Wheel Torque Control Using Drive Shaft Speed Variation Estimation

Solution Overview

Problem

Existing systems take too long to effectively control wheel slip, leading to vehicle instability and reduced traction due to mismatched wheel and vehicle speeds.

Innovation Solution

A computer system estimates the variation in rotational speed of a drive shaft using angles and ride height to accurately determine a target slip for a wheel, adjusting torque applied to the wheel to quickly reduce slip.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional torque compensation is applied to control wheel slip, then vehicle stability and traction are improved, but the response time is too slow to optimally control stability and traction

Engineering Contradiction:

Improvevehicle stabilityVSAvoidresponse time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The system performs preliminary action by estimating the variation in rotational speed of the drive shaft in advance, based on the angles and ride height, before the wheel slip control is activated. This allows the target slip to be pre-calculated with accurate compensation for drive shaft speed variations, enabling faster response when torque adjustment is needed without sacrificing stability control quality

Inventive Principle:

Principle #10Preliminary action

2Reliability

If conventional torque compensation is applied to control wheel slip, then vehicle traction is improved, but the response time is too slow to optimally control stability and traction

Engineering Contradiction:

Improvevehicle tractionVSAvoidresponse time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The system performs preliminary action by estimating the variation in rotational speed of the drive shaft in advance, based on the angles and ride height, before the wheel slip control is activated. This allows the target slip to be pre-calculated with accurate compensation for drive shaft speed variations, enabling faster response when torque adjustment is needed without sacrificing traction control quality

Inventive Principle:

Principle #10Preliminary action

Data Source

PatentEP4385839B1Adjusting a torque applied to a wheel of a vehicle

Publication Date: 2026.03.18 VOLVO TRUCK CORP

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AI summary

A computer system (700) comprising a processor device (702) configured to adjust a torque applies to a first wheel (15) to a vehicle (1) is provided. The processor device (702) is configured to estimate, a variation in rotational speed of a first drive shaft (13). The first drive shaft (13) is driven by a second drive shaft (23) by rotating a mechanical joint (5). The mechanical joint (5) is drivingly connected to both the first drive shaft (13) and the second drive shaft (23). The processor device (702) is configured to, based on the variation in rotational speed of the first drive shaft (13) and a current speed of the vehicle (1), estimate a target slip for the first wheel (15). The processor device (702) is further configured to, based on the estimated target slip for the first wheel (15), adjust the torque applied to the first wheel (15).