Integrated Circulator for Regenerative Cryocoolers

The problem of cooling gimbaled optics and LWIR focal planes can be solved by placing the entire cryocooler on gimbal. However, a large mass penalty is paid for such configurations, because the gimbal itself must grow in size and mass in order to support the cryocooler. To address the requirements of cooling across a two-axis gimbal, flexible joint, or to multiple locations on a spacecraft, we propose to develop a lightweight, continuous-flow cooling loop integrated with a Pulse Tube Cryocooler (PTC). Because the cooling loop can be made of capillary tubing, it is easily made mechanically compliant by means of coiling thus allowing the cryocooler to be located off gimbal. Removing the cryocooler from the gimbal using the proposed Integrated Circulator (IC) will result in less mass on gimbal which in turn will provide for more agile (and capable) sensors, easier to integrate into spacecraft.