AP_VisualOdom: added VOXL backend type

this will make it easier to have custom behaviour for VOXL

libraries/AP_VisualOdom/AP_VisualOdom.cpp

@@ -31,7 +31,7 @@ const AP_Param::GroupInfo AP_VisualOdom::var_info[] = {
     // @Param: _TYPE
     // @DisplayName: Visual odometry camera connection type
     // @Description: Visual odometry camera connection type
-    // @Values: 0:None,1:MAVLink,2:IntelT265
+    // @Values: 0:None,1:MAVLink,2:IntelT265,3:VOXL(ModalAI)
     // @User: Advanced
     // @RebootRequired: True
     AP_GROUPINFO_FLAGS("_TYPE", 0, AP_VisualOdom, _type, 0, AP_PARAM_FLAG_ENABLE),
@@ -124,14 +124,15 @@ AP_VisualOdom::AP_VisualOdom()
 void AP_VisualOdom::init()
 {
     // create backend
-    switch (_type) {
-    case AP_VisualOdom_Type_None:
+    switch (VisualOdom_Type(_type.get())) {
+    case VisualOdom_Type::None:
         // do nothing
         break;
-    case AP_VisualOdom_Type_MAV:
+    case VisualOdom_Type::MAV:
         _driver = new AP_VisualOdom_MAV(*this);
         break;
-    case AP_VisualOdom_Type_IntelT265:
+    case VisualOdom_Type::IntelT265:
+    case VisualOdom_Type::VOXL:
         _driver = new AP_VisualOdom_IntelT265(*this);
         break;
     }
@@ -140,7 +141,7 @@ void AP_VisualOdom::init()
 // return true if sensor is enabled
 bool AP_VisualOdom::enabled() const
 {
-    return ((_type != AP_VisualOdom_Type_None));
+    return ((_type != VisualOdom_Type::None));
 }
 
 // return true if sensor is basically healthy (we are receiving data)

libraries/AP_VisualOdom/AP_VisualOdom.h

@@ -44,10 +44,11 @@ public:
     }
 
     // external position backend types (used by _TYPE parameter)
-    enum AP_VisualOdom_Type {
-        AP_VisualOdom_Type_None         = 0,
-        AP_VisualOdom_Type_MAV          = 1,
-        AP_VisualOdom_Type_IntelT265    = 2
+    enum class VisualOdom_Type {
+        None         = 0,
+        MAV          = 1,
+        IntelT265    = 2,
+        VOXL         = 3,
     };
 
     // detect and initialise any sensors
@@ -106,12 +107,16 @@ public:
 
     static const struct AP_Param::GroupInfo var_info[];
 
+    VisualOdom_Type get_type(void) const {
+        return _type;
+    }
+
 private:
 
     static AP_VisualOdom *_singleton;
 
     // parameters
-    AP_Int8 _type;              // sensor type
+    AP_Enum<VisualOdom_Type> _type; // sensor type
     AP_Vector3f _pos_offset;    // position offset of the camera in the body frame
     AP_Int8 _orientation;       // camera orientation on vehicle frame
     AP_Float _pos_scale;        // position scale factor applied to sensor values

libraries/AP_VisualOdom/AP_VisualOdom_Backend.h

@@ -51,6 +51,10 @@ protected:
     // updates the reset timestamp to the current system time if the reset_counter has changed
     uint32_t get_reset_timestamp_ms(uint8_t reset_counter);
 
+    AP_VisualOdom::VisualOdom_Type get_type(void) const {
+        return _frontend.get_type();
+    }
+
     // Logging Functions
     void Write_VisualOdom(float time_delta, const Vector3f &angle_delta, const Vector3f &position_delta, float confidence);
     void Write_VisualPosition(uint64_t remote_time_us, uint32_t time_ms, float x, float y, float z, float roll, float pitch, float yaw, float pos_err, float ang_err, uint8_t reset_counter, bool ignored);

libraries/AP_VisualOdom/AP_VisualOdom_IntelT265.cpp

@@ -261,6 +261,11 @@ bool AP_VisualOdom_IntelT265::pre_arm_check(char *failure_msg, uint8_t failure_m
 // only the VISION_POSITION_ESTIMATE message's reset_counter is used to determine if sensor data should be ignored
 bool AP_VisualOdom_IntelT265::should_consume_sensor_data(bool vision_position_estimate, uint8_t reset_counter)
 {
+    if (get_type() == AP_VisualOdom::VisualOdom_Type::VOXL) {
+        // we don't discard data after a reset for VOXL
+        return true;
+    }
+
     uint32_t now_ms = AP_HAL::millis();
 
     // set ignore start time if reset counter has changed