A gravity measuring device, mounted in an airplane. Specifically a gravity gradiometer. The isolation platform was needed to isolate the device from the plane's

A gravity measuring device, mounted in an airplane. Specifically a gravity gradiometer. The isolation platform was needed to isolate the device from the plane's movement to the greatest degree possible, as while we were doing a differential measurement, the common mode error was still significant enough that a very high degree of mechanical isolation was necessary. An _exceptionally_ hard problem... unfortunately the company eventually went bankrupt a few years after I left, having never quite managing to ship a commercially viable product.