Simulated encoder pulse output system and method
AssigneeRockwell Automation Technologies, Inc.
InventorsJuntao Quan, Adrian Wirth
Life of this patent
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Abstract
The invention includes a system and method for generating simulated encoder outputs in a control system. An output pulse width between reference position inputs is computed, the output pulse width being based upon a difference between an updated reference position input and a previous reference position input, and upon a time interval between the reference position inputs. Next, a plurality of simulated encoder pulses is output between updates of the reference position input based upon the computed output pulse width. The output pulse is thereafter adjusted in a closed loop manner between updates of the reference position input.
Claims25
A method for generating simulated encoder outputs in a control system comprising:
- computing an output pulse width between reference position inputs, the output pulse width being based upon a difference between an updated reference position input and a previous reference position input, and upon a time interval between the reference position inputs;
- outputting a plurality of simulated encoder pulses between updates of the reference position input based upon the computed output pulse width;
- and
- adjusting the output pulse width in a closed loop manner between updates of the reference position input.
A system for controlling a plurality of synchronized motors comprising:
- a primary motor drive comprising an incremental encoder configured to provide a plurality of digital position signals, the primary motor drive configured to provide a simulated encoder pulse output by calculating a plurality of pulse widths from the plurality of digital position signals;
- and
- at least one secondary motor drive.
A method for generating a simulated encoder output in a motor control system comprising:
- reading in a first reference position value corresponding to a first time value;
- reading in a second reference position value corresponding to a second time value;
- and
- determining an output pulse width based on a rate of change corresponding to a difference between the first reference position value and the second reference divided by a difference between the first time value and the second time value;
- and
- outputting a plurality of simulated encoder pulses with pulse width equal to the output pulse width.
A system for controlling a plurality of synchronized motors comprising:
- a master motor drive configured to provide a digital master encoder signal and to provide an incremental position pulse train signal based on the digital master encoder signal;
- at least one slave motor drive configured to receive the digital master encoder signal;
- and
- a process control element configured to receive the incremental position pulse train signal.
A method of simulating an incremental encoder pulse output comprising:
- receiving an initial digital incremental encoder reference position at an initial time;
- receiving an updated digital incremental encoder reference position at a time equal to one update interval after the initial time;
- interpolating an estimated incremental position based on a rate of change between the initial digital incremental encoder reference position and the updated digital incremental encoder reference position;
- computing an adjusted estimated incremental position by adding or subtracting a difference between the estimated incremental position and an incremental position indicated by a rising or falling edge of an incremental encoder output pulse;
- computing an output pulse width based on the adjusted estimated incremental position;
- and
- outputting the incremental encoder output pulse based on the output pulse width.
Dependencies are inferred from the claim text.