Automated Parking Brake Touch Point Detection via Linear Extrapolation

Solution Overview

Problem

Current methods for determining the touch point of an automated parking brake are complex and slow, especially at high voltages, due to non-linear current profiles, leading to late detection of the inflection point and requiring significant computational resources.

Innovation Solution

A method that estimates the touch point using simple computational rules through linear extrapolation of variables describing the release process, allowing for early calculation and precise positioning of the brake piston, without the need for additional sensors.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If complex calculation formulas are used to determine the inflection point, then measurement precision is improved, but computing time increases and productivity decreases

Engineering Contradiction:

Improvetouch point detection accuracyVSAvoidcomputing speed

Core Design Contradiction:

Measurement precisionVSProductivity

Solution Approach 1:

The release process is divided into distinct phases: a first phase before the inflection point and a second phase after the inflection point. By segmenting the process and identifying characteristic points (inflection point) that separate these phases, the system can determine the touch point more efficiently without requiring complex continuous calculations throughout the entire release process.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The control unit determines the inflection point in advance during the release process, before the parking brake is fully released. This preliminary determination allows the system to know when the touch point has been reached and adjust the release process accordingly, avoiding the need for complex post-processing calculations.

Inventive Principle:

Principle #10Preliminary action

2Measurement precision

If complex calculation formulas are used to determine the inflection point, then measurement precision is improved, but device complexity increases

Engineering Contradiction:

Improvetouch point detection accuracyVSAvoidcomputational complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The release process is divided into distinct phases: a first phase before the inflection point and a second phase after the inflection point. By segmenting the process and identifying characteristic points (inflection point) that separate these phases, the system can determine the touch point more efficiently without requiring complex continuous calculations throughout the entire release process.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The control unit continuously monitors release variables during the release process and uses this feedback to detect the inflection point. When the inflection point is detected, the control unit responds by adjusting the release process (e.g., reversing the actuator). This feedback-based approach simplifies the overall system by using real-time monitoring rather than complex pre-computed formulas.

Inventive Principle:

Principle #23Feedback

3Reliability

If the release process continues until complete elimination of clamping force, then reliability is improved, but loss of time increases

Engineering Contradiction:

Improvebrake release completenessVSAvoidrelease time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The control unit determines the inflection point in advance during the release process, before the parking brake is fully released. This preliminary determination allows the system to know when the touch point has been reached and adjust the release process accordingly, avoiding the need for complex post-processing calculations.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The control unit continuously monitors release variables during the release process and uses this feedback to detect the inflection point. When the inflection point is detected, the control unit responds by adjusting the release process (e.g., reversing the actuator). This feedback-based approach simplifies the overall system by using real-time monitoring rather than complex pre-computed formulas.

Inventive Principle:

Principle #23Feedback

Data Source

PatentUS11639159B2Method and device for operating an automated parking brake

Publication Date: 2023.05.02 ROBERT BOSCH GMBH

AI summary

Disclosed is a method for operating an automated parking brake for a motor vehicle comprising at least one braking mechanism with a brake piston. In said method, the parking brake moves the brake piston by means of an actuator between an idle position, in which the brake piston applies no braking moment, and a braking position, in which the brake piston applies a braking moment, in relation to a brake disk, and during a disengagement process of the parking brake, a reference point is determined in which the brake piston is located in a position in which it applies substantially no braking moment and which is between its idle position and its braking position. The method according to the disclosure is characterized in that the reference point is estimated taking into account an extrapolation of a variable describing the disengagement process.