AC_PosControl: remove alt_max

AC_Avoidance enforces the altitude limit

libraries/AC_AttitudeControl/AC_PosControl.cpp

@@ -52,7 +52,6 @@ AC_PosControl::AC_PosControl(const AP_AHRS& ahrs, const AP_InertialNav& inav,
     _leash_up_z(POSCONTROL_LEASH_LENGTH_MIN),
     _roll_target(0.0f),
     _pitch_target(0.0f),
-    _alt_max(0.0f),
     _distance_to_target(0.0f),
     _accel_target_jerk_limited(0.0f,0.0f),
     _accel_target_filter(POSCONTROL_ACCEL_FILTER_HZ)
@@ -166,12 +165,6 @@ void AC_PosControl::set_alt_target_from_climb_rate(float climb_rate_cms, float d
         _pos_target.z += climb_rate_cms * dt;
     }
 
-    // do not let target alt get above limit
-    if (_alt_max > 0 && _pos_target.z > _alt_max) {
-        _pos_target.z = _alt_max;
-        _limit.pos_up = true;
-    }
-
     // do not use z-axis desired velocity feed forward
     // vel_desired set to desired climb rate for reporting and land-detector
     _flags.use_desvel_ff_z = false;
@@ -212,14 +205,6 @@ void AC_PosControl::set_alt_target_from_climb_rate_ff(float climb_rate_cms, floa
     if ((_vel_desired.z<0 && (!_motors.limit.throttle_lower || force_descend)) || (_vel_desired.z>0 && !_motors.limit.throttle_upper && !_limit.pos_up)) {
         _pos_target.z += _vel_desired.z * dt;
     }
-
-    // do not let target alt get above limit
-    if (_alt_max > 0 && _pos_target.z > _alt_max) {
-        _pos_target.z = _alt_max;
-        _limit.pos_up = true;
-        // decelerate feed forward to zero
-        _vel_desired.z = constrain_float(0.0f, _vel_desired.z-vel_change_limit, _vel_desired.z+vel_change_limit);
-    }
 }
 
 /// add_takeoff_climb_rate - adjusts alt target up or down using a climb rate in cm/s

libraries/AC_AttitudeControl/AC_PosControl.h

@@ -76,11 +76,6 @@ public:
     /// z position controller
     ///
 
-    /// set_alt_max - sets maximum altitude above the ekf origin in cm
-    ///   only enforced when set_alt_target_from_climb_rate is used
-    ///   set to zero to disable limit
-    void set_alt_max(float alt) { _alt_max = alt; }
-
     /// set_speed_z - sets maximum climb and descent rates
     ///     speed_down can be positive or negative but will always be interpreted as a descent speed
     ///     leash length will be recalculated the next time update_z_controller() is called
@@ -417,7 +412,6 @@ private:
     Vector3f    _accel_error;           // desired acceleration in cm/s/s  // To-Do: are xy actually required?
     Vector3f    _accel_feedforward;     // feedforward acceleration in cm/s/s
     Vector2f    _vehicle_horiz_vel;     // velocity to use if _flags.vehicle_horiz_vel_override is set
-    float       _alt_max;               // max altitude - should be updated from the main code with altitude limit from fence
     float       _distance_to_target;    // distance to position target - for reporting only
     LowPassFilterFloat _vel_error_filter;   // low-pass-filter on z-axis velocity error