ardupilot/libraries/AP_Motors/AP_MotorsMatrix.cpp

/*
	AP_MotorsMatrix.cpp - ArduCopter motors library
	Code by RandyMackay. DIYDrones.com

	This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.
*/

#include "AP_MotorsMatrix.h"

// Init
void AP_MotorsMatrix::Init()
{
	int8_t i;

	// setup the motors
	setup_motors();

	// double check that opposite motor definitions are ok
	for( i=0; i<AP_MOTORS_MAX_NUM_MOTORS; i++ ) {
		if( opposite_motor[i] <= 0 || opposite_motor[i] >= AP_MOTORS_MAX_NUM_MOTORS || !motor_enabled[opposite_motor[i]] )
			opposite_motor[i] = AP_MOTORS_MATRIX_MOTOR_UNDEFINED;
	}

	// enable fast channels or instant pwm
	set_update_rate(_speed_hz);
}

// set update rate to motors - a value in hertz or AP_MOTORS_SPEED_INSTANT_PWM for instant pwm
void AP_MotorsMatrix::set_update_rate( uint16_t speed_hz )
{
	uint32_t fast_channel_mask = 0;
	int8_t i;

	// record requested speed
	_speed_hz = speed_hz;

	// initialise instant_pwm booleans.  they will be set again below
	instant_pwm_force01 = false;
	instant_pwm_force23 = false;
	instant_pwm_force67 = false;

	// check each enabled motor
	for( i=0; i<AP_MOTORS_MAX_NUM_MOTORS; i++ ) {
		if( motor_enabled[i] ) {
			// set-up fast channel mask
			fast_channel_mask |= _BV(_motor_to_channel_map[i]);	// add to fast channel map

			// and instant pwm
			if( _motor_to_channel_map[i] == 0 || _motor_to_channel_map[i] == 1 )
				instant_pwm_force01 = true;
			if( _motor_to_channel_map[i] == 2 || _motor_to_channel_map[i] == 3 )
				instant_pwm_force23 = true;
			if( _motor_to_channel_map[i] == 6 || _motor_to_channel_map[i] == 7 )
				instant_pwm_force67 = true;
		}
	}

	// enable fast channels
	if( _speed_hz != AP_MOTORS_SPEED_INSTANT_PWM ) {
		_rc->SetFastOutputChannels(fast_channel_mask, _speed_hz);
	}
}

// set frame orientation (normally + or X)
void AP_MotorsMatrix::set_frame_orientation( uint8_t new_orientation )
{
	// return if nothing has changed
	if( new_orientation == _frame_orientation ) {
		return;
	}

	// call parent
	AP_Motors::set_frame_orientation( new_orientation );

	// setup the motors
	setup_motors();

	// enable fast channels or instant pwm
	set_update_rate(_speed_hz);
}

// enable - starts allowing signals to be sent to motors
void AP_MotorsMatrix::enable()
{
	int8_t i;

	// enable output channels
	for( i=0; i<AP_MOTORS_MAX_NUM_MOTORS; i++ ) {
		if( motor_enabled[i] ) {
			_rc->enable_out(_motor_to_channel_map[i]);
		}
	}
}

// output_min - sends minimum values out to the motors
void AP_MotorsMatrix::output_min()
{
	int8_t i;

	// fill the motor_out[] array for HIL use and send minimum value to each motor
	for( i=0; i<AP_MOTORS_MAX_NUM_MOTORS; i++ ) {
		if( motor_enabled[i] ) {
			motor_out[i] = _rc_throttle->radio_min;
			_rc->OutputCh(_motor_to_channel_map[i], motor_out[i]);
		}
	}

	// Force output if instant pwm
	if( _speed_hz == AP_MOTORS_SPEED_INSTANT_PWM ) {
		if( instant_pwm_force01 )
			_rc->Force_Out0_Out1();
		if( instant_pwm_force23 )
			_rc->Force_Out2_Out3();
		if( instant_pwm_force67 )
			_rc->Force_Out6_Out7();
	}
}

// output_armed - sends commands to the motors
void AP_MotorsMatrix::output_armed()
{
	int8_t i;
	int16_t out_min = _rc_throttle->radio_min;
	int16_t out_max = _rc_throttle->radio_max;
	int16_t yaw_contribution = 0;

	// Throttle is 0 to 1000 only
	_rc_throttle->servo_out = constrain(_rc_throttle->servo_out, 0, _max_throttle);

	if(_rc_throttle->servo_out > 0)
		out_min = _rc_throttle->radio_min + _min_throttle;

	// capture desired roll, pitch, yaw and throttle from receiver
	_rc_roll->calc_pwm();
	_rc_pitch->calc_pwm();
	_rc_throttle->calc_pwm();
	_rc_yaw->calc_pwm();

	// mix roll, pitch, yaw, throttle into output for each motor
	for( i=0; i<AP_MOTORS_MAX_NUM_MOTORS; i++ ) {
		if( motor_enabled[i] ) {
			yaw_contribution = _rc_yaw->pwm_out*_yaw_factor[i];
			if (yaw_contribution > 0 ){
				yaw_contribution *= 0.7;
			}else{
				yaw_contribution *= 1.42;
			}
			motor_out[i] = _rc_throttle->radio_out +
							_rc_roll->pwm_out * _roll_factor[i] +
							_rc_pitch->pwm_out * _pitch_factor[i] +
							yaw_contribution;
		}
	}

	// stability patch
	for( i=0; i<AP_MOTORS_MAX_NUM_MOTORS; i++ ) {
		if( motor_enabled[i] && motor_out[i] > out_max ) {
			if( opposite_motor[i] != AP_MOTORS_MATRIX_MOTOR_UNDEFINED ) {
				motor_out[opposite_motor[i]] -= motor_out[i] - out_max;
			}
			motor_out[i] = out_max;
		}
	}

	// ensure motors are not below the minimum
	for( i=0; i<AP_MOTORS_MAX_NUM_MOTORS; i++ ) {
		if( motor_enabled[i] ) {
			motor_out[i] = max(motor_out[i], out_min);
		}
	}

	#if CUT_MOTORS == ENABLED
	// if we are not sending a throttle output, we cut the motors
	if(_rc_throttle->servo_out == 0){
		for( i=0; i<AP_MOTORS_MAX_NUM_MOTORS; i++ ) {
			if( motor_enabled[i] ) {
				motor_out[i]	= _rc_throttle->radio_min;
			}
		}
	}
	#endif

	// send output to each motor
	for( i=0; i<AP_MOTORS_MAX_NUM_MOTORS; i++ ) {
		if( motor_enabled[i] ) {
			_rc->OutputCh(_motor_to_channel_map[i], motor_out[i]);
		}
	}

	// InstantPWM
	if( _speed_hz == AP_MOTORS_SPEED_INSTANT_PWM ) {
		if( instant_pwm_force01 )
			_rc->Force_Out0_Out1();
		if( instant_pwm_force23 )
			_rc->Force_Out2_Out3();
		if( instant_pwm_force67 )
			_rc->Force_Out6_Out7();
	}
}

// output_disarmed - sends commands to the motors
void AP_MotorsMatrix::output_disarmed()
{
	if(_rc_throttle->control_in > 0){
		// we have pushed up the throttle
		// remove safety for auto pilot
		_auto_armed = true;
	}

	// Send minimum values to all motors
	output_min();
}

// output_disarmed - sends commands to the motors
void AP_MotorsMatrix::output_test()
{
	int8_t min_order, max_order;
	int8_t i,j;

	// find min and max orders
	min_order = test_order[0];
	max_order = test_order[0];
	for(i=1; i<AP_MOTORS_MAX_NUM_MOTORS; i++ ) {
		if( test_order[i] < min_order )
			min_order = test_order[i];
		if( test_order[i] > max_order )
			max_order = test_order[i];
	}

	// shut down all motors
	output_min();

	// first delay is longer
	delay(4000);
	
	// loop through all the possible orders spinning any motors that match that description
	for( i=min_order; i<=max_order; i++ ) {
		for( j=0; j<AP_MOTORS_MAX_NUM_MOTORS; j++ ) {
			if( motor_enabled[j] && test_order[j] == i ) {
				// turn on this motor and wait 1/3rd of a second
				_rc->OutputCh(_motor_to_channel_map[j], _rc_throttle->radio_min + 100);
				delay(300);
				_rc->OutputCh(_motor_to_channel_map[j], _rc_throttle->radio_min);
				delay(2000);
			}
		}
	}

	// shut down all motors
	output_min();
}

// add_motor
void AP_MotorsMatrix::add_motor_raw(int8_t motor_num, float roll_fac, float pitch_fac, float yaw_fac, int8_t opposite_motor_num, int8_t testing_order)
{
	// ensure valid motor number is provided
	if( motor_num >= 0 && motor_num < AP_MOTORS_MAX_NUM_MOTORS ) {
	
		// increment number of motors if this motor is being newly motor_enabled
		if( !motor_enabled[motor_num] ) {
			motor_enabled[motor_num] = true;
			_num_motors++;
		}

		// set roll, pitch, thottle factors and opposite motor (for stability patch)
		_roll_factor[motor_num] = roll_fac;
		_pitch_factor[motor_num] = pitch_fac;
		_yaw_factor[motor_num] = yaw_fac;

		// set opposite motor after checking it's somewhat valid
		if( opposite_motor_num == AP_MOTORS_MATRIX_MOTOR_UNDEFINED || (opposite_motor_num >=0 && opposite_motor_num < AP_MOTORS_MAX_NUM_MOTORS) ) {
			opposite_motor[motor_num] = opposite_motor_num;
		}else{
			opposite_motor[motor_num] = AP_MOTORS_MATRIX_MOTOR_UNDEFINED;
		}

		// set order that motor appears in test
		if( testing_order == AP_MOTORS_MATRIX_ORDER_UNDEFINED ) {
			test_order[motor_num] = motor_num;
		}else{
			test_order[motor_num] = testing_order;
		}
	}
}

// add_motor using just position and prop direction
void AP_MotorsMatrix::add_motor(int8_t motor_num, float angle_degrees, int8_t direction, int8_t opposite_motor_num, int8_t testing_order)
{
	// call raw motor set-up method
	add_motor_raw(
		motor_num,
		cos(radians(angle_degrees + 90)),	// roll factor
		cos(radians(angle_degrees)),		// pitch factor
		(float)direction,					// yaw factor
		opposite_motor_num,
		testing_order);

}

// remove_motor - disabled motor and clears all roll, pitch, throttle factors for this motor
void AP_MotorsMatrix::remove_motor(int8_t motor_num)
{
	int8_t i;

	// ensure valid motor number is provided
	if( motor_num >= 0 && motor_num <= AP_MOTORS_MAX_NUM_MOTORS ) {

		// if the motor was enabled decrement the number of motors
		if( motor_enabled[motor_num] )
			_num_motors--;

		// disable the motor, set all factors to zero
		motor_enabled[motor_num] = false;
		_roll_factor[motor_num] = 0;
		_pitch_factor[motor_num] = 0;
		_yaw_factor[motor_num] = 0;
		opposite_motor[motor_num] = AP_MOTORS_MATRIX_MOTOR_UNDEFINED;
	}

	// if another motor has referred to this motor as it's opposite, remove that reference 
	for( i=0; i<AP_MOTORS_MAX_NUM_MOTORS; i++ ) {
		if( opposite_motor[i] == motor_num )
			opposite_motor[i] = AP_MOTORS_MATRIX_MOTOR_UNDEFINED;
	}
}

// remove_all_motors - removes all motor definitions
void AP_MotorsMatrix::remove_all_motors()
{
	for( int8_t i=0; i<AP_MOTORS_MAX_NUM_MOTORS; i++ ) {
		remove_motor(i);
	}
	_num_motors = 0;
}