ardupilot/ArduSub/motors.cpp

#include "Sub.h"

// enable_motor_output() - enable and output lowest possible value to motors
void Sub::enable_motor_output()
{
    motors.output_min();
}

// init_arm_motors - performs arming process including initialisation of barometer and gyros
//  returns false if arming failed because of pre-arm checks, arming checks or a gyro calibration failure
bool Sub::init_arm_motors(bool arming_from_gcs)
{
    static bool in_arm_motors = false;

    // exit immediately if already in this function
    if (in_arm_motors) {
        return false;
    }

    in_arm_motors = true;

    if (!arming.pre_arm_checks(true)) {
        AP_Notify::events.arming_failed = true;
        in_arm_motors = false;
        return false;
    }

    // let dataflash know that we're armed (it may open logs e.g.)
    DataFlash_Class::instance()->set_vehicle_armed(true);

    // disable cpu failsafe because initialising everything takes a while
    mainloop_failsafe_disable();

    // notify that arming will occur (we do this early to give plenty of warning)
    AP_Notify::flags.armed = true;
    // call update_notify a few times to ensure the message gets out
    for (uint8_t i=0; i<=10; i++) {
        update_notify();
    }

#if CONFIG_HAL_BOARD == HAL_BOARD_SITL
    gcs().send_text(MAV_SEVERITY_INFO, "Arming motors");
#endif

    initial_armed_bearing = ahrs.yaw_sensor;

    if (ap.home_state == HOME_UNSET) {
        // Reset EKF altitude if home hasn't been set yet (we use EKF altitude as substitute for alt above home)

        // Always use absolute altitude for ROV
        // ahrs.resetHeightDatum();
        // Log_Write_Event(DATA_EKF_ALT_RESET);
    } else if (ap.home_state == HOME_SET_NOT_LOCKED) {
        // Reset home position if it has already been set before (but not locked)
        set_home_to_current_location(false);
    }
	
    // enable gps velocity based centrefugal force compensation
    ahrs.set_correct_centrifugal(true);
    hal.util->set_soft_armed(true);

    // enable output to motors
    enable_motor_output();

    // finally actually arm the motors
    motors.armed(true);

    // log arming to dataflash
    Log_Write_Event(DATA_ARMED);

    // log flight mode in case it was changed while vehicle was disarmed
    DataFlash.Log_Write_Mode(control_mode, control_mode_reason);

    // reenable failsafe
    mainloop_failsafe_enable();

    // perf monitor ignores delay due to arming
    perf_info.ignore_this_loop();

    // flag exiting this function
    in_arm_motors = false;

    // return success
    return true;
}

// init_disarm_motors - disarm motors
void Sub::init_disarm_motors()
{
    // return immediately if we are already disarmed
    if (!motors.armed()) {
        return;
    }

#if CONFIG_HAL_BOARD == HAL_BOARD_SITL
    gcs().send_text(MAV_SEVERITY_INFO, "Disarming motors");
#endif

    // save compass offsets learned by the EKF if enabled
    if (ahrs.use_compass() && compass.get_learn_type() == Compass::LEARN_EKF) {
        for (uint8_t i=0; i<COMPASS_MAX_INSTANCES; i++) {
            Vector3f magOffsets;
            if (ahrs.getMagOffsets(i, magOffsets)) {
                compass.set_and_save_offsets(i, magOffsets);
            }
        }
    }

    // log disarm to the dataflash
    Log_Write_Event(DATA_DISARMED);

    // send disarm command to motors
    motors.armed(false);

    // reset the mission
    mission.reset();

    DataFlash_Class::instance()->set_vehicle_armed(false);

    // disable gps velocity based centrefugal force compensation
    ahrs.set_correct_centrifugal(false);
    hal.util->set_soft_armed(false);

    // clear input holds
    clear_input_hold();
}

// motors_output - send output to motors library which will adjust and send to ESCs and servos
void Sub::motors_output()
{
    // check if we are performing the motor test
    if (ap.motor_test) {
        return; // Placeholder
    }
    motors.set_interlock(true);
    motors.output();
}

// translate wpnav roll/pitch outputs to lateral/forward
void Sub::translate_wpnav_rp(float &lateral_out, float &forward_out)
{
    // get roll and pitch targets in centidegrees
    int32_t lateral = wp_nav.get_roll();
    int32_t forward = -wp_nav.get_pitch(); // output is reversed

    // constrain target forward/lateral values
    // The outputs of wp_nav.get_roll and get_pitch should already be constrained to these values
    lateral = constrain_int16(lateral, -aparm.angle_max, aparm.angle_max);
    forward = constrain_int16(forward, -aparm.angle_max, aparm.angle_max);

    // Normalize
    lateral_out = (float)lateral/(float)aparm.angle_max;
    forward_out = (float)forward/(float)aparm.angle_max;
}

// translate wpnav roll/pitch outputs to lateral/forward
void Sub::translate_circle_nav_rp(float &lateral_out, float &forward_out)
{
    // get roll and pitch targets in centidegrees
    int32_t lateral = circle_nav.get_roll();
    int32_t forward = -circle_nav.get_pitch(); // output is reversed

    // constrain target forward/lateral values
    lateral = constrain_int16(lateral, -aparm.angle_max, aparm.angle_max);
    forward = constrain_int16(forward, -aparm.angle_max, aparm.angle_max);

    // Normalize
    lateral_out = (float)lateral/(float)aparm.angle_max;
    forward_out = (float)forward/(float)aparm.angle_max;
}

// translate pos_control roll/pitch outputs to lateral/forward
void Sub::translate_pos_control_rp(float &lateral_out, float &forward_out)
{
    // get roll and pitch targets in centidegrees
    int32_t lateral = pos_control.get_roll();
    int32_t forward = -pos_control.get_pitch(); // output is reversed

    // constrain target forward/lateral values
    lateral = constrain_int16(lateral, -aparm.angle_max, aparm.angle_max);
    forward = constrain_int16(forward, -aparm.angle_max, aparm.angle_max);

    // Normalize
    lateral_out = (float)lateral/(float)aparm.angle_max;
    forward_out = (float)forward/(float)aparm.angle_max;
}