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RC-car remotely controlled from a computer. A demonstration of the power of Pytelemetry/telemetry. MIT Licensing.
Dependencies: BufferedSerial FRDM-TFC mbed telemetry
Example of the 'Telemetry' library, a portable communication library for embedded devices. The PC-side of this code is hosted a github.com/Overdrivr/telemetry-examples
This code uses the car from the Freescale Cup competition initially dedicated to be a line-following racing car, and turns it into a full-blown radio-controlled car.
It is using a Bluetooth serial module to provide wireless connectivity. See the repository at github.com/Overdrivr/telemetry-examples for complete instructions on wiring everthing together.
Repo : TO BE DONE
main.cpp
- Committer:
- Overdrivr
- Date:
- 2016-02-22
- Revision:
- 1:5a07069e17b6
- Parent:
- 0:c5e974040f21
- Child:
- 2:74d5233b6284
File content as of revision 1:5a07069e17b6:
#include "mbed.h" #include "FRDM-TFC/TFC.h" #include "telemetry/Telemetry.h" /* Example of the 'Telemetry' library, a portable communication library for embedded devices. The PC-side of this code is hosted a github.com/Overdrivr/telemetry-examples This code uses the car from the Freescale Cup competition initially dedicated to be a line-following racing car, and turns it into a full-blown radio-controlled car. It is using a Bluetooth serial module to provide wireless connectivity. See the repository at github.com/Overdrivr/telemetry-examples for complete instructions on wiring everthing together. Repo : TO BE DONE */ DigitalOut led(LED1); struct TM_state { float direction; float throttle; }; // Definition of the callback function void process(TM_state* carState, TM_msg* msg); int main() { // Create a Telemetry instance, running on uart at 115200 bauds Telemetry TM(115200); // a data structure to hold writeable parameters // i.e. the car direction and throttle that will be both be controlled from the laptop TM_state carState; carState.direction = 0; carState.throttle = 0; // Suscribe our custom processing function (= callback function), and pass the data structure // so that we can access it inside // This way, everytime a frame is received, Telemetry will call this function for us, // and pass the TM_state data structure to it. TM.sub(process, &carState); led = 1; // Init the TheFreescaleCup shield TFC_Init(); // Some timers... for timing :p Timer servo_timer; Timer motor_timer; Timer tm_timer; Timer print_timer; servo_timer.start(); motor_timer.start(); tm_timer.start(); print_timer.start(); // Activate the engines ! TFC_HBRIDGE_ENABLE; for(;;) { // update telemetry if(tm_timer.read_ms() > 50) { tm_timer.reset(); TM.update(); } // update servo control if(servo_timer.read_ms() > 10) { servo_timer.reset(); TFC_SetServo(0, carState.direction); } // update motor control if(motor_timer.read_ms() > 5) { motor_timer.reset(); TFC_SetMotorPWM(carState.throttle , carState.throttle); } // publish car state & blink a led if(print_timer.read_ms() > 500) { print_timer.reset(); // Publish the car parameters, so we can access them from the computer TM.pub_f32("direction",carState.direction); TM.pub_f32("throttle",carState.throttle); led = (led == 0) ? 1 : 0; // Toggle the led } } } // This is our processing function called every time a frame is received // First parameter is a pointer to the data structure we defined in main // Second parameter is a pointer to a data structure containing all info about received frame void process(TM_state* carState, TM_msg* msg) { // temp variable float value = 0.f; // If received topic == 'direction' if(strcmp(msg->topic,"direction") == 0) { // If data type matches 'float32' if(emplace_f32(msg,&value)) { // Check values in order to avoid going beyond servomotor limits if(value > 1.f) value = 1.f; if(value < -1.f) value = -1.f; carState->direction = value; } } // Idem for throttle else if(strcmp(msg->topic,"throttle") == 0) { if(emplace_f32(msg,&value)) { if(value > 1.f) value = 1.f; if(value < -1.f) value = -1.f; carState->throttle = value; } } }