/* Copyright (C) 2013-2015 Kristian Lauszus, TKJ Electronics. All rights reserved. This software may be distributed and modified under the terms of the GNU General Public License version 2 (GPL2) as published by the Free Software Foundation and appearing in the file GPL2.TXT included in the packaging of this file. Please note that GPL2 Section 2[b] requires that all works based on this software must also be made publicly available under the terms of the GPL2 ("Copyleft"). Contact information ------------------- Kristian Lauszus, TKJ Electronics Web : http://www.tkjelectronics.dk e-mail : kristianl@tkjelectronics.dk This is the algorithm for the Balanduino balancing robot. It can be controlled by either an Android app or a computer application via Bluetooth. The Android app can be found at the following link: https://github.com/TKJElectronics/BalanduinoAndroidApp The Processing application can be found here: https://github.com/TKJElectronics/BalanduinoProcessingApp A dedicated Windows application can be found here: https://github.com/TKJElectronics/BalanduinoWindowsApp It can also be controlled by a PS3, PS4, Wii or a Xbox controller. Furthermore it supports the Spektrum serial protocol used for RC receivers. For details, see: http://balanduino.net/ */ /* Use this to enable and disable the different options */ #define ENABLE_TOOLS #define ENABLE_SPP #define ENABLE_PS3 #define ENABLE_PS4 #define ENABLE_WII #define ENABLE_XBOX #define ENABLE_ADK #define ENABLE_SPEKTRUM #include "Balanduino.h" #include // Standard Arduino header #include // Official Arduino Wire library #include // Official Arduino SPI library #ifdef ENABLE_ADK #include #endif // These are all open source libraries written by Kristian Lauszus, TKJ Electronics // The USB libraries are located at the following link: https://github.com/felis/USB_Host_Shield_2.0 #include // Kalman filter library - see: http://blog.tkjelectronics.dk/2012/09/a-practical-approach-to-kalman-filter-and-how-to-implement-it/ #ifdef ENABLE_XBOX #include #endif #ifdef ENABLE_SPP #include #endif #ifdef ENABLE_PS3 #include #endif #ifdef ENABLE_PS4 #include #endif #ifdef ENABLE_WII #include #endif // Create the Kalman library instance Kalman kalman; // See https://github.com/TKJElectronics/KalmanFilter for source code #if defined(ENABLE_SPP) || defined(ENABLE_PS3) || defined(ENABLE_PS4) || defined(ENABLE_WII) || defined(ENABLE_XBOX) || defined(ENABLE_ADK) #define ENABLE_USB USB Usb; // This will take care of all USB communication #else #define _usb_h_ // Workaround include trap in the USB Host library #include // Include this from the USB Host library #endif #ifdef ENABLE_ADK // Implementation for the Android Open Accessory Protocol. Simply connect your phone to get redirected to the Play Store ADK adk(&Usb, "TKJ Electronics", // Manufacturer Name "Balanduino", // Model Name "Android App for Balanduino", // Description - user visible string "0.6.3", // Version of the Android app "https://play.google.com/store/apps/details?id=com.tkjelectronics.balanduino", // URL - web page to visit if no installed apps support the accessory "1234"); // Serial Number - this is not used #endif #ifdef ENABLE_XBOX XBOXRECV Xbox(&Usb); // You have to connect a Xbox wireless receiver to the Arduino to control it with a wireless Xbox controller #endif #if defined(ENABLE_SPP) || defined(ENABLE_PS3) || defined(ENABLE_PS4) || defined(ENABLE_WII) #define ENABLE_BTD #include // Some dongles can have a hub inside USBHub Hub(&Usb); // Some dongles have a hub inside BTD Btd(&Usb); // This is the main Bluetooth library, it will take care of all the USB and HCI communication with the Bluetooth dongle #endif #ifdef ENABLE_SPP SPP SerialBT(&Btd, "Balanduino", "0000"); // The SPP (Serial Port Protocol) emulates a virtual Serial port, which is supported by most computers and mobile phones #endif #ifdef ENABLE_PS3 PS3BT PS3(&Btd); // The PS3 library supports all three official controllers: the Dualshock 3, Navigation and Move controller #endif #ifdef ENABLE_PS4 //PS4BT PS4(&Btd, PAIR); // You should create the instance like this if you want to pair with a PS4 controller, then hold PS and Share on the PS4 controller // Or you can simply send "CPP;" to the robot to start the pairing sequence // This can also be done using the Android or via the serial port PS4BT PS4(&Btd); // The PS4BT library supports the PS4 controller via Bluetooth #endif #ifdef ENABLE_WII WII Wii(&Btd); // The Wii library can communicate with Wiimotes and the Nunchuck and Motion Plus extension and finally the Wii U Pro Controller //WII Wii(&Btd,PAIR); // You will have to pair with your Wiimote first by creating the instance like this and the press 1+2 on the Wiimote or press sync if you are using a Wii U Pro Controller // Or you can simply send "CPW;" to the robot to start the pairing sequence // This can also be done using the Android or via the serial port #endif void setup() { /* Setup buzzer pin */ buzzer::SetDirWrite(); /* Read the PID values, target angle and other saved values in the EEPROM */ if (!checkInitializationFlags()) { readEEPROMValues(); // Only read the EEPROM values if they have not been restored #ifdef ENABLE_SPEKTRUM if (cfg.bindSpektrum) // If flag is set, then bind with Spektrum satellite receiver bindSpektrum(); #endif } else { // Indicate that the EEPROM values have been reset by turning on the buzzer buzzer::Set(); delay(1000); buzzer::Clear(); delay(100); // Wait a little after the pin is cleared } /* Initialize UART */ Serial.begin(115200); /* Setup encoders */ leftEncoder1::SetDirRead(); leftEncoder2::SetDirRead(); rightEncoder1::SetDirRead(); rightEncoder2::SetDirRead(); leftEncoder1::Set(); // Enable pull-ups leftEncoder2::Set(); rightEncoder1::Set(); rightEncoder2::Set(); #if BALANDUINO_REVISION < 13 // On the new revisions pin change interrupt is used for all pins attachInterrupt(digitalPinToInterrupt(leftEncoder1Pin), leftEncoder, CHANGE); attachInterrupt(digitalPinToInterrupt(rightEncoder1Pin), rightEncoder, CHANGE); #endif #if defined(PIN_CHANGE_INTERRUPT_VECTOR_LEFT) && defined(PIN_CHANGE_INTERRUPT_VECTOR_RIGHT) /* Enable encoder pins interrupt sources */ #if BALANDUINO_REVISION >= 13 *digitalPinToPCMSK(leftEncoder1Pin) |= (1 << digitalPinToPCMSKbit(leftEncoder1Pin)); *digitalPinToPCMSK(rightEncoder1Pin) |= (1 << digitalPinToPCMSKbit(rightEncoder1Pin)); #endif *digitalPinToPCMSK(leftEncoder2Pin) |= (1 << digitalPinToPCMSKbit(leftEncoder2Pin)); *digitalPinToPCMSK(rightEncoder2Pin) |= (1 << digitalPinToPCMSKbit(rightEncoder2Pin)); /* Enable pin change interrupts */ #if BALANDUINO_REVISION >= 13 *digitalPinToPCICR(leftEncoder1Pin) |= (1 << digitalPinToPCICRbit(leftEncoder1Pin)); *digitalPinToPCICR(rightEncoder1Pin) |= (1 << digitalPinToPCICRbit(rightEncoder1Pin)); #endif *digitalPinToPCICR(leftEncoder2Pin) |= (1 << digitalPinToPCICRbit(leftEncoder2Pin)); *digitalPinToPCICR(rightEncoder2Pin) |= (1 << digitalPinToPCICRbit(rightEncoder2Pin)); #elif BALANDUINO_REVISION >= 13 #error "Please define "PIN_CHANGE_INTERRUPT_VECTOR_LEFT" and "PIN_CHANGE_INTERRUPT_VECTOR_RIGHT" in Balanduino.h" #endif /* Set the motordriver diagnostic pins to inputs */ leftDiag::SetDirRead(); rightDiag::SetDirRead(); /* Setup motor pins to output */ leftPWM::SetDirWrite(); leftA::SetDirWrite(); leftB::SetDirWrite(); rightPWM::SetDirWrite(); rightA::SetDirWrite(); rightB::SetDirWrite(); /* Set PWM frequency to 20kHz - see the datasheet http://www.atmel.com/Images/Atmel-8272-8-bit-AVR-microcontroller-ATmega164A_PA-324A_PA-644A_PA-1284_P_datasheet.pdf page 129-139 */ // Set up PWM, Phase and Frequency Correct on pin 18 (OC1A) & pin 17 (OC1B) with ICR1 as TOP using Timer1 TCCR1B = (1 << WGM13) | (1 << CS10); // Set PWM Phase and Frequency Correct with ICR1 as TOP and no prescaling ICR1 = PWMVALUE; // ICR1 is the TOP value - this is set so the frequency is equal to 20kHz /* Enable PWM on pin 18 (OC1A) & pin 17 (OC1B) */ // Clear OC1A/OC1B on compare match when up-counting // Set OC1A/OC1B on compare match when down-counting TCCR1A = (1 << COM1A1) | (1 << COM1B1); #ifdef ENABLE_USB if (Usb.Init() == -1) { // Check if USB Host is working Serial.print(F("OSC did not start")); buzzer::Set(); while (1); // Halt } #endif /* Attach onInit function */ // This is used to set the LEDs according to the voltage level and vibrate the controller to indicate the new connection #ifdef ENABLE_PS3 PS3.attachOnInit(onInitPS3); #endif #ifdef ENABLE_PS4 PS4.attachOnInit(onInitPS4); #endif #ifdef ENABLE_WII Wii.attachOnInit(onInitWii); #endif #ifdef ENABLE_XBOX Xbox.attachOnInit(onInitXbox); #endif /* Setup IMU */ Wire.begin(); #if ARDUINO >= 157 Wire.setClock(400000UL); // Set I2C frequency to 400kHz #else TWBR = ((F_CPU / 400000UL) - 16) / 2; // Set I2C frequency to 400kHz #endif while (i2cRead(0x75, i2cBuffer, 1)); if (i2cBuffer[0] != 0x68) { // Read "WHO_AM_I" register Serial.print(F("Error reading sensor")); buzzer::Set(); while (1); // Halt } while (i2cWrite(0x6B, 0x80, true)); // Reset device, this resets all internal registers to their default values do { while (i2cRead(0x6B, i2cBuffer, 1)); } while (i2cBuffer[0] & 0x80); // Wait for the bit to clear delay(5); while (i2cWrite(0x6B, 0x09, true)); // PLL with X axis gyroscope reference, disable temperature sensor and disable sleep mode #if 1 i2cBuffer[0] = 1; // Set the sample rate to 500Hz - 1kHz/(1+1) = 500Hz i2cBuffer[1] = 0x03; // Disable FSYNC and set 44 Hz Acc filtering, 42 Hz Gyro filtering, 1 KHz sampling #else i2cBuffer[0] = 15; // Set the sample rate to 500Hz - 8kHz/(15+1) = 500Hz i2cBuffer[1] = 0x00; // Disable FSYNC and set 260 Hz Acc filtering, 256 Hz Gyro filtering, 8 KHz sampling #endif i2cBuffer[2] = 0x00; // Set Gyro Full Scale Range to ±250deg/s i2cBuffer[3] = 0x00; // Set Accelerometer Full Scale Range to ±2g while (i2cWrite(0x19, i2cBuffer, 4, true)); // Write to all four registers at once delay(100); // Wait for the sensor to get ready /* Set Kalman and gyro starting angle */ while (i2cRead(0x3D, i2cBuffer, 4)); int16_t accY = ((i2cBuffer[0] << 8) | i2cBuffer[1]); int16_t accZ = ((i2cBuffer[2] << 8) | i2cBuffer[3]); // atan2 outputs the value of -π to π (radians) - see http://en.wikipedia.org/wiki/Atan2 // We then convert it to 0 to 2π and then from radians to degrees accAngle = (atan2((float)accY - cfg.accYzero, (float)accZ - cfg.accZzero) + PI) * RAD_TO_DEG; kalman.setAngle(accAngle); // Set starting angle pitch = accAngle; gyroAngle = accAngle; /* Calibrate gyro zero value */ while (calibrateGyro()); // Run again if the robot is moved while calibrating LED::SetDirWrite(); // Set LED pin to output stopAndReset(); // Turn off motors and reset different values #ifdef ENABLE_TOOLS printMenu(); #endif /* Beep to indicate that it is now ready */ buzzer::Set(); delay(100); buzzer::Clear(); /* Setup timing */ kalmanTimer = micros(); pidTimer = kalmanTimer; imuTimer = millis(); encoderTimer = imuTimer; reportTimer = imuTimer; ledTimer = imuTimer; blinkTimer = imuTimer; } void loop() { if (!leftDiag::IsSet() || !rightDiag::IsSet()) { // Motor driver will pull these low on error buzzer::Set(); stopMotor(left); stopMotor(right); while (1); } #if defined(ENABLE_WII) || defined(ENABLE_PS4) // We have to read much more often from the Wiimote and PS4 controller to decrease latency bool readUSB = false; #ifdef ENABLE_WII if (Wii.wiimoteConnected) readUSB = true; #endif #ifdef ENABLE_PS4 if (PS4.connected()) readUSB = true; #endif if (readUSB) Usb.Task(); #endif /* Calculate pitch */ while (i2cRead(0x3D, i2cBuffer, 8)); int16_t accY = ((i2cBuffer[0] << 8) | i2cBuffer[1]); int16_t accZ = ((i2cBuffer[2] << 8) | i2cBuffer[3]); int16_t gyroX = ((i2cBuffer[6] << 8) | i2cBuffer[7]); // atan2 outputs the value of -π to π (radians) - see http://en.wikipedia.org/wiki/Atan2 // We then convert it to 0 to 2π and then from radians to degrees accAngle = (atan2((float)accY - cfg.accYzero, (float)accZ - cfg.accZzero) + PI) * RAD_TO_DEG; uint32_t timer = micros(); // This fixes the 0-360 transition problem when the accelerometer angle jumps between 0 and 360 degrees if ((accAngle < 90 && pitch > 270) || (accAngle > 270 && pitch < 90)) { kalman.setAngle(accAngle); pitch = accAngle; gyroAngle = accAngle; } else { float gyroRate = ((float)gyroX - gyroXzero) / 131.0f; // Convert to deg/s float dt = (float)(timer - kalmanTimer) / 1000000.0f; gyroAngle += gyroRate * dt; // Gyro angle is only used for debugging if (gyroAngle < 0 || gyroAngle > 360) gyroAngle = pitch; // Reset the gyro angle when it has drifted too much pitch = kalman.getAngle(accAngle, gyroRate, dt); // Calculate the angle using a Kalman filter } kalmanTimer = timer; //Serial.print(accAngle);Serial.print('\t');Serial.print(gyroAngle);Serial.print('\t');Serial.println(pitch); #if defined(ENABLE_WII) || defined(ENABLE_PS4) // We have to read much more often from the Wiimote and PS4 controller to decrease latency if (readUSB) Usb.Task(); #endif /* Drive motors */ timer = micros(); // If the robot is laying down, it has to be put in a vertical position before it starts balancing // If it's already balancing it has to be ±45 degrees before it stops trying to balance if ((layingDown && (pitch < cfg.targetAngle - 10 || pitch > cfg.targetAngle + 10)) || (!layingDown && (pitch < cfg.targetAngle - 45 || pitch > cfg.targetAngle + 45))) { layingDown = true; // The robot is in a unsolvable position, so turn off both motors and wait until it's vertical again stopAndReset(); } else { layingDown = false; // It's no longer laying down updatePID(cfg.targetAngle, targetOffset, turningOffset, (float)(timer - pidTimer) / 1000000.0f); } pidTimer = timer; /* Update encoders */ timer = millis(); if (timer - encoderTimer >= 100) { // Update encoder values every 100ms encoderTimer = timer; int32_t wheelPosition = getWheelsPosition(); wheelVelocity = wheelPosition - lastWheelPosition; lastWheelPosition = wheelPosition; //Serial.print(wheelPosition);Serial.print('\t');Serial.print(targetPosition);Serial.print('\t');Serial.println(wheelVelocity); if (abs(wheelVelocity) <= 40 && !stopped) { // Set new targetPosition if braking targetPosition = wheelPosition; stopped = true; } batteryCounter++; if (batteryCounter >= 10) { // Measure battery every 1s batteryCounter = 0; batteryVoltage = (float)analogRead(VBAT) / 63.050847458f; // VBAT is connected to analog input 5 which is not broken out. This is then connected to a 47k-12k voltage divider - 1023.0/(3.3/(12.0/(12.0+47.0))) = 63.050847458 if (batteryVoltage < 10.2 && batteryVoltage > 5) // Equal to 3.4V per cell - don't turn on if it's below 5V, this means that no battery is connected buzzer::Set(); else buzzer::Clear(); } } /* Read the Bluetooth dongle and send PID and IMU values */ #if defined(ENABLE_TOOLS) || defined(ENABLE_SPEKTRUM) checkSerialData(); #endif #if defined(ENABLE_USB) || defined(ENABLE_SPEKTRUM) readUsb(); #endif #if defined(ENABLE_TOOLS) || defined(ENABLE_SPP) printValues(); #endif #ifdef ENABLE_BTD if (Btd.isReady()) { timer = millis(); if ((Btd.watingForConnection && timer - blinkTimer > 1000) || (!Btd.watingForConnection && timer - blinkTimer > 100)) { blinkTimer = timer; LED::Toggle(); // Used to blink the built in LED, starts blinking faster upon an incoming Bluetooth request } } else LED::Clear(); // This will turn it off #endif }