Dynamometer Steering Force Simulation via External Actuation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Dynamometer testing systems face challenges in accurately simulating real-life driving conditions, particularly for vehicles with complex transmissions and driver assistance systems, due to differences in torque and force when using dynamometer test units instead of actual wheels, which can hinder the testing of systems that rely on steering angle changes.

Innovation Solution

A method and system where a controllable dynamometer power source is used to apply torque to a wheel shaft, with an external force influencing the dynamometer test unit to mimic the force required for steering angle changes, allowing for accurate simulation of real-life steering resistance by adjusting the force based on vehicle speed and steering angle changes, using linear actuators or other force-applying mechanisms.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a dynamometer test unit is rigidly connected to the wheel hub to enable torque application, then torque measurement capability is improved, but the force required for steering angle changes becomes unrealistic compared to real-life driving conditions

Engineering Contradiction:
Improvetorque measurement capabilityVSAvoidsteering angle change realism
Core Design Contradiction:
Measurement precisionVSEase of operation

Solution Approach 1:

A force applying means is introduced as an intermediary element between the dynamometer test unit and the external environment. This mediator applies external forces to the dynamometer test unit during steering angle changes, simulating real-life road conditions and compensating for the unrealistic high forces that would otherwise be required to rotate the heavy test unit.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Stability of the object's composition

If the dynamometer test unit is made heavy to provide stable torque application, then torque control stability is improved, but the force required to change steering angle increases excessively

Engineering Contradiction:
Improvetorque control stabilityVSAvoidforce required for steering angle changes
Core Design Contradiction:
Stability of the object's compositionVSForce

Solution Approach 1:

The force applying means acts as a counterbalancing mechanism that applies external forces to offset the excessive forces generated by the heavy dynamometer test unit during steering maneuvers. This allows the system to maintain stable torque control while compensating for the unrealistic steering forces.

Inventive Principle:
Principle #8Anti-weight (Counterweight)

3Device complexity

If the dynamometer test unit structure is simplified for ease of connection, then device complexity is reduced, but the ability to simulate real-life driving forces is compromised

Engineering Contradiction:
Improvedynamometer test unit structureVSAvoidsimulation accuracy
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The system is segmented into distinct functional components: the dynamometer test unit for torque application and measurement, and the separate force applying means for simulating real-life driving forces. This segmentation allows each component to be optimized independently while working together to achieve both structural simplicity and simulation accuracy.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP3635360B1Method and system for use in dynamometer testing of a motor vehicle
Publication Date: 2022.10.19 ROTOTEST INT
  • EP3635360B1 patent drawingFigure 1
  • EP3635360B1 patent drawingFigure 2A
  • EP3635360B1 patent drawingFigure 2B

AI summary

The present invention relates to a method for use in dynamometer testing of a vehicle (100) having a steering mechanism for changing steering angle of at a wheel hub (203) connected to a first wheel shaft, the method including: - in use, applying a torque to said first wheel shaft using a first controllable dynamometer power source (201) of a vehicle dynamometer test unit (110, 111) rigidly connected to said wheel hub (203), - wherein a change of steering angle of said wheel hub (203) rotates said rigidly connected first dynamometer test unit (110, 111), characterized in the method including, when changing steering angle of said wheel hub (203): - applying an external force acting on the dynamometer test unit (110, 111) to influence force required by the vehicle steering mechanism to change steering angle of said wheel hub (203).