{"action":"created","issue":{"url":"https://api.github.com/repos/cleanflight/cleanflight/issues/1110","labels_url":"https://api.github.com/repos/cleanflight/cleanflight/issues/1110/labels{/name}","comments_url":"https://api.github.com/repos/cleanflight/cleanflight/issues/1110/comments","events_url":"https://api.github.com/repos/cleanflight/cleanflight/issues/1110/events","html_url":"https://github.com/cleanflight/cleanflight/issues/1110","id":94245656,"number":1110,"title":"Derivative Kick","user":{"login":"borisbstyle","id":10757508,"avatar_url":"https://avatars.githubusercontent.com/u/10757508?v=3","gravatar_id":"","url":"https://api.github.com/users/borisbstyle","html_url":"https://github.com/borisbstyle","followers_url":"https://api.github.com/users/borisbstyle/followers","following_url":"https://api.github.com/users/borisbstyle/following{/other_user}","gists_url":"https://api.github.com/users/borisbstyle/gists{/gist_id}","starred_url":"https://api.github.com/users/borisbstyle/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/borisbstyle/subscriptions","organizations_url":"https://api.github.com/users/borisbstyle/orgs","repos_url":"https://api.github.com/users/borisbstyle/repos","events_url":"https://api.github.com/users/borisbstyle/events{/privacy}","received_events_url":"https://api.github.com/users/borisbstyle/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":10,"created_at":"2015-07-10T08:11:21Z","updated_at":"2015-07-11T06:30:21Z","closed_at":null,"body":"I opened this issue to continue discussing theories about preventing the \"Derivative Kick\" on RcCommand handling from some other PR's.\r\n\r\nThis is what we are talking about. Slower sampling of Rcdata is causing \"infinity\" in derivative. This is even filtered data, which smooths it out a bit already!\r\n![rccommand](https://cloud.githubusercontent.com/assets/10757508/8614616/91c3e51c-26eb-11e5-9fe4-b67cd425eb9f.jpg)\r\n\r\nThis is currently not an issue, rather than a cosmetical thing in my opinion. There are no negative effects in flight, but it would be neater to find a solution where we can smooth it out a bit even if it is preventing ramping a bit to prevent huge rises in D. We don't want to add too much delay preferably\r\n\r\nThere are some challenges in this one. Sampling of rcdata is pretty slow and is not done during each loop. The solution requires smarter sampling approach as the cycletimes are not constant. Too long sampling will cause much delay and too short sampling will still show ramping.\r\n\r\nAlso a question we should ask ourselves is. Do we want to solve this? After all it doesn't affect the flight performance and is pretty much filtered down the road (motor/esc).\r\n\r\nJust a random log from PID1:\r\nhttps://dl.dropboxusercontent.com/u/31537757/cleanflight/blackbox_many_flights.TXT"},"comment":{"url":"https://api.github.com/repos/cleanflight/cleanflight/issues/comments/120586847","html_url":"https://github.com/cleanflight/cleanflight/issues/1110#issuecomment-120586847","issue_url":"https://api.github.com/repos/cleanflight/cleanflight/issues/1110","id":120586847,"user":{"login":"ledvinap","id":2318015,"avatar_url":"https://avatars.githubusercontent.com/u/2318015?v=3","gravatar_id":"","url":"https://api.github.com/users/ledvinap","html_url":"https://github.com/ledvinap","followers_url":"https://api.github.com/users/ledvinap/followers","following_url":"https://api.github.com/users/ledvinap/following{/other_user}","gists_url":"https://api.github.com/users/ledvinap/gists{/gist_id}","starred_url":"https://api.github.com/users/ledvinap/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/ledvinap/subscriptions","organizations_url":"https://api.github.com/users/ledvinap/orgs","repos_url":"https://api.github.com/users/ledvinap/repos","events_url":"https://api.github.com/users/ledvinap/events{/privacy}","received_events_url":"https://api.github.com/users/ledvinap/received_events","type":"User","site_admin":false},"created_at":"2015-07-11T06:30:21Z","updated_at":"2015-07-11T06:30:21Z","body":"Maybe 10Hz, but filtering delay starts to get non-negligible (research would be necessary, quick googling:  in FPS games < 100ms is great, 200ms ok, 300ms almost unplayable).\r\n\r\nWhat about testing FIR (averaging) filter?"}}