched noise is totally normal even if it seems unbearable.
If no error has been detected, you are good to go!
Run the main.py file. You should see the GUI appear.
If you want a simple understanding of the code, you can read and run the cadence_control.py file.
/!\ Once the package is installed the imports will be from the package, not from the files in the repository. If you are developing and doing a lot of changes, it is better to uninstall the package and run the files from an IDE or a terminal. To install the package, write in a terminal:
python setup.py install
You might need the sudo command:
sudo python setup.py install
Please note that you must have registered your hardware information in the hardware_and_security.json file.
If any information needs to be changed, the package must be reinstalled.
Then, you will be able to start the ergocycle with the command :
start_ergocycle
and to read any saved data with the command:
read_ergocycle_file file_path
The relays are not controlled by the Odrive, they are there to ensure that when the power source that powers the Odrive is sut down, the current cannot go into it. As soon as the Odrive is powered, the relays are too and the motor is directly controlled by the Odrive. To work, if the Odrive is connected to the COM pins and the motor to the NO pins, the COM pins need to be connected to the High pins (so the normally open relay closes when alimented).
There are two gear stages. The first one has 8 teeth at the entry and 36 (motor) at the exit (blue gear). The second one has supposedly (according to my researches and check on the hardware) 10 teeth at the entry and 91 at the exit. The reduction ratio is then Ze/Zs = ws/we = 8/36*10/91
2022/02/09:
- Firmware: 0.5.5, a priori the last firmware available for the Odrive v3.6 56V (end of life)
- To update the firmware on the Raspberry, use
sudo odrivetool dfu path/to/firmware/file.elf
- To update the firmware on the Raspberry, use
- Software: odrive 0.6.3.post0, the latest version at this time
- To update the software on the Raspberry, use
pip install odrive==0.6.3.post0
- To update the software on the Raspberry, use
The first step is to determine the resisting torque of the motr. The resisting torque is the minimum torque that the
motor has to apply to make the pedals move.
To do so, you must use the torque control on the system with the neutral load (just the pedals, not any additional
load). The torque profile must be a ramp and the torque at which the motor is moving is the resisting torque. You
should do it several times in order to have a precise value. It is advised to do it for each rotation direction and with
different torque_ramps.
At this point, we don't know the torque constant, so we can only have the corresponding current.
The script find_resisting_torque/resisting/torque.py allows to compute the current corresponding to the resisting
torque from .json files obtained with the find_resisting_torque/find_resisting_torque.py on the motor. A priori
the motor won't turn if it as less current than this resisting_current.
Every calibration must be done without mechanical load nor watchdog since the motor has to reboot several times.
The complete calibration must be done without any mechanical load.
The watchdog timeout can't be as little as the user wants.
For instance, for a feeding time of 0.01, the watchdog can't be as small as 0.05.
I've set it to 0.1.
I had trouble connecting the Odrive to the Raspberry Pi. The solution that worked for me was to write in a terminal:
echo 'SUBSYSTEM=="usb", ATTR{idVendor}=="1209", ATTR{idProduct}=="0d[0-9][0-9]", MODE="0666"' | sudo tee /etc/udev/rules.d/91-odrive.rules
sudo udevadm control --reload-rules
sudo udevadm trigger
To test the connection a simple script is sufficient :
import odrive
print("Look for an odrive ...")
odrive.find_any()
print("Found")
Or when launching odrivetool in a terminal, it should be written :
ODrive control utility v0.5.4
Connected to ODrive 206F3694424D as odrv0
/!\ If a script using the connection to the Odrive is running, you cannot connect to the Odrive through odrivetool
The simple test that should work before trying anything else is :
odrv0.axis0.requested_state = AXIS_STATE_FULL_CALIBRATION_SEQUENCE
I had trouble controlling the motor with the relay. When connecting it directly to the Odrive it worked.
Verify you have :
resistance_calib_max_voltage > calibration_current * phase_resistance
resistance_calib_max_voltage < 0.5 * vbus_voltage
For me (TSDZ2 connected directly to the Odrive), it worked with the following config :
I_bus_hard_max: inf (float)
I_bus_hard_min: -inf (float)
I_leak_max: 0.10000000149011612 (float)
R_wL_FF_enable: False (bool)
acim_autoflux_attack_gain: 10.0 (float)
acim_autoflux_decay_gain: 1.0 (float)
acim_autoflux_enable: False (bool)
acim_autoflux_min_Id: 10.0 (float)
acim_gain_min_flux: 10.0 (float)
bEMF_FF_enable: False (bool)
calibration_current: 30.0 (float)
current_control_bandwidth: 100.0 (float)
current_lim: 35.0 (float)
current_lim_margin: 8.0 (float)
dc_calib_tau: 0.20000000298023224 (float)
inverter_temp_limit_lower: 100.0 (float)
inverter_temp_limit_upper: 120.0 (float)
motor_type: 0 (uint8)
phase_inductance: 2.409255648672115e-05 (float)
phase_resistance: 0.04511798173189163 (float)
pole_pairs: 8 (int32)
pre_calibrated: True (bool)
requested_current_range: 25.0 (float)
resistance_calib_max_voltage: 10.0 (float)
torque_constant: 0.20999999344348907 (float)
torque_lim: inf (float)
Setting the odrv0.axis0.controller.config.control_mode, the odrv0.axis0.controller.config.input_mode and the
odrv0.axis0.requested_state must be done only once and not between each change of position or velocity !