Magnetorheological Damper Control for Low-Speed Rattle Suppression

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing damper devices with magnetorheological fluid-based dampers can exhibit undesirable 'scratching' or 'rattling' feedback during low-load compression, leading to a perceived lack of responsiveness and resonance, especially at low speeds, which is not adequately addressed by increasing measurement frequency or filtering.

Innovation Solution

A method for controlling the damper device that involves recording and analyzing measurement data sets for speed and acceleration signals, selecting appropriate filter parameter sets based on signal magnitude, and using these to derive control data sets for adjusting the damping force in real-time, ensuring a fast and smooth response across varying load conditions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If measurement frequency is increased to improve response speed, then responsiveness is improved, but noise and instability increase causing scratching feedback

Engineering Contradiction:
Improveresponse speedVSAvoidsignal stability
Core Design Contradiction:
SpeedVSMeasurement precision

Solution Approach 1:

The filter parameters are dynamically adjusted based on the current operating conditions (compression speed, acceleration). When compression speed is low, stronger filtering is applied to reduce noise. When compression speed is high, weaker filtering is applied to maintain fast response. This dynamic adaptation resolves the contradiction between response speed and signal stability.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The filter parameters (cutoff frequency, filtering strength) are changed based on the magnitude of speed and acceleration signals. By adapting the filtering parameters to the current signal characteristics, the system achieves both fast response when needed and noise reduction when compression is slow, eliminating the scratching feedback while maintaining responsiveness.

Inventive Principle:
Principle #35Parameter changes

2Measurement precision

If filtering is strengthened to reduce noise, then signal stability is improved, but response delay increases reducing responsiveness

Engineering Contradiction:
Improvesignal stabilityVSAvoidresponse delay
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The filter parameters are dynamically adjusted based on the current operating conditions (compression speed, acceleration). When compression speed is low, stronger filtering is applied to reduce noise. When compression speed is high, weaker filtering is applied to maintain fast response. This dynamic adaptation resolves the contradiction between response speed and signal stability.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The filter parameters (cutoff frequency, filtering strength) are changed based on the magnitude of speed and acceleration signals. By adapting the filtering parameters to the current signal characteristics, the system achieves both fast response when needed and noise reduction when compression is slow, eliminating the scratching feedback while maintaining responsiveness.

Inventive Principle:
Principle #35Parameter changes

3Force

If damping force is increased to improve damping performance, then damping effectiveness is improved, but smoothness decreases causing rattling feedback

Engineering Contradiction:
Improvedamping forceVSAvoiddamping smoothness
Core Design Contradiction:
ForceVSStability of the object's composition

Solution Approach 1:

The damping force is dynamically adjusted based on the current operating conditions (compression speed, acceleration). When compression speed is low, stronger filtering is applied to reduce noise. When compression speed is high, weaker filtering is applied to maintain fast response. This dynamic adaptation resolves the contradiction between response speed and signal stability.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The filter parameters (cutoff frequency, filtering strength) are changed based on the magnitude of speed and acceleration signals. By adapting the filtering parameters to the current signal characteristics, the system achieves both fast response when needed and noise reduction when compression is slow, eliminating the scratching feedback while maintaining responsiveness.

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

This approach enables a damper device with improved responsiveness and damping behavior, reducing resonance and 'scratching' feedback by adapting filtering intensity based on signal magnitude, thus providing optimal damping properties in all situations.

Implementation Method 1

The damping valve has a damping channel with a magnetorheological fluid. A magnetic field generating device is assigned to the damping valve and is used to generate and control a magnetic field. This influences a type of opening state of the damping valve.

Methodology Applied
Scientific EffectMagnetorheological effect: Magnetorheological Fluid

Data Source

PatentEP3298300B1Method for controlling a damper device
Publication Date: 2022.09.14 INVENTUS ENG
  • EP3298300B1 patent drawingFigure 1~2
  • EP3298300B1 patent drawingFigure 3~7
  • EP3298300B1 patent drawingFigure 8

AI summary

A damper device (100) and method for controlling the damping of a relative movement of two connection units (101, 102) that can move relative to one another, a controllable damper (1) comprising a damping valve (8) with a magnetorheological fluid being provided between the connection units in order to damp the relative movement. A magnetic field generation device (11) is associated with the damping valve (8) in order to generate and control a magnetic field. Measurement data records (90, 91) relating to a relative movement of the connection units (101, 102) to one another are detected and processed using a filter device (80). A data record (92, 93) derived from the detected measurement data record (90, 91) is stored in a memory device (45). The derived data record (92, 93) comprises a speed signal (28) and an acceleration signal (29) for the relative movement of the connection units (101, 102). The stored data record (92, 93) is analyzed and a filter parameter record (82, 83) is determined in accordance with the result of the analysis. For low-value speed signals (28) and acceleration signals (29), the control device (46) selects a filter parameter record with a higher degree of filtering and for higher-value speed signals (28) or acceleration signals (29) a filter parameter record with a lower degree of filtering. The filter parameter record (82, 83) is used to derive a control data record (94, 95) from the measurement data record (90, 91). The control data record (94, 95) is used to control the damper device (100).