Control accuracy of a pulse-operated electromechanical device

In an electric-operated control device comprising a control mechanism that is positioned by an electric control signal to control an output of the device and that has a frequency response characteristic which renders the control mechanism capable of tracking the fundamental frequency of the electric control signal whose fundamental frequency is less than a first frequency, and which renders the control mechanism incapable of tracking the fundamental frequency of the electric control signal whose fundamental frequency is greater than a second frequency which is sufficiently greater than the first frequency that, when applied in control of the control mechanism, positions the control mechanism to a position corresponding to a most recent time average of electric control signal, the control mechanism also functionally relating the output of the device to the electric control signal such that the output of the device as a function of the electric control signal consisting of time-averaged electric D.C. current flow comprises a first range wherein a given incremental change in time-averaged electric D.C. current flow causes an incremental change in output within a first range of incremental output changes and a second range wherein the same given incremental change in time-averaged electric D.C. current flow causes an incremental change in output within a second range of incremental output changes comprising incremental output changes that are substantially amplified from those of the first range of incremental output changes, a device for effectively attenuating the incremental output changes of the second range which comprises:

• a control, including a processor, for developing from a primary control signal and a secondary control signal, the electric control signal for controlling the control mechanism, the primary control signal including a pulse width modulated voltage waveform;
• wherein the processor causes the secondary control signal to selectively interact with the primary control signal in developing the electric control signal such that whenever the output is to be within the first range, the electric control signal is developed from the primary control signal alone, and whenever the output is to be within the second range, the electric control signal is developed by interaction of the secondary control signal with the primary control signal.

A system of an automotive vehicle comprising:

• an electric-operated device, including an electromechanical actuator, that controls an output of the system in accordance with an electric control signal comprising a waveform comprising voltage pulses applied to the actuator;
• and
• a control, including a processor, for developing the electric control signal from a primary control signal and a secondary control signal, the primary control signal including a pulse width modulated voltage waveform;
• wherein the processor causes the secondary control signal to selectively interact with the primary control signal in developing the electric control signal such that whenever the output is to be within a first range, the electric control signal is developed from the primary control signal alone, and whenever the output is to be within a second range, the electric control signal is developed by interaction of the secondary control signal with the primary control signal.

A control for controlling an output of a system of an automotive vehicle comprising:

• an electric-operated control device that controls the output of a system of an automotive vehicle in accordance with an electric control signal comprising a waveform comprising voltage pulses applied to the device;
• and
• an electric control, including a processor, for developing the electric control signal from a primary control signal and a secondary control signal, the primary control signal including a pulse width modulated voltage waveform;
• wherein the processor causes the secondary control signal to selectively interact with the primary control signal in developing the electric control signal such that at certain times, the electric control signal is developed from the primary control signal alone, and at certain other times, the electric control signal is developed by interaction of the secondary control signal with the primary control signal.