Heavy-Duty Vehicle Sideslip Limits for Stable Motion Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Advanced motion management systems in heavy-duty vehicles face challenges in preventing excessive wheel slip, which can compromise safety and efficiency due to their complexity, particularly in maintaining vehicle stability and generating required forces during maneuvers.
Innovation Solution
A computer-implemented method in a vehicle control unit that determines dynamic wheel slip angle limits based on vehicle motion requests, allowing for MSD control allocation that balances longitudinal and lateral wheel slip, using a modified Hamiltonian algorithm and B-matrix control allocation to ensure safe and efficient vehicle motion, with dynamic limits that adjust according to target acceleration and curvature.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If a fixed dynamic slip limit with a large margin is configured to account for curvature, then vehicle stability is improved, but control freedom is reduced
Solution Approach 1:
The patent applies the dynamics principle by transitioning from a fixed slip limit to a dynamic slip limit that adapts in real-time based on vehicle state and motion requirements. The slip limit is continuously adjusted according to the difference between actual and target curvature, allowing the system to maintain stability when curvature deviation is large while maximizing control freedom when the vehicle is tracking the desired path accurately.
Solution Approach 2:
The patent implements parameter changes by modifying the slip limit parameter dynamically based on curvature error. The slip limit is calculated as a function of the difference between actual and target curvature, allowing the system to optimize the balance between stability and control freedom by adjusting this critical parameter in response to changing vehicle conditions.
2Reliability
If a dynamic slip limit configured in dependence of road friction condition is used, then safety margin is improved, but computation complexity increases
Solution Approach 1:
The patent applies parameter changes by dynamically adjusting the slip limit based on curvature error rather than relying on complex road friction condition modeling. This approach maintains safety margins through real-time adaptation to vehicle motion state while avoiding the computational burden of estimating road friction conditions and their impact on slip limits.
3Ease of operation
If wheel slip is limited to maintain linear wheel force vs wheel slip relationship, then control simplicity is improved, but force generation capability is reduced
Solution Approach 1:
The patent applies dynamics by making the slip limit adaptive rather than fixed. During normal operation, the slip limit maintains the linear relationship for control simplicity, but when curvature error exceeds the threshold, the system allows larger slip angles to maximize force generation capability for correcting the vehicle trajectory, thus dynamically balancing control simplicity with force generation needs.
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
A computer-implemented method performed in a vehicle control unit (130, 140) for controlling motion of a heavy-duty vehicle (100), the method comprising obtaining (S1) a vehicle motion request, wherein the vehicle motion request is indicative of a target curvature (creq) and a target acceleration (areq), determining (S2) a motion support device, MSD, control allocation (Ti/ λi/ ωi / δi) based on the vehicle motion request, determining (S3) a dynamic wheel slip angle limit (αlim) based on the vehicle motion request, where dynamic wheel slip angle limit (αlim) increases with a decreasing target acceleration (areq), and controlling (S4) the motion of the heavy-duty vehicle (100) based on the MSD control allocation constrained by the dynamic wheel slip angle limit (αlim).