Digital multiplex servo control

Claim 1

Apparatus for digitally controlling an actuator for an airfoil or the like in an aircraft, comprising: first means for sampling the value of the controlled variable at a particular rate; an arithmetic unit with accumulator and additional storage facilities; digital multiplexing means having input and output respectively connected to output and input of said unit for handling the digital data flow from and to said unit; program-controlled means providing control signals for operating the multiplexing means for obtaining data transfer through the unit and for processing data held in the storage facility and for storing the processed data in the storage facility, the control means further providing control signals for operating the multiplexing means for feeding said sampled values to the unit, the multiplexing means having its input connected to the first means; a storage means holding signals representing particular modifiers including particular reference and command signals provided in response to rising and descend commands when received as inputs, the storage means further including coefficient, determining the transfer characteristics of the control operation, the multiplexing means having its input connected to the storage means, the control means operating the multiplexing means for transfer of signals to the unit; the control means providing control signals to the arithmetic unit for causing the arithmetic unit to compose output control signals from the signals in the storage means and from the sampled values including the calculation of error signals and of correction signals in accordance with the coefficients stored in the storage means; and output means for providing output control signals to the plant and having its input connecteD to the output of the multiplexing means, the control means operating the multiplexing means to feed output signals to the output means.