{"action":"opened","issue":{"url":"https://api.github.com/repos/bulletphysics/bullet3/issues/1904","repository_url":"https://api.github.com/repos/bulletphysics/bullet3","labels_url":"https://api.github.com/repos/bulletphysics/bullet3/issues/1904/labels{/name}","comments_url":"https://api.github.com/repos/bulletphysics/bullet3/issues/1904/comments","events_url":"https://api.github.com/repos/bulletphysics/bullet3/issues/1904/events","html_url":"https://github.com/bulletphysics/bullet3/issues/1904","id":364963997,"node_id":"MDU6SXNzdWUzNjQ5NjM5OTc=","number":1904,"title":"0 mean motor commands results in significant drift over time","user":{"login":"Olimoyo","id":14180933,"node_id":"MDQ6VXNlcjE0MTgwOTMz","avatar_url":"https://avatars2.githubusercontent.com/u/14180933?v=4","gravatar_id":"","url":"https://api.github.com/users/Olimoyo","html_url":"https://github.com/Olimoyo","followers_url":"https://api.github.com/users/Olimoyo/followers","following_url":"https://api.github.com/users/Olimoyo/following{/other_user}","gists_url":"https://api.github.com/users/Olimoyo/gists{/gist_id}","starred_url":"https://api.github.com/users/Olimoyo/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/Olimoyo/subscriptions","organizations_url":"https://api.github.com/users/Olimoyo/orgs","repos_url":"https://api.github.com/users/Olimoyo/repos","events_url":"https://api.github.com/users/Olimoyo/events{/privacy}","received_events_url":"https://api.github.com/users/Olimoyo/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"assignees":[],"milestone":null,"comments":0,"created_at":"2018-09-28T16:45:05Z","updated_at":"2018-09-28T16:45:05Z","closed_at":null,"author_association":"NONE","body":" Hi,\r\n\r\nI am trying to reproduce the 2D reacher experiment using pybullet. As a quick test, I am sending random 0 mean actions:\r\n```bash\r\n        agent.applyAction(action=np.array([0, np.random.uniform(-1,1), np.random.uniform(-1,1),0,0,0]), type=\"velocity\")\r\n```\r\nOver time it seems that the position of the joints drift away from 0. As shown by the pictures below:\r\n\r\nInitial position:\r\n![initial2](https://user-images.githubusercontent.com/14180933/46221587-bd2a4f00-c31b-11e8-810c-57508b9790e7.png)\r\n\r\nPosition after a while:\r\n![final2](https://user-images.githubusercontent.com/14180933/46221586-bd2a4f00-c31b-11e8-9c89-7b678e70d647.png)\r\n\r\nI made sure to turn off gravity and I'm sending velocity commands.\r\n\r\nDoes anyone have any idea why this might be happening or how to prevent this?\r\n\r\nThanks!"}}
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