Method and device for determining a measure of quality continuously

Patent metadata

Field	Value
Publication number	US-11726470-B2
Application number	US-202117447858-A
Country	US
Kind code	B2
Filing date	Sep 16, 2021
Priority date	Oct 26, 2020
Publication date	Aug 15, 2023
Grant date	Aug 15, 2023

Abstract

A method of continuously determining a measure of quality for a control device of a technical device or for a system model of a technical system, from an input variable and an output variable. Time series of the input variable and the output variable are acquired up to a time step. A discrete ARMAX model structure is adapted for the ascertained, corresponding time series of the input variable and output variable, in order to determine a first set of parameters for modeling the time series of the input variable and a second set of parameters for modeling the time series of the output variable. The measure of quality is determined for the time step as a function of the first and the second set of parameters.

First claim

What is claimed is:

1. A method for continuously adapting a control device of a technical device during operation of the technical device, the method comprising:
acquiring a time series of an input variable, wherein the time series of the input variable includes a plurality of values of the input variable up to a time step and wherein the input variable is a setpoint which the control device operates the technical device to attain using a control function;
acquiring a time series of an output variable, wherein the time series of the output variable includes a plurality of values of the output variable up to the time step and wherein the output variable is an actual state which the technical device produces due to operation by the control device using the control function;
using a discrete Autoregressive Moving Average Model with Exogenous Inputs (ARMAX) model structure for the ascertained time series of the input variable and the ascertained time series of the output variable to determine a first set of parameters for modeling the time series of the input variable and a second set of parameters for modeling the time series of the output variable; and
based on a quality for the time step, as indicated by the first and the second sets of parameters, automatically modifying the control function, thereby modifying the operation of the technical device to produce different values of the output variable for respective values of the input variable.

2. The method as recited in claim 1 , wherein the ARMAX model structure includes a transfer function, which corresponds to a second-order delay element.

3. The method as recited in claim 1 , wherein the first and second sets of parameters are ascertained, assuming a noise level of 0.

4. The method as recited in claim 1 , wherein model parameters including a gain, a time constant, and a damping coefficient, are determined from the first and the second sets of parameters, and wherein the quality, upon which the automatic modification is based, is as indicated by the model parameters.

5. The method as recited in claim 4 , wherein the quality, upon which the automatic modification is based, is as indicated by a difference of the damping coefficient from a value of 1.

6. The method as recited in claim 4 , wherein the quality, upon which the automatic modification is based, is as indicated by a difference of the time constant from a predefined setpoint value.

7. The method as recited in claim 1 , wherein a measure of the quality is ascertained continuously in consecutive time steps, and a fault of the control device, based on which the control function is modified, is detected as a function of a value of the measure of the quality or of a temporal change in the measure of the quality.

8. The method as recited in claim 1 , wherein:
a modeled system variable of a system model is selected as the input variable and a measured system variable is selected as the output variable;
model parameters of the system model, including a time constant and a damping coefficient, are determined from the first and second sets of parameters, and
a measure of the quality is determined from the model parameters.

9. The method as recited in claim 8 , wherein the system model is adapted as a function of the measure of the quality.

10. A method for continuously adapting a control device of a technical device during operation of the technical device, the method comprising:
acquiring a time series of an input variable and a time series of an output variable up to a time step;
adapting a discrete Autoregressive Moving Average Model with Exogenous Inputs (ARMAX) model structure for the ascertained time series of the input variable and the ascertained time series of the output variable, to determine a first set of parameters for modeling the time series of the input variable and a second set of parameters for modeling the time series of the output variable; and
based on a measure of a quality for the time step determined as a function of a first difference between a sum of the parameters of the first set of parameters and a sum of the parameters of the second set of parameters, automatically modifying the control device, thereby modifying operation of the technical device to produce different values of the output variable for respective values of the input variable.

11. The method as recited in claim 10 , wherein the measure of quality is a function of a difference of the first difference from a comparison variable, which corresponds to a second difference of the sum of the parameters of the first set of parameters and the sum of parameters of the second set of parameters in an adjusted state.

12. A system comprising:
a control unit;
a control device; and
a technical device;
wherein, during operation of the technical device, the control unit is configured to:
acquire a time series of an input variable, wherein the time series of the input variable includes a plurality of values of the input variable up to a time step and wherein the input variable is a setpoint which the control device operates the technical device to attain using a control function;
acquire a time series of an output variable, wherein the time series of the output variable includes a plurality of values of the output variable up to the time step and wherein the output variable is an actual state which the technical device produces due to operation by the control device using the control function;
use a discrete Autoregressive Moving Average Model with Exogenous Inputs (ARMAX) model structure for the time series of the input variable and the time series of the output variable to determine a first set of parameters for modeling the time series of the input variable and a second set of parameters for modeling the time series of the output variable; and
based on a quality for the time step, as indicated by the first and the second sets of parameters, automatically modify the control function, thereby modifying the operation of the technical device to produce different values of the output variable for respective values of the input variable.

13. A non-transitory machine-readable storage medium on which is stored a computer program that is executable by a processor, and that, when executed by the processor, causes the processor to perform a method for continuously adapting a control device of a technical device during operation of the technical device, the method comprising:
acquiring a time series of an input variable, wherein the time series of the input variable includes a plurality of values of the input variable up to a time step and wherein the input variable is a setpoint which the control device operates the technical device to attain using a control function;
acquiring a time series of an output variable, wherein the time series of the output variable includes a plurality of values of the output variable up to the time step and wherein the output variable is an actual state which the technical device produces due to operation by the control device using the control function;
using a discrete Autoregressive Moving Average Model with Exogenous Inputs (ARMAX) model structure for the ascertained time series of the input variable and the ascertained time series of the output variable to determine a first set of parameters for modeling the time series of the input variable and a second set of parameters for modeling the time series of the output variable; and
based on a quality for the time step, as indicated by the first and the second sets of parameters, automatically modifying the control function, thereby modifying the operation of the technical device to produce differen

Assignees

• Bosch Gmbh Robert

Inventors

• Bleile Thomas
• Hoepfner Christina
• Huck Rene

Classifications

• G05B23/0294 Primary

  Optimizing process, e.g. process efficiency, product quality · CPC title

• G05B13/042 Primary

  in which a parameter or coefficient is automatically adjusted to optimise the performance · CPC title

• G01B3/10 Primary

  Measuring tapes · CPC title

• G05B23/0254

  based on a quantitative model, e.g. mathematical relationships between inputs and outputs; functions: observer, Kalman filter, residual calculation, Neural Networks · CPC title

• G05B23/02

  Electric testing or monitoring · CPC title