Traction Control via Rolling Radius Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current traction systems for heavy road vehicles fail to accurately adjust wheel slip due to the assumption that the rolling radius of traction wheels remains constant, leading to non-optimal traction and undesired wheel slip, especially when driving conditions change.
Innovation Solution
A traction system comprising a mechanical propulsion system and a hydraulic propulsion system, with a control unit that measures and adjusts the rolling radii of both systems to optimize traction by calculating the present relation between the rolling radii of the wheels, allowing for real-time adjustments based on changing conditions such as tire pressure and load.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If the rolling radius of traction wheels is assumed to be constant, then the system structure is simple, but wheel slip control becomes inaccurate
Solution Approach 1:
The system dynamically changes the parameter of rolling radius from a constant assumed value to a variable that is continuously measured by sensors. The control unit receives actual rolling radius data from sensors and adjusts traction control based on these changing parameters, resolving the contradiction between system simplicity and control accuracy.
Solution Approach 2:
The system implements feedback by using sensors to continuously measure the actual rolling radius of traction wheels and feeding this information back to the control unit. The control unit then adjusts the traction control accordingly, creating a closed-loop system that maintains accurate wheel slip control despite variations in rolling radius.
2Measurement precision
If sensors are added to measure rolling radius, then wheel slip control accuracy improves, but device complexity increases
Solution Approach 1:
The system uses the vehicle's existing motion and wheel rotation data to determine rolling radius variations. By utilizing already-available sensor data from the vehicle's normal operation (wheel speed, distance traveled), the system derives rolling radius information without requiring dedicated rolling radius sensors, thus improving accuracy while minimizing additional complexity.
Solution Approach 2:
The control unit performs multiple functions: it not only controls traction but also calculates rolling radius from existing sensor data. This multi-functionality allows the system to achieve accurate wheel slip control using existing components, reducing the need for additional specialized sensors and minimizing system complexity.
Data Source
AI summary
In a method for controlling a traction system for a heavy road vehicle, the system includes a first mechanical propulsion system, a second hydraulic propulsion system, and a control unit. The method includes measuring a first parameter value, indicative of the rolling radius of a first traction wheel, measuring a second parameter value, indicative of the rolling radius of a second traction wheel, and the control unit using the first and second parameter values for determining a present relation between the rolling radii of the first and second traction wheels. The control unit provides an output signal based on the present relation to optimize the traction applied to the second traction wheel. A traction system and a heavy vehicle incorporating a traction system are also provided.