US Patent:
20120215351, Aug 23, 2012
Inventors:
H. Dean McGee - Rochester Hills MI, US
Tien L. Chang - Troy MI, US
Peter Swanson - Lake Orion MI, US
Jianming Tao - Troy MI, US
Di Xiao - Rochester Hills MI, US
Ho Cheung Wong - Troy MI, US
Jason Tsai - Bloomfield Hills MI, US
International Classification:
G05B 19/418
Abstract:
A system and method for controlling avoiding collisions and deadlocks in a workcell containing multiple robots automatically determines the potential deadlock conditions and identifies a way to avoid these conditions. Deadlock conditions are eliminated by determining the deadlock-free motion statements prior to execution of the motions that have potential deadlock conditions. This determination of deadlock-free motion statements can be done offline, outside normal execution, or it can be done during normal production execution. If there is sufficient CPU processing time available, the determination during normal production execution provides the most flexibility to respond to dynamic conditions such as changes in I/O timing or the timing of external events or sequences. For minimal CPU impact the determination is done offline where many permutations of programming sequences can be analyzed and an optimized sequence of execution may be found.