[gene-h]

I wonder if there are any uses for mechanically modulated retroreflectors today. NASA is investigating fully mechanical rovers for Venus because semiconductors do not work very well at Venusian temperatures while mechanical devices do[0]. To get data back from a fully mechanical device they propose to use retroreflectors. Although the bandwidth they can achieve with their approaches, using semaphore messaging with retroreflectors and looking at the doppler shift provided by spinning disks, is low. Perhaps by using a device like the thing they could transmit data at acoustic rates. I am also curious if there are more down to earth applications for devices like the thing other than espionage. [0]https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/201700...