Aircraft Brake Force Estimation via Motor Current Sensing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current aircraft brake systems lack an efficient method to determine the braking force applied to the outer disc without using a force sensor, which is desirable for precise control and monitoring.

Innovation Solution

A system that includes a current sensor coupled to the actuator to detect the current applied and a controller to estimate the force based on predetermined input parameters, such as maximum force, maximum current, and efficiency fraction, determining the mode of operation and calculating the estimated force applied to the outer disc.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a force sensor is used to determine the braking force applied to the outer disc, then measurement precision is improved, but device complexity and cost increase

Engineering Contradiction:
Improvebraking force measurementVSAvoidsensor system
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent replaces the mechanical force sensor system with an electrical measurement system. The motor controller measures electrical parameters (current, voltage, power) that are inherently available during motor operation, and uses these to calculate the braking force through control algorithms. This substitution eliminates the need for separate force sensors while maintaining measurement capability.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The motor controller uses its own existing measurement capabilities (current and voltage sensing) to determine the braking force. The system serves itself by utilizing data already collected for motor control purposes, rather than requiring external force measurement devices. The control algorithm processes this self-generated data to provide force information.

Inventive Principle:
Principle #25Self-service

2Measurement precision

If a force sensor is installed in the actuator system, then force detection accuracy is improved, but ease of operation and system simplicity deteriorate

Engineering Contradiction:
Improveforce detectionVSAvoidsystem operation
Core Design Contradiction:
Measurement precisionVSEase of operation

Solution Approach 1:

The motor controller performs multiple functions: it controls the motor operation, monitors electrical parameters, and calculates braking force. This multi-functional approach means the same device that manages motor control also provides force measurement, eliminating the need for separate force sensing hardware and simplifying system operation.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent merges the force measurement function with the existing motor control system. The current and voltage sensing circuits, already present for motor control, are also used for braking force calculation. This consolidation reduces the number of separate components and simplifies the overall system architecture.

Inventive Principle:
Principle #5Merging (Combining)

3Device complexity

If electrical parameters are used to estimate force instead of force sensors, then device complexity is reduced, but measurement precision may deteriorate

Engineering Contradiction:
Improvesensor systemVSAvoidforce estimation
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The motor controller continuously monitors electrical parameters (current, voltage, power) and uses this feedback to calculate and estimate the braking force. The control system processes this real-time electrical data through algorithms that account for the relationship between electrical input and mechanical output, providing accurate force estimation without direct mechanical measurement.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent changes the measurement parameter from direct mechanical force to electrical parameters (current, voltage, power). By measuring electrical quantities that are directly related to the motor's mechanical output through known physical relationships, the system achieves force estimation accuracy while avoiding the complexity of force sensors. The control algorithm transforms electrical parameter data into meaningful force information.

Inventive Principle:
Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Enables accurate estimation of the braking force applied to the aircraft brake's outer disc without the need for a force sensor, ensuring precise control and monitoring of the braking process.

Implementation Method 1

A motor converts electrical energy into mechanical energy that causes the force to be applied to the outer disc using an actuator

Methodology Applied
Scientific EffectElectromagnetic conversion: Electromagnetic Induction

Implementation Method 2

A current sensor coupled to the actuator is configured to detect a detected amount of current applied to the actuator

Methodology Applied
Scientific EffectElectrical current detection: Ohm's Law

Implementation Method 3

When forced together, friction reduces the angular speed of the rotating discs

Methodology Applied
Scientific EffectFriction: Friction

Data Source

PatentEP3032234B1Open loop load force estimation systems and methods
Publication Date: 2020.05.06 GOODRICH CORP
  • EP3032234B1 patent drawingFigure 1
  • EP3032234B1 patent drawingFigure 2
  • EP3032234B1 patent drawingFigure 3A~3B

AI summary

What is described is a system for determining a force applied to an outer disc of an aircraft brake by an actuator motor (206). The system includes a current sensor (208) coupled to the actuator motor (206) and configured to detect an amount of current applied to the actuator motor (206). The system also includes a controller coupled to the current sensor (208). The controller is configured to determine an estimate of the force applied to the outer disc based on the detected amount of current and predetermined input parameters.