{"action":"created","issue":{"url":"https://api.github.com/repos/betavr/steamvr_driver_hydra/issues/4","repository_url":"https://api.github.com/repos/betavr/steamvr_driver_hydra","labels_url":"https://api.github.com/repos/betavr/steamvr_driver_hydra/issues/4/labels{/name}","comments_url":"https://api.github.com/repos/betavr/steamvr_driver_hydra/issues/4/comments","events_url":"https://api.github.com/repos/betavr/steamvr_driver_hydra/issues/4/events","html_url":"https://github.com/betavr/steamvr_driver_hydra/issues/4","id":150266383,"number":4,"title":"Testing velocity and acceleration extrapolation.","user":{"login":"Relys","id":2224238,"avatar_url":"https://avatars.githubusercontent.com/u/2224238?v=3","gravatar_id":"","url":"https://api.github.com/users/Relys","html_url":"https://github.com/Relys","followers_url":"https://api.github.com/users/Relys/followers","following_url":"https://api.github.com/users/Relys/following{/other_user}","gists_url":"https://api.github.com/users/Relys/gists{/gist_id}","starred_url":"https://api.github.com/users/Relys/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/Relys/subscriptions","organizations_url":"https://api.github.com/users/Relys/orgs","repos_url":"https://api.github.com/users/Relys/repos","events_url":"https://api.github.com/users/Relys/events{/privacy}","received_events_url":"https://api.github.com/users/Relys/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/betavr/steamvr_driver_hydra/labels/enhancement","name":"enhancement","color":"84b6eb"}],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":3,"created_at":"2016-04-22T04:51:09Z","updated_at":"2016-04-27T22:13:13Z","closed_at":null,"body":"I spent a couple of hours messing around with extrapolation. Maybe you can get the values right? I was having issues with damping so I disabled the checks. I think the issue is that negative acceleration and velocity values represent the other side of an coordinate in 3D space so we need to account for that. As for accuracy maybe it would help to take a larger sample to calculate where the velocity and acceleration values converge? The sixense library has sixenseMath::Vector3 getVelocity(); sixenseMath::Vector3 getAcceleration(); functions which take current derivative but nothing for rotational and angular momentum so I am not using them. \r\n\r\nI also looked at the Unreal Hydra plugin for reference: https://github.com/getnamo/hydra-ue4/blob/master/Source/HydraPlugin/Private/FHydraPlugin.cpp#L441\r\n\r\nAnyways, here are my changes:\r\nhttps://github.com/Relys/driver_hydra/commit/a462252a2f1528b169883e67a3b135279f18f396"},"comment":{"url":"https://api.github.com/repos/betavr/steamvr_driver_hydra/issues/comments/215247574","html_url":"https://github.com/betavr/steamvr_driver_hydra/issues/4#issuecomment-215247574","issue_url":"https://api.github.com/repos/betavr/steamvr_driver_hydra/issues/4","id":215247574,"user":{"login":"betavr","id":9061447,"avatar_url":"https://avatars.githubusercontent.com/u/9061447?v=3","gravatar_id":"","url":"https://api.github.com/users/betavr","html_url":"https://github.com/betavr","followers_url":"https://api.github.com/users/betavr/followers","following_url":"https://api.github.com/users/betavr/following{/other_user}","gists_url":"https://api.github.com/users/betavr/gists{/gist_id}","starred_url":"https://api.github.com/users/betavr/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/betavr/subscriptions","organizations_url":"https://api.github.com/users/betavr/orgs","repos_url":"https://api.github.com/users/betavr/repos","events_url":"https://api.github.com/users/betavr/events{/privacy}","received_events_url":"https://api.github.com/users/betavr/received_events","type":"User","site_admin":false},"created_at":"2016-04-27T22:13:13Z","updated_at":"2016-04-27T22:13:13Z","body":"It won't be easy to feed the prediction engine with correct values. I'm thinking of using the 3 unused buttons on the hydra to enable ingame finetuning of the parameters, so we can find a usable setting more easily.\r\n\r\nAlso merged your changes in the f/imu_emulation branch, and made it switchable from settings."}}