px4flow : publish sensor limits over uORB

src/drivers/px4flow/px4flow.cpp

@@ -143,7 +143,11 @@ private:
 	perf_counter_t		_comms_errors;
 
 	unsigned                 _conversion_interval;
+
 	enum Rotation       _sensor_rotation;
+	float 				_sensor_min_range;
+	float 				_sensor_max_range;
+	float 				_sensor_max_flow_rate;
 
 	/**
 	 * Test whether the device supported by the driver is present at a
@@ -267,7 +271,6 @@ PX4FLOW::init()
 	/* get yaw rotation from sensor frame to body frame */
 	param_t rot = param_find("SENS_FLOW_ROT");
 
-	/* only set it if the parameter exists */
 	if (rot != PARAM_INVALID) {
 		int32_t val = 6; // the recommended installation for the flow sensor is with the Y sensor axis forward
 		param_get(rot, &val);
@@ -275,6 +278,34 @@ PX4FLOW::init()
 		_sensor_rotation = (enum Rotation)val;
 	}
 
+	/* get operational limits of the sensor */
+	param_t hmin = param_find("SENS_FLOW_MINHGT");
+
+	if (hmin != PARAM_INVALID) {
+		float val = 0.7;
+		param_get(hmin, &val);
+
+		_sensor_min_range = val;
+	}
+
+	param_t hmax = param_find("SENS_FLOW_MAXHGT");
+
+	if (hmax != PARAM_INVALID) {
+		float val = 3.0;
+		param_get(hmax, &val);
+
+		_sensor_max_range = val;
+	}
+
+	param_t ratemax = param_find("SENS_FLOW_MAXR");
+
+	if (ratemax != PARAM_INVALID) {
+		float val = 2.5;
+		param_get(ratemax, &val);
+
+		_sensor_max_flow_rate = val;
+	}
+
 	return ret;
 }
 
@@ -536,6 +567,12 @@ PX4FLOW::collect()
 
 	report.sensor_id = 0;
 
+	report.max_flow_rate = _sensor_max_flow_rate;
+
+	report.min_ground_distance = _sensor_min_range;
+
+	report.max_ground_distance = _sensor_max_range;
+
 	/* rotate measurements in yaw from sensor frame to body frame according to parameter SENS_FLOW_ROT */
 	float zeroval = 0.0f;