ardupilot/libraries/AP_Motors/AP_MotorsMulticopter.cpp

739 lines
29 KiB
C++

/*
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/*
* AP_MotorsMulticopter.cpp - ArduCopter multicopter motors library
* Code by Randy Mackay and Robert Lefebvre. DIYDrones.com
*
*/
#include "AP_MotorsMulticopter.h"
#include <AP_HAL/AP_HAL.h>
#include <AP_BattMonitor/AP_BattMonitor.h>
extern const AP_HAL::HAL& hal;
// parameters for the motor class
const AP_Param::GroupInfo AP_MotorsMulticopter::var_info[] = {
// 0 was used by TB_RATIO
// 1,2,3 were used by throttle curve
// 5 was SPIN_ARMED
// @Param: YAW_HEADROOM
// @DisplayName: Matrix Yaw Min
// @Description: Yaw control is given at least this pwm in microseconds range
// @Range: 0 500
// @Units: PWM
// @User: Advanced
AP_GROUPINFO("YAW_HEADROOM", 6, AP_MotorsMulticopter, _yaw_headroom, AP_MOTORS_YAW_HEADROOM_DEFAULT),
// 7 was THR_LOW_CMP
// @Param: THST_EXPO
// @DisplayName: Thrust Curve Expo
// @Description: Motor thrust curve exponent (from 0 for linear to 1.0 for second order curve)
// @Range: 0.25 0.8
// @User: Advanced
AP_GROUPINFO("THST_EXPO", 8, AP_MotorsMulticopter, _thrust_curve_expo, AP_MOTORS_THST_EXPO_DEFAULT),
// @Param: SPIN_MAX
// @DisplayName: Motor Spin maximum
// @Description: Point at which the thrust saturates expressed as a number from 0 to 1 in the entire output range
// @Values: 0.9:Low, 0.95:Default, 1.0:High
// @User: Advanced
AP_GROUPINFO("SPIN_MAX", 9, AP_MotorsMulticopter, _spin_max, AP_MOTORS_SPIN_MAX_DEFAULT),
// @Param: BAT_VOLT_MAX
// @DisplayName: Battery voltage compensation maximum voltage
// @Description: Battery voltage compensation maximum voltage (voltage above this will have no additional scaling effect on thrust). Recommend 4.4 * cell count, 0 = Disabled
// @Range: 6 35
// @Units: V
// @User: Advanced
AP_GROUPINFO("BAT_VOLT_MAX", 10, AP_MotorsMulticopter, _batt_voltage_max, AP_MOTORS_BAT_VOLT_MAX_DEFAULT),
// @Param: BAT_VOLT_MIN
// @DisplayName: Battery voltage compensation minimum voltage
// @Description: Battery voltage compensation minimum voltage (voltage below this will have no additional scaling effect on thrust). Recommend 3.5 * cell count, 0 = Disabled
// @Range: 6 35
// @Units: V
// @User: Advanced
AP_GROUPINFO("BAT_VOLT_MIN", 11, AP_MotorsMulticopter, _batt_voltage_min, AP_MOTORS_BAT_VOLT_MIN_DEFAULT),
// @Param: BAT_CURR_MAX
// @DisplayName: Motor Current Max
// @Description: Maximum current over which maximum throttle is limited (0 = Disabled)
// @Range: 0 200
// @Units: A
// @User: Advanced
AP_GROUPINFO("BAT_CURR_MAX", 12, AP_MotorsMulticopter, _batt_current_max, AP_MOTORS_BAT_CURR_MAX_DEFAULT),
// 13, 14 were used by THR_MIX_MIN, THR_MIX_MAX
// @Param: PWM_TYPE
// @DisplayName: Output PWM type
// @Description: This selects the output PWM type, allowing for normal PWM continuous output, OneShot, brushed or DShot motor output
// @Values: 0:Normal,1:OneShot,2:OneShot125,3:Brushed,4:DShot150,5:DShot300,6:DShot600,7:DShot1200
// @User: Advanced
// @RebootRequired: True
AP_GROUPINFO("PWM_TYPE", 15, AP_MotorsMulticopter, _pwm_type, PWM_TYPE_NORMAL),
// @Param: PWM_MIN
// @DisplayName: PWM output miniumum
// @Description: This sets the min PWM output value in microseconds that will ever be output to the motors, 0 = use input RC3_MIN
// @Units: PWM
// @Range: 0 2000
// @User: Advanced
AP_GROUPINFO("PWM_MIN", 16, AP_MotorsMulticopter, _pwm_min, 0),
// @Param: PWM_MAX
// @DisplayName: PWM output maximum
// @Description: This sets the max PWM value in microseconds that will ever be output to the motors, 0 = use input RC3_MAX
// @Units: PWM
// @Range: 0 2000
// @User: Advanced
AP_GROUPINFO("PWM_MAX", 17, AP_MotorsMulticopter, _pwm_max, 0),
// @Param: SPIN_MIN
// @DisplayName: Motor Spin minimum
// @Description: Point at which the thrust starts expressed as a number from 0 to 1 in the entire output range. Should be higher than MOT_SPIN_ARM.
// @Values: 0.0:Low, 0.15:Default, 0.3:High
// @User: Advanced
AP_GROUPINFO("SPIN_MIN", 18, AP_MotorsMulticopter, _spin_min, AP_MOTORS_SPIN_MIN_DEFAULT),
// @Param: SPIN_ARM
// @DisplayName: Motor Spin armed
// @Description: Point at which the motors start to spin expressed as a number from 0 to 1 in the entire output range. Should be lower than MOT_SPIN_MIN.
// @Values: 0.0:Low, 0.1:Default, 0.2:High
// @User: Advanced
AP_GROUPINFO("SPIN_ARM", 19, AP_MotorsMulticopter, _spin_arm, AP_MOTORS_SPIN_ARM_DEFAULT),
// @Param: BAT_CURR_TC
// @DisplayName: Motor Current Max Time Constant
// @Description: Time constant used to limit the maximum current
// @Range: 0 10
// @Units: s
// @User: Advanced
AP_GROUPINFO("BAT_CURR_TC", 20, AP_MotorsMulticopter, _batt_current_time_constant, AP_MOTORS_BAT_CURR_TC_DEFAULT),
// @Param: THST_HOVER
// @DisplayName: Thrust Hover Value
// @Description: Motor thrust needed to hover expressed as a number from 0 to 1
// @Range: 0.2 0.8
// @User: Advanced
AP_GROUPINFO("THST_HOVER", 21, AP_MotorsMulticopter, _throttle_hover, AP_MOTORS_THST_HOVER_DEFAULT),
// @Param: HOVER_LEARN
// @DisplayName: Hover Value Learning
// @Description: Enable/Disable automatic learning of hover throttle
// @Values{Copter}: 0:Disabled, 1:Learn, 2:LearnAndSave
// @Values{Sub}: 0:Disabled
// @Values{Plane}: 0:Disabled
// @User: Advanced
AP_GROUPINFO("HOVER_LEARN", 22, AP_MotorsMulticopter, _throttle_hover_learn, HOVER_LEARN_AND_SAVE),
// @Param: SAFE_DISARM
// @DisplayName: Motor PWM output disabled when disarmed
// @Description: Disables motor PWM output when disarmed
// @Values: 0:PWM enabled while disarmed, 1:PWM disabled while disarmed
// @User: Advanced
AP_GROUPINFO("SAFE_DISARM", 23, AP_MotorsMulticopter, _disarm_disable_pwm, 0),
// @Param: YAW_SV_ANGLE
// @DisplayName: Yaw Servo Max Lean Angle
// @Description: Yaw servo's maximum lean angle
// @Range: 5 80
// @Units: deg
// @Increment: 1
// @User: Standard
AP_GROUPINFO_FRAME("YAW_SV_ANGLE", 35, AP_MotorsMulticopter, _yaw_servo_angle_max_deg, 30, AP_PARAM_FRAME_TRICOPTER),
// @Param: SPOOL_TIME
// @DisplayName: Spool up time
// @Description: Time in seconds to spool up the motors from zero to min throttle.
// @Range: 0 2
// @Units: s
// @Increment: 0.1
// @User: Advanced
AP_GROUPINFO("SPOOL_TIME", 36, AP_MotorsMulticopter, _spool_up_time, AP_MOTORS_SPOOL_UP_TIME_DEFAULT),
// @Param: BOOST_SCALE
// @DisplayName: Motor boost scale
// @Description: Booster motor output scaling factor vs main throttle. The output to the BoostThrottle servo will be the main throttle times this scaling factor. A higher scaling factor will put more of the load on the booster motor. A value of 1 will set the BoostThrottle equal to the main throttle.
// @Range: 0 5
// @Increment: 0.1
// @User: Advanced
AP_GROUPINFO("BOOST_SCALE", 37, AP_MotorsMulticopter, _boost_scale, 0),
// 38 RESERVED for BAT_POW_MAX
// @Param: BAT_IDX
// @DisplayName: Battery compensation index
// @Description: Which battery monitor should be used for doing compensation
// @Values: 0:First battery, 1:Second battery
// @User: Advanced
AP_GROUPINFO("BAT_IDX", 39, AP_MotorsMulticopter, _batt_idx, 0),
// @Param: SLEW_UP_TIME
// @DisplayName: Output slew time for increasing throttle
// @Description: Time in seconds to slew output from zero to full. For medium size copter such as a Solo, a value of 0.25 is a good starting point. This is used to limit the rate at which output can change. Range is constrained between 0 and 0.5.
// @Range: 0 .5
// @Units: s
// @Increment: 0.001
// @User: Advanced
AP_GROUPINFO("SLEW_UP_TIME", 40, AP_MotorsMulticopter, _slew_up_time, AP_MOTORS_SLEW_TIME_DEFAULT),
// @Param: SLEW_DN_TIME
// @DisplayName: Output slew time for decreasing throttle
// @Description: Time in seconds to slew output from full to zero. For medium size copter such as a Solo, a value of 0.275 is a good starting point. This is used to limit the rate at which output can change. Range is constrained between 0 and 0.5.
// @Range: 0 .5
// @Units: s
// @Increment: 0.001
// @User: Advanced
AP_GROUPINFO("SLEW_DN_TIME", 41, AP_MotorsMulticopter, _slew_dn_time, AP_MOTORS_SLEW_TIME_DEFAULT),
AP_GROUPEND
};
// Constructor
AP_MotorsMulticopter::AP_MotorsMulticopter(uint16_t loop_rate, uint16_t speed_hz) :
AP_Motors(loop_rate, speed_hz),
_lift_max(1.0f),
_throttle_limit(1.0f)
{
AP_Param::setup_object_defaults(this, var_info);
// setup battery voltage filtering
_batt_voltage_filt.set_cutoff_frequency(AP_MOTORS_BATT_VOLT_FILT_HZ);
_batt_voltage_filt.reset(1.0f);
// default throttle range
_throttle_radio_min = 1100;
_throttle_radio_max = 1900;
};
// output - sends commands to the motors
void AP_MotorsMulticopter::output()
{
// update throttle filter
update_throttle_filter();
// calc filtered battery voltage and lift_max
update_lift_max_from_batt_voltage();
// run spool logic
output_logic();
// calculate thrust
output_armed_stabilizing();
// apply any thrust compensation for the frame
thrust_compensation();
// convert rpy_thrust values to pwm
output_to_motors();
// output any booster throttle
output_boost_throttle();
};
// output booster throttle, if any
void AP_MotorsMulticopter::output_boost_throttle(void)
{
if (_boost_scale > 0) {
float throttle = constrain_float(get_throttle() * _boost_scale, 0, 1);
SRV_Channels::set_output_scaled(SRV_Channel::k_boost_throttle, throttle*1000);
}
}
// sends minimum values out to the motors
void AP_MotorsMulticopter::output_min()
{
set_desired_spool_state(DesiredSpoolState::SHUT_DOWN);
_spool_state = SpoolState::SHUT_DOWN;
output();
}
// update the throttle input filter
void AP_MotorsMulticopter::update_throttle_filter()
{
if (armed()) {
_throttle_filter.apply(_throttle_in, 1.0f/_loop_rate);
// constrain filtered throttle
if (_throttle_filter.get() < 0.0f) {
_throttle_filter.reset(0.0f);
}
if (_throttle_filter.get() > 1.0f) {
_throttle_filter.reset(1.0f);
}
} else {
_throttle_filter.reset(0.0f);
}
}
// return current_limit as a number from 0 ~ 1 in the range throttle_min to throttle_max
float AP_MotorsMulticopter::get_current_limit_max_throttle()
{
AP_BattMonitor &battery = AP::battery();
if (_batt_current_max <= 0 || // return maximum if current limiting is disabled
!_flags.armed || // remove throttle limit if disarmed
!battery.has_current(_batt_idx)) { // no current monitoring is available
_throttle_limit = 1.0f;
return 1.0f;
}
float _batt_resistance = battery.get_resistance(_batt_idx);
if (is_zero(_batt_resistance)) {
_throttle_limit = 1.0f;
return 1.0f;
}
float _batt_current = battery.current_amps(_batt_idx);
// calculate the maximum current to prevent voltage sag below _batt_voltage_min
float batt_current_max = MIN(_batt_current_max, _batt_current + (battery.voltage(_batt_idx)-_batt_voltage_min)/_batt_resistance);
float batt_current_ratio = _batt_current/batt_current_max;
float loop_interval = 1.0f/_loop_rate;
_throttle_limit += (loop_interval/(loop_interval+_batt_current_time_constant))*(1.0f - batt_current_ratio);
// throttle limit drops to 20% between hover and full throttle
_throttle_limit = constrain_float(_throttle_limit, 0.2f, 1.0f);
// limit max throttle
return get_throttle_hover() + ((1.0-get_throttle_hover())*_throttle_limit);
}
// apply_thrust_curve_and_volt_scaling - returns throttle in the range 0 ~ 1
float AP_MotorsMulticopter::apply_thrust_curve_and_volt_scaling(float thrust) const
{
float throttle_ratio = thrust;
// apply thrust curve - domain 0.0 to 1.0, range 0.0 to 1.0
float thrust_curve_expo = constrain_float(_thrust_curve_expo, -1.0f, 1.0f);
if (fabsf(thrust_curve_expo) < 0.001) {
// zero expo means linear, avoid floating point exception for small values
return thrust;
}
if(!is_zero(_batt_voltage_filt.get())) {
throttle_ratio = ((thrust_curve_expo-1.0f) + safe_sqrt((1.0f-thrust_curve_expo)*(1.0f-thrust_curve_expo) + 4.0f*thrust_curve_expo*_lift_max*thrust))/(2.0f*thrust_curve_expo*_batt_voltage_filt.get());
} else {
throttle_ratio = ((thrust_curve_expo-1.0f) + safe_sqrt((1.0f-thrust_curve_expo)*(1.0f-thrust_curve_expo) + 4.0f*thrust_curve_expo*_lift_max*thrust))/(2.0f*thrust_curve_expo);
}
return constrain_float(throttle_ratio, 0.0f, 1.0f);
}
// update_lift_max from battery voltage - used for voltage compensation
void AP_MotorsMulticopter::update_lift_max_from_batt_voltage()
{
// sanity check battery_voltage_min is not too small
// if disabled or misconfigured exit immediately
float _batt_voltage_resting_estimate = AP::battery().voltage_resting_estimate(_batt_idx);
if((_batt_voltage_max <= 0) || (_batt_voltage_min >= _batt_voltage_max) || (_batt_voltage_resting_estimate < 0.25f*_batt_voltage_min)) {
_batt_voltage_filt.reset(1.0f);
_lift_max = 1.0f;
return;
}
_batt_voltage_min = MAX(_batt_voltage_min, _batt_voltage_max * 0.6f);
// contrain resting voltage estimate (resting voltage is actual voltage with sag removed based on current draw and resistance)
_batt_voltage_resting_estimate = constrain_float(_batt_voltage_resting_estimate, _batt_voltage_min, _batt_voltage_max);
// filter at 0.5 Hz
float batt_voltage_filt = _batt_voltage_filt.apply(_batt_voltage_resting_estimate/_batt_voltage_max, 1.0f/_loop_rate);
// calculate lift max
float thrust_curve_expo = constrain_float(_thrust_curve_expo, -1.0f, 1.0f);
_lift_max = batt_voltage_filt*(1-thrust_curve_expo) + thrust_curve_expo*batt_voltage_filt*batt_voltage_filt;
}
float AP_MotorsMulticopter::get_compensation_gain() const
{
// avoid divide by zero
if (_lift_max <= 0.0f) {
return 1.0f;
}
float ret = 1.0f / _lift_max;
#if AP_MOTORS_DENSITY_COMP == 1
// air density ratio is increasing in density / decreasing in altitude
if (_air_density_ratio > 0.3f && _air_density_ratio < 1.5f) {
ret *= 1.0f / constrain_float(_air_density_ratio,0.5f,1.25f);
}
#endif
return ret;
}
// convert actuator output (0~1) range to pwm range
int16_t AP_MotorsMulticopter::output_to_pwm(float actuator)
{
float pwm_output;
if (_spool_state == SpoolState::SHUT_DOWN) {
// in shutdown mode, use PWM 0 or minimum PWM
if (_disarm_disable_pwm && _disarm_safety_timer == 0 && !armed()) {
pwm_output = 0;
} else {
pwm_output = get_pwm_output_min();
}
} else {
// in all other spool modes, covert to desired PWM
pwm_output = get_pwm_output_min() + (get_pwm_output_max()-get_pwm_output_min()) * actuator;
}
return pwm_output;
}
// converts desired thrust to linearized actuator output in a range of 0~1
float AP_MotorsMulticopter::thrust_to_actuator(float thrust_in)
{
thrust_in = constrain_float(thrust_in, 0.0f, 1.0f);
return _spin_min + (_spin_max-_spin_min)*apply_thrust_curve_and_volt_scaling(thrust_in);
}
// adds slew rate limiting to actuator output
void AP_MotorsMulticopter::set_actuator_with_slew(float& actuator_output, float input)
{
/*
If MOT_SLEW_UP_TIME is 0 (default), no slew limit is applied to increasing output.
If MOT_SLEW_DN_TIME is 0 (default), no slew limit is applied to decreasing output.
MOT_SLEW_UP_TIME and MOT_SLEW_DN_TIME are constrained to 0.0~0.5 for sanity.
If spool mode is shutdown, no slew limit is applied to allow immediate disarming of motors.
*/
// Output limits with no slew time applied
float output_slew_limit_up = 1.0f;
float output_slew_limit_dn = 0.0f;
// If MOT_SLEW_UP_TIME is set, calculate the highest allowed new output value, constrained 0.0~1.0
if (is_positive(_slew_up_time)) {
float output_delta_up_max = 1.0f/(constrain_float(_slew_up_time,0.0f,0.5f) * _loop_rate);
output_slew_limit_up = constrain_float(actuator_output + output_delta_up_max, 0.0f, 1.0f);
}
// If MOT_SLEW_DN_TIME is set, calculate the lowest allowed new output value, constrained 0.0~1.0
if (is_positive(_slew_dn_time)) {
float output_delta_dn_max = 1.0f/(constrain_float(_slew_dn_time,0.0f,0.5f) * _loop_rate);
output_slew_limit_dn = constrain_float(actuator_output - output_delta_dn_max, 0.0f, 1.0f);
}
// Constrain change in output to within the above limits
actuator_output = constrain_float(input, output_slew_limit_dn, output_slew_limit_up);
}
// gradually increase actuator output to spin_min
float AP_MotorsMulticopter::actuator_spin_up_to_ground_idle() const
{
return constrain_float(_spin_up_ratio, 0.0f, 1.0f) * _spin_min;
}
// get minimum pwm value that can be output to motors
int16_t AP_MotorsMulticopter::get_pwm_output_min() const
{
// return _pwm_min if both PWM_MIN and PWM_MAX parameters are defined and valid
if ((_pwm_min > 0) && (_pwm_max > 0) && (_pwm_max > _pwm_min)) {
return _pwm_min;
}
return _throttle_radio_min;
}
// get maximum pwm value that can be output to motors
int16_t AP_MotorsMulticopter::get_pwm_output_max() const
{
// return _pwm_max if both PWM_MIN and PWM_MAX parameters are defined and valid
if ((_pwm_min > 0) && (_pwm_max > 0) && (_pwm_max > _pwm_min)) {
return _pwm_max;
}
return _throttle_radio_max;
}
// set_throttle_range - sets the minimum throttle that will be sent to the engines when they're not off (i.e. to prevents issues with some motors spinning and some not at very low throttle)
// also sets throttle channel minimum and maximum pwm
void AP_MotorsMulticopter::set_throttle_range(int16_t radio_min, int16_t radio_max)
{
// sanity check
if (radio_max <= radio_min) {
return;
}
_throttle_radio_min = radio_min;
_throttle_radio_max = radio_max;
if (_pwm_type >= PWM_TYPE_DSHOT150 && _pwm_type <= PWM_TYPE_DSHOT1200) {
// force PWM range for DShot ESCs
_pwm_min.set(1000);
_pwm_max.set(2000);
}
hal.rcout->set_esc_scaling(get_pwm_output_min(), get_pwm_output_max());
}
// update the throttle input filter. should be called at 100hz
void AP_MotorsMulticopter::update_throttle_hover(float dt)
{
if (_throttle_hover_learn != HOVER_LEARN_DISABLED) {
// we have chosen to constrain the hover throttle to be within the range reachable by the third order expo polynomial.
_throttle_hover = constrain_float(_throttle_hover + (dt/(dt+AP_MOTORS_THST_HOVER_TC))*(get_throttle()-_throttle_hover), AP_MOTORS_THST_HOVER_MIN, AP_MOTORS_THST_HOVER_MAX);
}
}
// run spool logic
void AP_MotorsMulticopter::output_logic()
{
if (_flags.armed) {
_disarm_safety_timer = 100;
} else if (_disarm_safety_timer != 0) {
_disarm_safety_timer--;
}
// force desired and current spool mode if disarmed or not interlocked
if (!_flags.armed || !_flags.interlock) {
_spool_desired = DesiredSpoolState::SHUT_DOWN;
_spool_state = SpoolState::SHUT_DOWN;
}
if (_spool_up_time < 0.05) {
// prevent float exception
_spool_up_time.set(0.05);
}
switch (_spool_state) {
case SpoolState::SHUT_DOWN:
// Motors should be stationary.
// Servos set to their trim values or in a test condition.
// set limits flags
limit.roll_pitch = true;
limit.yaw = true;
limit.throttle_lower = true;
limit.throttle_upper = true;
// make sure the motors are spooling in the correct direction
if (_spool_desired != DesiredSpoolState::SHUT_DOWN) {
_spool_state = SpoolState::GROUND_IDLE;
break;
}
// set and increment ramp variables
_spin_up_ratio = 0.0f;
_throttle_thrust_max = 0.0f;
// initialise motor failure variables
_thrust_boost = false;
_thrust_boost_ratio = 0.0f;
break;
case SpoolState::GROUND_IDLE: {
// Motors should be stationary or at ground idle.
// Servos should be moving to correct the current attitude.
// set limits flags
limit.roll_pitch = true;
limit.yaw = true;
limit.throttle_lower = true;
limit.throttle_upper = true;
// set and increment ramp variables
float spool_step = 1.0f/(_spool_up_time*_loop_rate);
switch (_spool_desired) {
case DesiredSpoolState::SHUT_DOWN:
_spin_up_ratio -= spool_step;
// constrain ramp value and update mode
if (_spin_up_ratio <= 0.0f) {
_spin_up_ratio = 0.0f;
_spool_state = SpoolState::SHUT_DOWN;
}
break;
case DesiredSpoolState::THROTTLE_UNLIMITED:
_spin_up_ratio += spool_step;
// constrain ramp value and update mode
if (_spin_up_ratio >= 1.0f) {
_spin_up_ratio = 1.0f;
_spool_state = SpoolState::SPOOLING_UP;
}
break;
case DesiredSpoolState::GROUND_IDLE:
float spin_up_armed_ratio = 0.0f;
if (_spin_min > 0.0f) {
spin_up_armed_ratio = _spin_arm / _spin_min;
}
_spin_up_ratio += constrain_float(spin_up_armed_ratio-_spin_up_ratio, -spool_step, spool_step);
break;
}
_throttle_thrust_max = 0.0f;
// initialise motor failure variables
_thrust_boost = false;
_thrust_boost_ratio = 0.0f;
break;
}
case SpoolState::SPOOLING_UP:
// Maximum throttle should move from minimum to maximum.
// Servos should exhibit normal flight behavior.
// initialize limits flags
limit.roll_pitch = false;
limit.yaw = false;
limit.throttle_lower = false;
limit.throttle_upper = false;
// make sure the motors are spooling in the correct direction
if (_spool_desired != DesiredSpoolState::THROTTLE_UNLIMITED ){
_spool_state = SpoolState::SPOOLING_DOWN;
break;
}
// set and increment ramp variables
_spin_up_ratio = 1.0f;
_throttle_thrust_max += 1.0f/(_spool_up_time*_loop_rate);
// constrain ramp value and update mode
if (_throttle_thrust_max >= MIN(get_throttle(), get_current_limit_max_throttle())) {
_throttle_thrust_max = get_current_limit_max_throttle();
_spool_state = SpoolState::THROTTLE_UNLIMITED;
} else if (_throttle_thrust_max < 0.0f) {
_throttle_thrust_max = 0.0f;
}
// initialise motor failure variables
_thrust_boost = false;
_thrust_boost_ratio = MAX(0.0, _thrust_boost_ratio - 1.0 / (_spool_up_time * _loop_rate));
break;
case SpoolState::THROTTLE_UNLIMITED:
// Throttle should exhibit normal flight behavior.
// Servos should exhibit normal flight behavior.
// initialize limits flags
limit.roll_pitch = false;
limit.yaw = false;
limit.throttle_lower = false;
limit.throttle_upper = false;
// make sure the motors are spooling in the correct direction
if (_spool_desired != DesiredSpoolState::THROTTLE_UNLIMITED) {
_spool_state = SpoolState::SPOOLING_DOWN;
break;
}
// set and increment ramp variables
_spin_up_ratio = 1.0f;
_throttle_thrust_max = get_current_limit_max_throttle();
if (_thrust_boost && !_thrust_balanced) {
_thrust_boost_ratio = MIN(1.0, _thrust_boost_ratio+1.0f/(_spool_up_time*_loop_rate));
} else {
_thrust_boost_ratio = MAX(0.0, _thrust_boost_ratio-1.0f/(_spool_up_time*_loop_rate));
}
break;
case SpoolState::SPOOLING_DOWN:
// Maximum throttle should move from maximum to minimum.
// Servos should exhibit normal flight behavior.
// initialize limits flags
limit.roll_pitch = false;
limit.yaw = false;
limit.throttle_lower = false;
limit.throttle_upper = false;
// make sure the motors are spooling in the correct direction
if (_spool_desired == DesiredSpoolState::THROTTLE_UNLIMITED) {
_spool_state = SpoolState::SPOOLING_UP;
break;
}
// set and increment ramp variables
_spin_up_ratio = 1.0f;
_throttle_thrust_max -= 1.0f/(_spool_up_time*_loop_rate);
// constrain ramp value and update mode
if (_throttle_thrust_max <= 0.0f){
_throttle_thrust_max = 0.0f;
}
if (_throttle_thrust_max >= get_current_limit_max_throttle()) {
_throttle_thrust_max = get_current_limit_max_throttle();
} else if (is_zero(_throttle_thrust_max)) {
_spool_state = SpoolState::GROUND_IDLE;
}
_thrust_boost_ratio = MAX(0.0, _thrust_boost_ratio-1.0f/(_spool_up_time*_loop_rate));
break;
}
}
// passes throttle directly to all motors for ESC calibration.
// throttle_input is in the range of 0 ~ 1 where 0 will send get_pwm_output_min() and 1 will send get_pwm_output_max()
void AP_MotorsMulticopter::set_throttle_passthrough_for_esc_calibration(float throttle_input)
{
if (armed()) {
uint16_t pwm_out = get_pwm_output_min() + constrain_float(throttle_input, 0.0f, 1.0f) * (get_pwm_output_max() - get_pwm_output_min());
// send the pilot's input directly to each enabled motor
for (uint16_t i=0; i < AP_MOTORS_MAX_NUM_MOTORS; i++) {
if (motor_enabled[i]) {
rc_write(i, pwm_out);
}
}
// send pwm output to channels used by bicopter
SRV_Channels::set_output_pwm(SRV_Channel::k_throttleRight, pwm_out);
SRV_Channels::set_output_pwm(SRV_Channel::k_throttleLeft, pwm_out);
}
}
// output a thrust to all motors that match a given motor mask. This
// is used to control tiltrotor motors in forward flight. Thrust is in
// the range 0 to 1
void AP_MotorsMulticopter::output_motor_mask(float thrust, uint8_t mask, float rudder_dt)
{
for (uint8_t i=0; i<AP_MOTORS_MAX_NUM_MOTORS; i++) {
if (motor_enabled[i]) {
if (mask & (1U<<i)) {
/*
apply rudder mixing differential thrust
copter frame roll is plane frame yaw as this only
apples to either tilted motors or tailsitters
*/
float diff_thrust = get_roll_factor(i) * rudder_dt * 0.5f;
set_actuator_with_slew(_actuator[i], thrust_to_actuator(thrust + diff_thrust));
int16_t pwm_output = get_pwm_output_min() +
(get_pwm_output_max()-get_pwm_output_min()) * _actuator[i];
rc_write(i, pwm_output);
} else {
rc_write(i, get_pwm_output_min());
}
}
}
}
// get_motor_mask - returns a bitmask of which outputs are being used for motors (1 means being used)
// this can be used to ensure other pwm outputs (i.e. for servos) do not conflict
uint16_t AP_MotorsMulticopter::get_motor_mask()
{
return SRV_Channels::get_output_channel_mask(SRV_Channel::k_boost_throttle);
}
// save parameters as part of disarming
void AP_MotorsMulticopter::save_params_on_disarm()
{
// save hover throttle
if (_throttle_hover_learn == HOVER_LEARN_AND_SAVE) {
_throttle_hover.save();
}
}