{"action":"created","issue":{"url":"https://api.github.com/repos/PX4/Firmware/issues/3551","labels_url":"https://api.github.com/repos/PX4/Firmware/issues/3551/labels{/name}","comments_url":"https://api.github.com/repos/PX4/Firmware/issues/3551/comments","events_url":"https://api.github.com/repos/PX4/Firmware/issues/3551/events","html_url":"https://github.com/PX4/Firmware/issues/3551","id":127706960,"number":3551,"title":"Sensor data coordinate frame","user":{"login":"scott-eddy","id":5719830,"avatar_url":"https://avatars.githubusercontent.com/u/5719830?v=3","gravatar_id":"","url":"https://api.github.com/users/scott-eddy","html_url":"https://github.com/scott-eddy","followers_url":"https://api.github.com/users/scott-eddy/followers","following_url":"https://api.github.com/users/scott-eddy/following{/other_user}","gists_url":"https://api.github.com/users/scott-eddy/gists{/gist_id}","starred_url":"https://api.github.com/users/scott-eddy/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/scott-eddy/subscriptions","organizations_url":"https://api.github.com/users/scott-eddy/orgs","repos_url":"https://api.github.com/users/scott-eddy/repos","events_url":"https://api.github.com/users/scott-eddy/events{/privacy}","received_events_url":"https://api.github.com/users/scott-eddy/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":6,"created_at":"2016-01-20T15:28:25Z","updated_at":"2016-01-22T19:10:00Z","closed_at":null,"body":"All, I'm having some issues parsing frames associated with MAVLINK data.  Specifically, the HIGHRES_IMU message.  The HIGHRES_IMU MAVLINK message parses the sensor_combined uORB message into the proper fields.  Looking at the .msg specification for sensor_combined it says that the [accel data](https://github.com/PX4/Firmware/blob/master/msg/sensor_combined.msg#L38), gyro data, and mag data are expressed in the body NED frame.  \r\n\r\nHowever, the transformation applied to the data transforms it from the sensor frame to the body-fixed frame.  There is never an additional transformation from the body-fixed frame to the body NED frame.  Is the .msg comment wrong or is there another rotation applied elsewhere?"},"comment":{"url":"https://api.github.com/repos/PX4/Firmware/issues/comments/174014897","html_url":"https://github.com/PX4/Firmware/issues/3551#issuecomment-174014897","issue_url":"https://api.github.com/repos/PX4/Firmware/issues/3551","id":174014897,"user":{"login":"scott-eddy","id":5719830,"avatar_url":"https://avatars.githubusercontent.com/u/5719830?v=3","gravatar_id":"","url":"https://api.github.com/users/scott-eddy","html_url":"https://github.com/scott-eddy","followers_url":"https://api.github.com/users/scott-eddy/followers","following_url":"https://api.github.com/users/scott-eddy/following{/other_user}","gists_url":"https://api.github.com/users/scott-eddy/gists{/gist_id}","starred_url":"https://api.github.com/users/scott-eddy/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/scott-eddy/subscriptions","organizations_url":"https://api.github.com/users/scott-eddy/orgs","repos_url":"https://api.github.com/users/scott-eddy/repos","events_url":"https://api.github.com/users/scott-eddy/events{/privacy}","received_events_url":"https://api.github.com/users/scott-eddy/received_events","type":"User","site_admin":false},"created_at":"2016-01-22T19:10:00Z","updated_at":"2016-01-22T19:10:00Z","body":"@LorenzMeier @kd0aij The accelerations reported by the sensor_combined message are W.R.T a body-fixed frame with X-forward, Y-left, Z-up.  This is easily seen when looking at the Raw accelerations recorded by sdlog2 and noting that the Z acceleration is reported as -9.8 [m/s/s] implying a Z-UP frame.  **This body-fixed frame is not documented anywhere.**\r\n\r\nHowever, the gyro readings are W.R.T a frame with X-forward, Y-right, Z-Down.  Documentation should be updated.  "}}