Default to new behavior, make the old one opt-in

CHANGELOG.md

@@ -5,9 +5,9 @@ The format of this document is based on [Keep a Changelog](https://keepachangelo
 
 ## [Unreleased]
 
-### Added
+### Changed
 
-- Added a new `useWorldReferenceOrientation` config option in the `gazebo_imu` plugin to take account for any initial non-zero orientation of the sensor as measured via `yarp::dev::IOrientationSensors` (https://github.com/robotology/gazebo-yarp-plugins/pull/639).
+- The `gazebo_imu` plugin used to output orientation measurements as if the sensor was zero-aligned with the world frame, regardless of the initial orientation of the part the sensor is attached to. To match most real-world IMUs, the default behavior was changed to allow measuring orientation with regard to the world frame at all times. The old behavior can be restored by setting the `useInitialSensorOrientationAsReference` config option (https://github.com/robotology/gazebo-yarp-plugins/pull/639).
 
 ### Fixed
 

plugins/imu/src/IMU.cc

@@ -152,8 +152,8 @@ void GazeboYarpIMU::Load(sensors::SensorPtr _sensor, sdf::ElementPtr _sdf)
                                           {"sensor_name", ::yarp::os::Value{_sensor->Name()}}
                                         };
 
-    if (m_parameters.check("useWorldReferenceOrientation")) {
-        imu_properties.put("useWorldReferenceOrientation", yarp::os::Value::getNullValue());
+    if (m_parameters.check("useInitialSensorOrientationAsReference")) {
+        imu_properties.put("useInitialSensorOrientationAsReference", yarp::os::Value::getNullValue());
     }
 
     //Open the driver

plugins/imu/src/IMUDriver.cpp

@@ -90,7 +90,7 @@ bool GazeboYarpIMUDriver::open(yarp::os::Searchable& config)
         return false;
     }
 
-    if (config.check("useWorldReferenceOrientation")) {
+    if (!config.check("useInitialSensorOrientationAsReference")) {
         m_parentSensor->SetWorldToReferenceOrientation(ignition::math::Quaterniond::Identity);
     }