FollowDigitalPosition.cpp

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/*
 * Title: FollowDigitalPosition
 *
 * Objective:
 *    This example demonstrates control of the ClearPath-MCPV operational mode
 *    Follow Digital Position Command, Unipolar PWM Command.
 *
 * Description:
 *    This example enables and then moves a ClearPath motor between various
 *    positions within a range defined in the MSP software based on the state
 *    of an analog input. During operation, various move statuses are written
 *    to the USB serial port.
 *    To achieve better positioning resolution (i.e. more commandable positions),  
 *    consider using the ClearPath operational modes "Pulse Burst Positioning"
 *    or "Move Incremental Distance" instead.
 *
 * Requirements:
 * 1. A ClearPath motor must be connected to Connector M-0.
 * 2. The connected ClearPath motor must be configured through the MSP software
 *    for Follow Digital Position Command, Unipolar PWM Command mode (In MSP
 *    select Mode>>Position>>Follow Digital Position Command, then with
 *    "Unipolar PWM Command" selected hit the OK button).
 * 3. The ClearPath motor must be set to use the HLFB mode "ASG-Position
 *    w/Measured Torque" with a PWM carrier frequency of 482 Hz through the MSP
 *    software (select Advanced>>High Level Feedback [Mode]... then choose
 *    "ASG-Position w/Measured Torque" from the dropdown, make sure that 482 Hz
 *    is selected in the "PWM Carrier Frequency" dropdown, and hit the OK
 *    button).
 * 4. The ClearPath must have defined positions for 0% and 100% PWM (On the
 *    main MSP window check the "Position Range Setup (cnts)" box and fill in
 *    the two text boxes labeled "Posn at 0% PWM" and "Posn at 100% PWM").
 *    Change the "PositionZeroPWM" and "PositionMaxPWM" variables in the example
 *    below to match.
 * 5. Homing must be configured in the MSP software for your mechanical
 *    system (e.g. homing direction, torque limit, etc.). This example does
 *    not use the ClearPath's Input A as a homing sensor, although that may
 *    be configured in this mode through MSP.
 * 6. An analog input source (0-10V) connected to Connector A-9 to control motor 
 *    position.
 * 7. (Optional) An input source, such as a switch, connected to DI-6 to control
 *    the Command Lock or Home Sensor (configured in MSP).
 *
 * Links:
 * ** ClearCore Documentation: https://teknic-inc.github.io/ClearCore-library/
 * ** ClearCore Manual: https://www.teknic.com/files/downloads/clearcore_user_manual.pdf
 * ** ClearPath Manual (DC Power): https://www.teknic.com/files/downloads/clearpath_user_manual.pdf
 * ** ClearPath Manual (AC Power): https://www.teknic.com/files/downloads/ac_clearpath-mc-sd_manual.pdf
 * ** ClearPath Mode Informational Video: https://www.teknic.com/watch-video/#OpMode12
 *
 * 
 * Copyright (c) 2020 Teknic Inc. This work is free to use, copy and distribute under the terms of
 * the standard MIT permissive software license which can be found at https://opensource.org/licenses/MIT
 */
 
#include "ClearCore.h"
 
// Defines the motor's connector
#define motor ConnectorM0
 
// Defines the command lock sensor connector
#define LockSensor ConnectorDI6
 
// Defines the analog input to control commanded position
#define AnalogSensor ConnectorA9
 
// Select the baud rate to match the target device.
#define baudRate 9600
 
// Specify which serial to use: ConnectorUsb, ConnectorCOM0, or ConnectorCOM1.
#define SerialPort ConnectorUsb
 
// This example has built-in functionality to automatically clear motor faults. 
//  Any uncleared fault will cancel and disallow motion.
// WARNING: enabling automatic fault handling will clear faults immediately when 
//  encountered and return a motor to a state in which motion is allowed. Before 
//  enabling this functionality, be sure to understand this behavior and ensure 
//  your system will not enter an unsafe state. 
// To enable automatic fault handling, #define HANDLE_MOTOR_FAULTS (1)
// To disable automatic fault handling, #define HANDLE_MOTOR_FAULTS (0)
#define HANDLE_MOTOR_FAULTS (0)
 
// Declares user-defined helper functions.
// The definition/implementations of these functions are at the bottom of the sketch.
double positionZeroPWM = 0;
double positionMaxPWM = 10000;
void HandleMotorFaults();
 
// Declares our user-defined functions, which are used to pass the Command Lock
// sensor state and send position commands to the motor. The implementations of
// these functions are at the bottom of the sketch.
void LockSensorCallback();
bool CommandPosition(int32_t commandedPosition);
 
int main() {
    // Set up an analog sensor to control commanded position.
    AnalogSensor.Mode(Connector::INPUT_ANALOG);
 
    // Sets all motor connectors to the correct mode for Follow Digital
    // Position mode.
    MotorMgr.MotorModeSet(MotorManager::MOTOR_ALL,
                          Connector::CPM_MODE_A_DIRECT_B_PWM);
 
    // Set the motor's HLFB mode to bipolar PWM
    motor.HlfbMode(MotorDriver::HLFB_MODE_HAS_BIPOLAR_PWM);
    // Set the HFLB carrier frequency to 482 Hz
    motor.HlfbCarrier(MotorDriver::HLFB_CARRIER_482_HZ);
 
    // This section attaches the interrupt callback to the locking sensor pin,
    // set to trigger on any change of sensor state.
    LockSensor.Mode(Connector::INPUT_DIGITAL);
    LockSensor.InterruptHandlerSet(LockSensorCallback, InputManager::CHANGE, true);
    // Set input A to match the initial state of the sensor.
    motor.MotorInAState(LockSensor.State());
 
    // Sets up serial communication and waits up to 5 seconds for a port to open.
    // Serial communication is not required for this example to run.
    SerialPort.Mode(Connector::USB_CDC);
    SerialPort.Speed(baudRate);
    uint32_t timeout = 5000;
    uint32_t startTime = Milliseconds();
    SerialPort.PortOpen();
    while (!SerialPort && Milliseconds() - startTime < timeout) {
        continue;
    }
 
    // Enables the motor; homing will begin automatically if applicable
    motor.EnableRequest(true);
    SerialPort.SendLine("Motor Enabled");
 
    // Waits for HLFB to assert (waits for homing to complete if applicable)
    SerialPort.SendLine("Waiting for HLFB...");
    while (motor.HlfbState() != MotorDriver::HLFB_ASSERTED &&
            !motor.StatusReg().bit.MotorInFault) {
        continue;
    }
    // Check if a motor faulted during enabling
    // Clear fault if configured to do so 
    if (motor.StatusReg().bit.MotorInFault) {
        SerialPort.SendLine("Motor fault detected.");       
        if(HANDLE_MOTOR_FAULTS){
            HandleMotorFaults();
        } else {
            SerialPort.SendLine("Enable automatic fault handling by setting HANDLE_MOTOR_FAULTS to 1.");
        }
        SerialPort.SendLine("Enabling may not have completed as expected. Proceed with caution.");      
        SerialPort.SendLine();
    } else {
        SerialPort.SendLine("Motor Ready"); 
    }
 
    while (true) {
        // Read the voltage on the analog sensor (0-10V).
        float analogVoltage = AnalogSensor.AnalogVoltage();
        // Convert the voltage measured to a position within the valid range.
        int32_t commandedPosition =
            static_cast<int32_t>(round(analogVoltage / 10 * positionMaxPWM));
        CommandPosition(commandedPosition);    // See below for the detailed function definition.
    }
}
 
/*------------------------------------------------------------------------------
 * CommandPosition
 *
 *    Move to position number commandedPosition (counts in MSP)
 *    Prints the move status to the USB serial port
 *    Returns whether the command has been updated.
 *
 * Parameters:
 *    int commandedPosition  - The position, in counts, to command
 *
 */
bool CommandPosition(int32_t commandedPosition) {
    if (abs(commandedPosition) > abs(positionMaxPWM) ||
        abs(commandedPosition) < abs(positionZeroPWM)) {
        SerialPort.SendLine("Move rejected, invalid position requested");
        return false;
    }
 
    // Check if a motor fault is currently preventing motion
    // Clear fault if configured to do so 
    if (motor.StatusReg().bit.MotorInFault) {
        if(HANDLE_MOTOR_FAULTS){
            SerialPort.SendLine("Motor fault detected. Move canceled.");
            HandleMotorFaults();
        } else {
            SerialPort.SendLine("Motor fault detected. Move canceled. Enable automatic fault handling by setting HANDLE_MOTOR_FAULTS to 1.");
        }
        return false;
    }
 
    SerialPort.Send("Moving to position: ");
    SerialPort.SendLine(commandedPosition);
 
    // Find the scaling factor of our position range mapped to the PWM duty
    // cycle range (255 is the max duty cycle).
    double scaleFactor = 255 / abs(positionMaxPWM - positionZeroPWM);
 
    // Scale the position command to our duty cycle range.
    uint8_t dutyRequest = abs(commandedPosition - positionZeroPWM) * scaleFactor;
 
    // Command the move.
    motor.MotorInBDuty(dutyRequest);
 
    return true;
}
//------------------------------------------------------------------------------
 
/*------------------------------------------------------------------------------
 * LockSensorCallback
 *
 *    Reads the state of the locking sensor and passes the state to the motor.
 *
 * Parameters:
 *    None
 *
 * Returns: None
 */
void LockSensorCallback() {
    // A 1 ms delay is required in order to pass the correct filtered sensor
    // state.
    Delay_ms(1);
    motor.MotorInAState(LockSensor.State());
}
//------------------------------------------------------------------------------
 
/*------------------------------------------------------------------------------
 * HandleMotorFaults
 *
 *    Clears motor faults by cycling enable to the motor.
 *    Assumes motor is in fault 
 *      (this function is called when motor.StatusReg.MotorInFault == true)
 *
 * Parameters:
 *    requires "motor" to be defined as a ClearCore motor connector
 *
 * Returns: 
 *    none
 */
 void HandleMotorFaults(){
    SerialPort.SendLine("Handling fault: clearing faults by cycling enable signal to motor.");
    motor.EnableRequest(false);
    Delay_ms(10);
    motor.EnableRequest(true);
    Delay_ms(100);
 }
//------------------------------------------------------------------------------