Hello everyone, I have two questions: 1. I'm almost done with the joint force sensors I mentioned a while ago and would like to submit them as patch, along with the necessary stuff to use the opaque interface of Player (arbitrary data). Unfortunately, my text editor has automatically stripped all trailing spaces in the files I modified along the way. Is there a diff tool (or an option to the standard diff) that can ignore these unimportant "changes"?
2. I am now tasked with the implementation of contact sensors as a step to constructing suction cups (for climbing bots). To access all necessary information about a contact, one has to call SetFeedback(dJointID, dJointFeedback) for the contact joint after it is created, but before it is evaluated. So, basically, in the collision callback of Gazebo. I am now wondering how to implement this with as little changes as possible. Here's what I think of: a. In the XML of a model, a contact sensor is a normal body that has the tag <provideContactFeedback> true </provideContactFeedback>. By adding a GetContactFeedback function to the Body class, a controller can acquire an array of dJointFeedback structs in which the first N contacts are to be found. b. In the collision callback, it is checked whether one of the connected bodies should provide contact feedback and if yes, SetFeedback is called for the created contact joint, with a pointer to the body's feedback array as second parameter. a is the easy part. As it might be difficult to find the right time to wipe the old data in the feedback array of the body (and I am not sure that there are multi-contact sensors currently in use) it might be better to save just one feedback, i.e. the one of the last contact joint created. b is somewhat of a problem. The collision callback knows only the ID of the body, not the body object it belongs to. So it's not possible to check whether this particular body should provide feedback about its contacts. And that's the question: Is there any way to get the body object of a given ID, or can you think of another feasible way to implement contact sensors? Ben ------------------------------------------------------------------------- This SF.net email is sponsored by the 2008 JavaOne(SM) Conference Don't miss this year's exciting event. There's still time to save $100. Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone _______________________________________________ Playerstage-gazebo mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/playerstage-gazebo
