Decentralized H2 optimal control of haptic interfaces for a shared virtual environment

Decentralized control of haptic interface devices for a shared virtual environment over delayed communication is considered. We show that allowing indirect communication between the interface devices via the virtual environment site may greatly facilitate controller synthesis and analysis by rendering the problem quadratically invariant. In particular, this allows us to find an insightful structure possessed by all stabilizing controllers within the proposed architecture and to show that this structure offers stability of the system regardless the delay length. We show also that within the proposed control architecture, the global H² optimization can be reduced to a number of uncoupled model matching problems with multiplicative delays.