src/main/flight/pid.h

   1 /*
   2  * This file is part of Cleanflight.
   3  *
   4  * Cleanflight is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 3 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * Cleanflight is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with Cleanflight.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #pragma once
  19
  20 #include "config/parameter_group.h"
  21 #include "fc/runtime_config.h"
  22
  23 #define GYRO_SATURATION_LIMIT       1800        // 1800dps
  24 #define PID_SUM_LIMIT_MIN           100
  25 #define PID_SUM_LIMIT_MAX           1000
  26 #define PID_SUM_LIMIT_DEFAULT       500
  27 #define PID_SUM_LIMIT_YAW_DEFAULT   350
  28
  29 #define HEADING_HOLD_RATE_LIMIT_MIN 10
  30 #define HEADING_HOLD_RATE_LIMIT_MAX 250
  31 #define HEADING_HOLD_RATE_LIMIT_DEFAULT 90
  32
  33 #define FW_ITERM_THROW_LIMIT_DEFAULT 165
  34 #define FW_ITERM_THROW_LIMIT_MIN 0
  35 #define FW_ITERM_THROW_LIMIT_MAX 500
  36
  37 #define AXIS_ACCEL_MIN_LIMIT        50
  38
  39 #define HEADING_HOLD_ERROR_LPF_FREQ 2
  40
  41 /*
  42 FP-PID has been rescaled to match LuxFloat (and MWRewrite) from Cleanflight 1.13
  43 */
  44 #define FP_PID_RATE_FF_MULTIPLIER   31.0f
  45 #define FP_PID_RATE_P_MULTIPLIER    31.0f
  46 #define FP_PID_RATE_I_MULTIPLIER    4.0f
  47 #define FP_PID_RATE_D_MULTIPLIER    1905.0f
  48 #define FP_PID_RATE_D_FF_MULTIPLIER   7270.0f
  49 #define FP_PID_LEVEL_P_MULTIPLIER   6.56f       // Level P gain units is [1/sec] and angle error is [deg] => [deg/s]
  50 #define FP_PID_YAWHOLD_P_MULTIPLIER 80.0f
  51
  52 #define MC_ITERM_RELAX_SETPOINT_THRESHOLD 40.0f
  53 #define MC_ITERM_RELAX_CUTOFF_DEFAULT 15
  54
  55 #define ANTI_GRAVITY_THROTTLE_FILTER_CUTOFF 15  // The anti gravity throttle highpass filter cutoff
  56
  57 typedef enum {
  58     /* PID              MC      FW  */
  59     PID_ROLL,       //   +       +
  60     PID_PITCH,      //   +       +
  61     PID_YAW,        //   +       +
  62     PID_POS_Z,      //   +       +
  63     PID_POS_XY,     //   +       +
  64     PID_VEL_XY,     //   +       n/a
  65     PID_SURFACE,    //   n/a     n/a
  66     PID_LEVEL,      //   +       +
  67     PID_HEADING,    //   +       +
  68     PID_VEL_Z,      //   +       n/a
  69     PID_POS_HEADING,//   n/a     +
  70     PID_ITEM_COUNT
  71 } pidIndex_e;
  72
  73 // TODO(agh): PIDFF
  74 typedef enum {
  75     PID_TYPE_NONE = 0,  // Not used in the current platform/mixer/configuration
  76     PID_TYPE_PID,   // Uses P, I and D terms
  77     PID_TYPE_PIFF,  // Uses P, I and FF, ignoring D
  78     PID_TYPE_AUTO,  // Autodetect
  79 } pidType_e;
  80
  81 typedef struct pid8_s {
  82     uint8_t P;
  83     uint8_t I;
  84     uint8_t D;
  85     uint8_t FF;
  86 } pid8_t;
  87
  88 typedef struct pidBank_s {
  89     pid8_t  pid[PID_ITEM_COUNT];
  90 } pidBank_t;
  91
  92 typedef enum {
  93     ITERM_RELAX_OFF = 0,
  94     ITERM_RELAX_RP,
  95     ITERM_RELAX_RPY
  96 } itermRelax_e;
  97
  98 typedef enum {
  99     ITERM_RELAX_GYRO = 0,
 100     ITERM_RELAX_SETPOINT
 101 } itermRelaxType_e;
 102
 103 typedef struct pidProfile_s {
 104     uint8_t pidControllerType;
 105     pidBank_t bank_fw;
 106     pidBank_t bank_mc;
 107
 108     uint8_t dterm_lpf_type;                 // Dterm LPF type: PT1, BIQUAD
 109     uint16_t dterm_lpf_hz;
 110
 111     uint8_t dterm_lpf2_type;                // Dterm LPF type: PT1, BIQUAD
 112     uint16_t dterm_lpf2_hz;
 113
 114     uint8_t yaw_lpf_hz;
 115
 116     uint8_t heading_hold_rate_limit;        // Maximum rotation rate HEADING_HOLD mode can feed to yaw rate PID controller
 117
 118     uint8_t itermWindupPointPercent;        // Experimental ITerm windup threshold, percent of motor saturation
 119
 120     uint32_t axisAccelerationLimitYaw;          // Max rate of change of yaw angular rate setpoint (deg/s^2 = dps/s)
 121     uint32_t axisAccelerationLimitRollPitch;    // Max rate of change of roll/pitch angular rate setpoint (deg/s^2 = dps/s)
 122
 123     int16_t max_angle_inclination[ANGLE_INDEX_COUNT];       // Max possible inclination (roll and pitch axis separately
 124
 125     uint16_t pidSumLimit;
 126     uint16_t pidSumLimitYaw;
 127
 128     // Airplane-specific parameters
 129     uint16_t    fixedWingItermThrowLimit;
 130     float       fixedWingReferenceAirspeed;     // Reference tuning airspeed for the airplane - the speed for which PID gains are tuned
 131     float       fixedWingCoordinatedYawGain;    // This is the gain of the yaw rate required to keep the yaw rate consistent with the turn rate for a coordinated turn.
 132     float       fixedWingItermLimitOnStickPosition;   //Do not allow Iterm to grow when stick position is above this point
 133
 134     uint8_t     loiter_direction;               // Direction of loitering center point on right wing (clockwise - as before), or center point on left wing (counterclockwise)
 135     float       navVelXyDTermLpfHz;
 136
 137     uint8_t iterm_relax_type;               // Specifies type of relax algorithm
 138     uint8_t iterm_relax_cutoff;             // This cutoff frequency specifies a low pass filter which predicts average response of the quad to setpoint
 139     uint8_t iterm_relax;                    // Enable iterm suppression during stick input
 140
 141     float dBoostFactor;
 142     float dBoostMaxAtAlleceleration;
 143     uint8_t dBoostGyroDeltaLpfHz;
 144     float antigravityGain;
 145     float antigravityAccelerator;
 146     uint8_t antigravityCutoff;
 147
 148     uint16_t navFwPosHdgPidsumLimit;
 149     uint8_t controlDerivativeLpfHz;
 150 } pidProfile_t;
 151
 152 typedef struct pidAutotuneConfig_s {
 153     uint16_t    fw_overshoot_time;          // Time [ms] to detect sustained overshoot
 154     uint16_t    fw_undershoot_time;         // Time [ms] to detect sustained undershoot
 155     uint8_t     fw_max_rate_threshold;      // Threshold [%] of max rate to consider autotune detection
 156     uint8_t     fw_ff_to_p_gain;            // FF to P gain (strength relationship) [%]
 157     uint16_t    fw_ff_to_i_time_constant;   // FF to I time (defines time for I to reach the same level of response as FF) [ms]
 158 } pidAutotuneConfig_t;
 159
 160 PG_DECLARE_PROFILE(pidProfile_t, pidProfile);
 161 PG_DECLARE(pidAutotuneConfig_t, pidAutotuneConfig);
 162
 163 const pidBank_t * pidBank(void);
 164 pidBank_t * pidBankMutable(void);
 165
 166 extern int16_t axisPID[];
 167 extern int32_t axisPID_P[], axisPID_I[], axisPID_D[], axisPID_Setpoint[];
 168
 169 void pidInit(void);
 170 bool pidInitFilters(void);
 171 void pidResetErrorAccumulators(void);
 172 void pidResetTPAFilter(void);
 173
 174 struct controlRateConfig_s;
 175 struct motorConfig_s;
 176 struct rxConfig_s;
 177
 178 void schedulePidGainsUpdate(void);
 179 void updatePIDCoefficients(float dT);
 180 void pidController(float dT);
 181
 182 float pidRateToRcCommand(float rateDPS, uint8_t rate);
 183 int16_t pidAngleToRcCommand(float angleDeciDegrees, int16_t maxInclination);
 184
 185 enum {
 186     HEADING_HOLD_DISABLED = 0,
 187     HEADING_HOLD_UPDATE_HEADING,
 188     HEADING_HOLD_ENABLED
 189 };
 190
 191 void updateHeadingHoldTarget(int16_t heading);
 192 void resetHeadingHoldTarget(int16_t heading);
 193 int16_t getHeadingHoldTarget(void);
 194
 195 void autotuneUpdateState(void);
 196 void autotuneFixedWingUpdate(const flight_dynamics_index_t axis, float desiredRateDps, float reachedRateDps, float pidOutput);
 197
 198 pidType_e pidIndexGetType(pidIndex_e pidIndex);