Fix sensordata reference frame definitions

- Remove incorrect parent frame definition for detected moving object
- Clarify definition of parent frame for all sensordata objects

Signed-off-by: Thomas Sedlmayer <tsedlmayer@pmsfit.de>

Author: thomassedlmayer

osi_detectedlane.proto

@@ -54,6 +54,15 @@ message DetectedLane
 //
 // \image html OSI_DetectedLaneBoundary.svg
 //
+// The parent frame of a detected lane boundary is the virtual sensor coordinate
+// system.
+//
+// The virtual sensor coordinate system is relative to the vehicle coordinate
+// system which has its origin in the center of the rear axle of the ego
+// vehicle. This means if virtual sensor mounting position and orientation are
+// set to (0,0,0) the virtual sensor coordinate system coincides with the
+// vehicle coordinate system.
+//
 message DetectedLaneBoundary
 {
     // Common information of one detected item.

osi_detectedobject.proto

@@ -93,6 +93,15 @@ message DetectedItemHeader
 //
 // \image html OSI_DetectedStationaryObject.svg
 //
+// The parent frame of a detected stationary object is the virtual sensor
+// coordinate system.
+//
+// The virtual sensor coordinate system is relative to the vehicle coordinate
+// system which has its origin in the center of the rear axle of the ego
+// vehicle. This means if virtual sensor mounting position and orientation are
+// set to (0,0,0) the virtual sensor coordinate system coincides with the
+// vehicle coordinate system.
+//
 message DetectedStationaryObject
 {
     // Common information of one detected item.
@@ -172,8 +181,17 @@ message DetectedStationaryObject
 }
 
 //
-// \brief Moving object in the environment as detected and perceived by
-// the sensor.
+// \brief Moving object in the environment as detected and perceived by the
+// sensor.
+//
+// The parent frame of a detected moving object is the virtual sensor coordinate
+// system.
+//
+// The virtual sensor coordinate system is relative to the vehicle coordinate
+// system which has its origin in the center of the rear axle of the ego
+// vehicle. This means if virtual sensor mounting position and orientation are
+// set to (0,0,0) the virtual sensor coordinate system coincides with the
+// vehicle coordinate system.
 //
 message DetectedMovingObject
 {
@@ -183,8 +201,7 @@ message DetectedMovingObject
 
     // The base parameters of the moving object.
     //
-    // \note The bounding box does NOT includes mirrors for vehicles.
-    // \note The parent frame of \c base is the sensor's vehicle frame.
+    // \note The bounding box does NOT include mirrors for vehicles.
     // \note The height includes the ground_clearance. It always goes from the
     // top to the ground.
     //
@@ -194,8 +211,6 @@ message DetectedMovingObject
     // moving object (e.g. car). \c MovingObject::base has to be
     // identical for all \c #candidate moving objects.
     //
-    // \note The parent frame of \c base is the sensor's vehicle frame.
-    //
     optional BaseMoving base_rmse = 3;
 
     // Reference point location specification of the sensor measurement

osi_detectedroadmarking.proto

@@ -20,6 +20,15 @@ package osi3;
 // RoadMarking::Classification::type == \c
 // RoadMarking::Classification::TYPE_SYMBOLIC_TRAFFIC_SIGN is not marked.
 //
+// The parent frame of a detected road marking is the virtual sensor coordinate
+// system.
+//
+// The virtual sensor coordinate system is relative to the vehicle coordinate
+// system which has its origin in the center of the rear axle of the ego
+// vehicle. This means if virtual sensor mounting position and orientation are
+// set to (0,0,0) the virtual sensor coordinate system coincides with the
+// vehicle coordinate system.
+//
 message DetectedRoadMarking
 {
     // Common information of one detected item.

osi_detectedtrafficlight.proto

@@ -13,6 +13,15 @@ package osi3;
 //
 // \image html OSI_DetectedTrafficLight.svg
 //
+// The parent frame of a detected traffic light is the virtual sensor coordinate
+// system.
+//
+// The virtual sensor coordinate system is relative to the vehicle coordinate
+// system which has its origin in the center of the rear axle of the ego
+// vehicle. This means if virtual sensor mounting position and orientation are
+// set to (0,0,0) the virtual sensor coordinate system coincides with the
+// vehicle coordinate system.
+//
 // One detected traffic light message defines a single 'bulb' and not a box of
 // several bulbs, e.g. red, yellow, green are three separate detected traffic
 // lights.

osi_detectedtrafficsign.proto

@@ -13,6 +13,15 @@ package osi3;
 //
 // \image html OSI_DetectedSign.svg
 //
+// The parent frame of a detected traffic sign is the virtual sensor coordinate
+// system.
+//
+// The virtual sensor coordinate system is relative to the vehicle coordinate
+// system which has its origin in the center of the rear axle of the ego
+// vehicle. This means if virtual sensoqr mounting position and orientation are
+// set to (0,0,0) the virtual sensor coordinate system coincides with the
+// vehicle coordinate system.
+//
 message DetectedTrafficSign
 {
     // Common information of one detected item.
@@ -45,11 +54,14 @@ message DetectedTrafficSign
         //
         // The orientation of the bounding box \c #base
         // ( \c BaseStationary::orientation ) is defined as follows:
+        //
         // The z-axis of the given \c BaseStationary::orientation is the vector
         // from the bottom to the top of the traffic sign's 2D image plate.
         // (Normally it is equal to the ground truth z-axis.)
+        //
         // The x-axis of the given \c BaseStationary::orientation is view
         // normal of the traffic sign's image.
+        //
         // This x-axis points from the traffic sign's image in the direction
         // from where a 'viewer' could see the traffic sign image.
         //