Derivation of the original Mechaduino code from jcchurch13.
- added an enable pin (pin 2, only 3.3 V compatible)
- Menu entry for generating a step response
- Menu entry for generating a dirac delta function
- deleted all modes other than position
- changed all float to integer operations
- added some filtering to the effort and D-Term
- Changed the frequency of the PID loop to 5 kHz
- Encoder readings are placed in its own ISR that runs with 10 kHz (oversampling)
- maximal step frequency = 40 kHz
- changed the PWM resolution from 8 bit to 9 bit
- PID auto tuning
- The lookup table is now in its own file (lookup_table.cpp)
- The Parameters are now in Configuration.cpp
- Added Language file for easy translation
- added an invert direction setting
- simple error register to save if an error occurred
- LED shows errors by different blinking patterns
- downhill simplex algorithm to fine tune the pid settings
If an error occures the led will switch from constant on to different patterns. These patterns are separated from each other by a longer pause. After this pause one pattern will be shown and then after the pause the next pattern will be shown.
| Pattern | Error |
|---|---|
| Fast blinking | Timing error. This can occur if the mechaduino receives too much steps. Consider lowering your microsteps or limit the maximal speed |
| Long on | maximal error was reached |
| Long on, one flash | the maximal current was reached |
| Long on, two flashs | the lookup table shows some errors |
To get an list of the possible commands send help over the serial monitor
| Command | Description | Arguments |
|---|---|---|
| help | prints this menu | |
| calibrate | starts the calibration routine | |
| diagnose | read Encoder Diagnostics | |
| state | shows and sets the motor state | -on, -off |
| stream | streams servo parameters | -f {int}, -on, -off |
| parameter | Get or set parameter | -set {-parameter} {value}, -get |
| error | get or reset the error register | -reset |
| dirac | generates a Delta-Distribution | -f {int} |
| response | generates a step response | -f {int}, -s {int} |
| error | get or reset the error register | -reset |
| autotune | PID auto tune | -c {byte}, -d |
| downhill | Downhhill simplex algorithm | -f {int}, -v {int}, -o |
| testmove | Starts a testmove for the servo | -f {int}, -v {int}, -o |
| interrupt | Starts or stops the ISR | -TC5 {bool}, -TC4 {bool} |
| Command | Description |
|---|---|
| parameter -set -Kp 1.095 | Sets the proportional gain of the servo to 1.095 |
| testmove -f 2500 -v 60 | Starts a test move with the velocity of 60 mm/s and a sampling rate of 2500 Hz |
| testmove -v 60 -o | Starts a test move with the velocity of 60 mm/s and the default sampling rate of 5000 Hz. Outputs the sampled points to the serial monitor |
- Live view/stream motor parameter (angle, error, effort, ...)
- generate and analyze different test moves with different sampling rates (step response, dirac delta function, ...)
- change parameters without the need of serial commands
- generate a configuration file
- Log streamed motor parameter as txt or csv file
All Mechaduino related materials are released under the Creative Commons Attribution Share-Alike 4.0 License https://creativecommons.org/licenses/by-sa/4.0/
Much of the work is based on Mechaduino project: https://github.com/jcchurch13/Mechaduino-Firmware
If you want to support me for further improvements and things like that, you can send me a small kickback with PayPal
