Arrangement for converting polar coordinate servo actuating signals into rectangular coordinate actuating signals

Claim 1

An arrangement for use in follow-up systems and the like, operative for accepting an input error signal having a magnitude indicative of the angular deviation of a polar-coordinate controlled variable from a reference angle and converting such input error signal into two rectangular-coordinate actuating signals having proportional-plus-integral characteristics, comprising, in combination, generator means for generating first and second periodic waveforms of identical predetermined frequency f1 phase-shifted relative to each other by 90*; switch means connected to the output of said generator means and oPerative when triggered for momentarily permitting transmission of the instantaneous values of said periodic waveforms; comparator means having an output, a first input and a second input and operative for triggering said switch means when equal signals are applied to said first and second inputs of said comparator means; frequency-transducer means having an output connected to said first input of said comparator means and having an input, and operative for producing an additional periodic waveform whose frequency departs from f1/n, n being an integer, in dependence upon the magnitude of the signal applied to the input of said frequency-transducer means and whose frequency is equal to f1/n when the magnitude of the signal applied to said input of said frequency-transducer means is zero; and means for applying an error signal to said second input of said comparator means and also to said input of said frequency-transducer means.