| Supported Targets | ESP32 | ESP32-S3 | | ----------------- | ----- | -------- | # MCPWM Brushed DC Motor Example (See the README.md file in the upper level 'examples' directory for more information about examples.) This example mainly illustrates how to drive a brushed DC motor by generating two specific PWM signals. This example assumes an [L298N](https://www.st.com/content/st_com/en/products/motor-drivers/brushed-dc-motor-drivers/l298.html) H-bridge driver is used to provide the needed voltage and current for brushed DC motor. This example also implements a motor control command console such that users can configure and control the motors at run time using console commands. ## How to Use Example Before project configuration and build, be sure to set the correct chip target using `idf.py set-target `. ### Hardware Required * A development board with any Espressif SoC which features MCPWM and PCNT peripheral (e.g., ESP32-DevKitC, ESP-WROVER-KIT, etc.) * A USB cable for Power supply and programming * A separate 12V power supply for brushed DC motor and H-bridge (the voltage depends on the motor model used in the example) * A motor driving board to transfer pwm signal into driving signal * A brushed DC motor, e.g. [25GA370](http://www.tronsunmotor.com/data/upload/file/201807/e03b98802b5c5390d6570939def525ba.pdf) * A quadrature encoder to detect speed Connection : ``` Power(12V) | v +----------------+ +--------------------+ | | | H-Bridge | | GND +------------>| | +--------------+ | | | | | | | GPIO15 +----PWM0A--->| IN_A OUT_A +----->| Brushed | | | | | | DC | | GPIO16 +----PWM0B--->| IN_A OUT_B +----->| Motor | | | | | | | | ESP | +--------------------+ | | | | +------+-------+ | | | | | +--------------------+ | | VCC3.3 +------------>| Encoder | | | | | | | | GND +------------>| |<------------+ | | | | | GPIO18 |<---PhaseA---+ C1 | | | | | | GPIO19 |<---PhaseB---+ C2 | | | | | +----------------+ +--------------------+ ``` NOTE: If some other GPIO pins (e.g., 13/14) are chosen as the PCNT encoder pins, flashing might fail while the wires are connected. If this occurs, please try disconnecting the power supply of the encoder while flashing. ### Build and Flash Run `idf.py -p PORT flash monitor` to build, flash and monitor the project. (To exit the serial monitor, type ``Ctrl-]``.) See the [Getting Started Guide](https://idf.espressif.com/) for full steps to configure and use ESP-IDF to build projects. ## Example Output Run the example, you will see the following output log: ```bash ... Testing brushed motor with PID... initializing mcpwm gpio... Configuring Initial Parameters of mcpwm... Type 'help' to get the list of commands. Use UP/DOWN arrows to navigate through command history. Press TAB when typing command name to auto-complete. ================================================================= | Example of Motor Control | | | | 1. Try 'help', check all supported commands | | 2. Try 'config' to set control period or pwm frequency | | 3. Try 'pid' to configure pid paremeters | | 4. Try 'expt' to set expectation value and mode | | 5. Try 'motor' to start motor in several seconds or stop it | | | ================================================================= Default configuration are shown as follows. You can input 'config -s' to check current status. ----------------------------------------------------------------- Current Configuration Status Configuration Period = 10 ms PID = enabled PID - Increment Kp = 0.800 Ki = 0.000 Kd = 0.100 Expectation - Triangle init = 30.000 max = 50.000 min = -50.000 pace = 1.000 MCPWM Frequency = 1000 Hz Motor Running seconds = 10 ----------------------------------------------------------------- mcpwm-motor> ``` ### Check all supported commands and their usages * Command: `help` ```bash mcpwm-motor> help help Print the list of registered commands config config -s Enable or disable PID and set motor control period --pid= Enable or disable PID algorithm -T, --period= Set motor control period -s, --show Show current configurations expt expt -i -m -p --max --min -50 Set initial value, limitation and wave mode of expectation. Both dynamic and static mode are available --max= Max limitation for dynamic expectation --min= Min limitation for dynamic expectation -p, --pace= The increasing pace of expectation every 50ms -i, --init= Initial expectation. Usually between -100~100 -m, --mode= Select static or dynamic expectation wave mode. 'fixed' for static, 'tri' for triangle, 'rect' for rectangle pid pid -p -i -d -t Set parameters and type for PID algorithm -p, --kp= Set Kp value for PID -i, --ki= Set Ki value for PID -d, --kd= Set Kd value for PID -t, --type= Select locational PID or incremental PID motor motor -u 10 Start or stop the motor -u, --start= Set running seconds for motor, set '0' to keep motor running -d, --stop Stop the motor ``` ### Check status * Command: `config -s` ```bash mcpwm-motor> config -s ----------------------------------------------------------------- Current Configuration Status Configuration Period = 10 ms PID = enabled PID - Increment Kp = 0.800 Ki = 0.000 Kd = 0.100 Expectation - Triangle init = 30.000 max = 50.000 min = -50.000 pace = -1.000 MCPWM Frequency = 1000 Hz Motor Running seconds = 10 ----------------------------------------------------------------- ``` ### Enable or disable PID * Command: `config --pid ` * 'y' - enable PID * 'n' - disable PID ```bash mcpwm-motor> config --pid n config: pid disabled mcpwm-motor> config --pid y config: pid enabled ``` ### Set PID parameters * Command: `pid -p -i -d -t ` * 'p' - proportion value * 'i' - integral value * 'd' - differential value * 't' - PID calculation type (locational or incremental). ```bash mcpwm-motor> pid -p 0.8 -i 0.02 -d 0.1 -t inc pid: kp = 0.800 pid: ki = 0.020 pid: kd = 0.100 pid: type = increment ``` ### Set expectation parameters * Command: `expt -i -m -p --max --min ` * 'i' - initial duty if you set mode 'fixed' * 'm' - expectation mode. 'fixed' means the expectation will never change, 'tri' means the expectation will changes with trigonometric wave, 'rect' means the expectation will changes with rectangular wave * 'p' - the setp size of expectation changed in every 50ms, it can adjust the expectation changing speed * 'max' - the maximum limitation of expectation * 'min' - the minimum limitation of expectation ```bash mcpwm-motor> expt -i 40 -m rect -p 1.5 --max 80 --min -60 expt: init = 40.000 expt: max = 80.000 expt: min = -60.000 expt: pace = 1.500 expt: mode = rectangle ``` ### Start or stop motor * Command: `motor -u ` * Command: `motor -d` * 'u' - start the motor in seconds, if is 0, the motor won't stop until 'motor -d' is inputed * 'd' - stop the motor right now ```bash mcpwm-motor> motor -u 10 motor: motor starts to run in 10 seconds mcpwm-motor> 1 2 3 4 5 6 7 8 9 10 Time up: motor stoped ``` ## Troubleshooting * Make sure your ESP board and H-bridge module have been connected to the same GND panel. For any technical queries, please open an [issue](https://github.com/espressif/esp-idf/issues) on GitHub. We will get back to you soon.