libraries/AP_Parachute/AP_Parachute.h

   1 /// @file   AP_Parachute.h
   2 /// @brief  Parachute release library
   3 #pragma once
   4
   5 #include "AP_Parachute_config.h"
   6
   7 #if HAL_PARACHUTE_ENABLED
   8
   9 #include <AP_Param/AP_Param.h>
  10 #include <AP_Common/AP_Common.h>
  11
  12 #define AP_PARACHUTE_TRIGGER_TYPE_RELAY_0       0
  13 #define AP_PARACHUTE_TRIGGER_TYPE_RELAY_1       1
  14 #define AP_PARACHUTE_TRIGGER_TYPE_RELAY_2       2
  15 #define AP_PARACHUTE_TRIGGER_TYPE_RELAY_3       3
  16 #define AP_PARACHUTE_TRIGGER_TYPE_SERVO         10
  17
  18 #define AP_PARACHUTE_RELEASE_DELAY_MS           500    // delay in milliseconds between call to release() and when servo or relay actually moves.  Allows for warning to user
  19 #define AP_PARACHUTE_RELEASE_DURATION_MS       2000    // when parachute is released, servo or relay stay at their released position/value for 2000ms (2seconds)
  20
  21 #define AP_PARACHUTE_SERVO_ON_PWM_DEFAULT      1300    // default PWM value to move servo to when shutter is activated
  22 #define AP_PARACHUTE_SERVO_OFF_PWM_DEFAULT     1100    // default PWM value to move servo to when shutter is deactivated
  23
  24 #define AP_PARACHUTE_ALT_MIN_DEFAULT            10     // default min altitude the vehicle should have before parachute is released
  25
  26 #define AP_PARACHUTE_CRITICAL_SINK_DEFAULT      0      // default critical sink speed in m/s to trigger emergency parachute
  27 #define AP_PARACHUTE_OPTIONS_DEFAULT            0      // default parachute options: enabled disarm after parachute release
  28
  29 /// @class  AP_Parachute
  30 /// @brief  Class managing the release of a parachute
  31 class AP_Parachute {
  32
  33 public:
  34     /// Constructor
  35     AP_Parachute()
  36     {
  37         // setup parameter defaults
  38 #if CONFIG_HAL_BOARD == HAL_BOARD_SITL
  39         if (_singleton != nullptr) {
  40             AP_HAL::panic("Parachute must be singleton");
  41         }
  42 #endif
  43         _singleton = this;
  44         AP_Param::setup_object_defaults(this, var_info);
  45     }
  46
  47     /* Do not allow copies */
  48     CLASS_NO_COPY(AP_Parachute);
  49
  50     /// enabled - enable or disable parachute release
  51     void enabled(bool on_off);
  52
  53     /// enabled - returns true if parachute release is enabled
  54     bool enabled() const { return _enabled; }
  55
  56     /// release - release parachute
  57     void release();
  58
  59     /// released - true if the parachute has been released (or release is in progress)
  60     bool released() const { return _released; }
  61
  62     /// release_initiated - true if the parachute release sequence has been initiated (may wait before actual release)
  63     bool release_initiated() const { return _release_initiated; }
  64
  65     /// release_in_progress - true if the parachute release sequence is in progress
  66     bool release_in_progress() const { return _release_in_progress; }
  67
  68     /// update - shuts off the trigger should be called at about 10hz
  69     void update();
  70
  71     /// alt_min - returns the min altitude above home the vehicle should have before parachute is released
  72     ///   0 = altitude check disabled
  73     int16_t alt_min() const { return _alt_min; }
  74
  75     /// set_is_flying - accessor to the is_flying flag
  76     void set_is_flying(const bool is_flying) { _is_flying = is_flying; }
  77
  78     // set_sink_rate - set vehicle sink rate
  79     void set_sink_rate(float sink_rate);
  80
  81     // trigger parachute release if sink_rate is below critical_sink_rate for 1sec
  82     void check_sink_rate();
  83
  84     // check settings are valid
  85     bool arming_checks(size_t buflen, char *buffer) const;
  86
  87     // Return the relay index that would be used for param conversion to relay functions
  88     bool get_legacy_relay_index(int8_t &index) const;
  89
  90     static const struct AP_Param::GroupInfo        var_info[];
  91
  92     // get singleton instance
  93     static AP_Parachute *get_singleton() { return _singleton; }
  94
  95 private:
  96     static AP_Parachute *_singleton;
  97     // Parameters
  98     AP_Int8     _enabled;       // 1 if parachute release is enabled
  99     AP_Int8     _release_type;  // 0:Servo,1:Relay
 100     AP_Int16    _servo_on_pwm;  // PWM value to move servo to when shutter is activated
 101     AP_Int16    _servo_off_pwm; // PWM value to move servo to when shutter is deactivated
 102     AP_Int16    _alt_min;       // min altitude the vehicle should have before parachute is released
 103     AP_Int16    _delay_ms;      // delay before chute release for motors to stop
 104     AP_Float    _critical_sink;      // critical sink rate to trigger emergency parachute
 105
 106     // internal variables
 107     uint32_t    _release_time;  // system time that parachute is ordered to be released (actual release will happen 0.5 seconds later)
 108     bool        _release_initiated:1;    // true if the parachute release initiated (may still be waiting for engine to be suppressed etc.)
 109     bool        _release_in_progress:1;  // true if the parachute release is in progress
 110     bool        _released:1;             // true if the parachute has been released
 111     bool        _is_flying:1;            // true if the vehicle is flying
 112     uint32_t    _sink_time_ms;           // system time that the vehicle exceeded critical sink rate
 113
 114     enum class Options : uint8_t {
 115         HoldOpen = (1U<<0),
 116         SkipDisarmBeforeParachuteRelease = (1U<<1),
 117     };
 118
 119     AP_Int32    _options;
 120 };
 121
 122 namespace AP {
 123     AP_Parachute *parachute();
 124 };
 125
 126 #endif // HAL_PARACHUTE_ENABLED