On Thu, Feb 2, 2012 at 8:06 AM, Thomas Moulard wrote: > On Mon, Jan 23, 2012 at 4:06 PM, Jack O'Quin wrote: >> REP-0103 says: >> >>  "In relation to a body the standard is: x forward, y left, z up". >> >> While "up" may seem arbitrary for a gripper, "forward" suggests the >> direction to which it is extended. > > Sorry for the delay. > What would be your proposition, removing the scheme and just adding that > the frames is oriented as X toward the object and Y the object main axis? Definitely, X toward the object. I propose Y to be the main dimension in which the "fingers" of the gripper move. Some hand-like or claw-like devices may not fit that notion very well, but it can probably be defined in a way that is at least understandable. Z would be the remaining dimension, orthogonal to X and Y. --  joq