KVH Industries of Middletown, R.I., has received a production order from Raytheon Integrated Defense Systems of Tewksbury, Mass., for its new fiber optic-based inertial measurement unit. Raytheon plans to use a variant of KVH's TG-6000 unit as part of the guidance system in the US Navy's Mark 54 torpedoes, the next-generation antisubmarine warfare weapon. The unit, which employs military-grade fiber optic gyros, offers higher performance and lower cost than the technology currently integrated in torpedoes. It measures motion and acceleration in three dimensions, a tool considered critical in torpedo navigation. Delivery of a limited production volume is planned in January.