Back to results
US 10,895,866 B1Granted
Position error correction for electric motors
AssigneeApple Inc.
InventorsBon Ho Bae, Jihoon Jang
Life of this patent
Estimating the term…
Abstract
Position and speed correction are applied to observed values from a position sensor in order to operate an electric motor. Observed position values and observed speed values are obtained from the position sensor for time points during a sampling window, ideal position values and ideal speed values are determined for each of the time points, and position and speed error values are determined based on the observed and ideal values. Stored position information is updated using the position error values and the speed error values. The electric motor is operated using corrected position values and corrected speed values that are determined from the observed position values, the observed speed values, and the stored position information.
Claims20
An apparatus, comprising:
- a position sensor that outputs observed position values for time points during a sampling window, wherein observed speed values are determined based on the observed position values;
- an electric motor that is connected to the position sensor and is operated according to corrected position values and corrected speed values that are determined based on the observed position values, the observed speed values, and stored position information;
- and
- a position corrector that is operable to:
- determine ideal speed values for each of the time points based on the observed speed values and according to a speed model that describes a change in a speed of the electric motor during the sampling window;
- determine ideal position values for each of the time points based on the ideal speed values,
- determine position error values for each of the time points based on the observed position values and the ideal position values,
- determine speed error values for each of the time points based on the observed speed values and the ideal speed values, and
- update the stored position information using the position error values and the speed error values.
6 more elements
An apparatus, comprising:
- a position sensor that outputs observed position values for time points during a sampling window, wherein observed speed values are determined based on the observed position values;
- an electric motor that is connected to the position sensor;
- and
- a position corrector that is operable to:
- determine ideal position values and ideal speed values for each of the time points, wherein the ideal position values and the ideal speed values for each of the time points are estimated by assuming a linearly changing speed during the sampling window,
- determine position error values for each of the time points based on the observed position values and the ideal position values,
- determine speed error values for each of the time points based on the observed speed values and the ideal speed values,
- update stored position information using the position error values and the speed error values, and
- operate the electric motor using corrected position values and corrected speed values that are determined from the observed position values, the observed speed values, and the stored position information.
6 more elements
A method, comprising:
- obtaining observed position values from a position sensor for time points during a sampling window, wherein observed speed values are determined based on the observed position values;
- determining ideal speed values for each of the time points based on the observed speed values and according to a speed model that describes a change in a speed of the electric motor during the sampling window;
- determining ideal position values for each of the time points based on the ideal speed values;
- determining position error values for each of the time points based on the observed position values and the ideal position values;
- determining speed error values for each of the time points based on the observed speed values and the ideal speed values;
- updating stored position information using the position error values and the speed error values;
- and
- operating an electric motor according to corrected position values and corrected speed values that are determined based on the observed position values, the observed speed values, and the stored position information.
5 more elements
A system, comprising:
- a computing device having computer-executable instructions that, when executed, cause the computing device to:
- obtain observed position values from a position sensor for time points during a sampling window, wherein observed speed values are determined based on the observed position values,
- determine ideal speed values for each of the time points based on the observed speed values and according to a speed model that describes a change in a speed of the electric motor during the sampling window;
- determine ideal position values for each of the time points based on the ideal speed values,
- determine position error values for each of the time points based on the observed position values and the ideal position values,
- determine speed error values for each of the time points based on the observed speed values and the ideal speed values,
- update stored position information using the position error values and the speed error values, and
- operate an electric motor according to corrected position values and corrected speed values that are determined from the observed position values, the observed speed values, and the stored position information.
5 more elements
Dependencies are inferred from the claim text.