Simulation software helps design portable flight suit chiller unit

Ametek was contracted by Lockheed Martin to design a portable flight suit chiller unit for the Joint Strike Fighter (JSF) programme. This system works with a pilot cooling vest to maintain a pilot’s deep body core temperature at ≤ 100.4°F (38°C). The JSF programme aims to deliver affordable, next-generation striker aircraft weapon systems for the US Navy, Air Force, Marines and allies. Pilots flying these aircrafts are subject to high levels of acceleration – up to 9g – and must wear G-suits to prevent blackouts. To prevent pilots suffering from heat stress in the cockpit and on the ground, portable flight suit chiller units are needed.

Using Solidthinking Embed, the team created a working model of the combined chiller unit and control system via a block diagram approach. They correlated and refined the plant model using measurements of plant responses in the lab. Then a multi-loop PID controller was built with interlock safety stages that stepped through the start-up and shutdown actions necessary to avoid damage to sensitive device components.