Multitrailer Vehicle Motion Control With Predictive Wheel Slip Limits
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing heavy-duty vehicle control systems fail to optimize handling, reduce energy consumption, and improve overall performance, particularly in multitrailer vehicles with self-powered dolly units, due to suboptimal wheel slip control and energy management.
Innovation Solution
A method for controlling heavy-duty vehicle motion using a predictive non-linear optimal control problem (NOCP) that constrains lateral and longitudinal wheel slips, combined with a control unit that manages energy distribution and actuator coordination based on wheel slip requests, optimizing vehicle maneuvers for safety and efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If traditional heavy-duty vehicle control systems are used, then the vehicle can operate with simple control mechanisms, but the handling performance and energy efficiency are suboptimal
Solution Approach 1:
The control system performs preliminary actions by predicting future wheel slip conditions and energy consumption patterns using a non-linear optimal control problem (NOCP) framework. The system calculates optimal wheel slip targets and energy distribution strategies in advance, allowing the vehicle to proactively adjust to upcoming maneuvers rather than reacting to current conditions alone.
Solution Approach 2:
The system implements dynamic control by continuously adjusting wheel slip targets and energy distribution based on real-time vehicle state and predicted maneuver requirements. The NOCP formulation allows dynamic optimization of control parameters such as lateral and longitudinal wheel slip limits, enabling the vehicle to adapt its handling characteristics and energy consumption patterns to varying operational conditions.
2Reliability
If wheel slip control is not optimized, then the control system is simpler to implement, but excessive wheel slip occurs reducing handling safety
Solution Approach 1:
The control system implements feedback mechanisms by continuously monitoring actual wheel slip conditions and comparing them against optimal targets derived from the NOCP formulation. The system uses this feedback to adjust control commands to wheel actuators, ensuring that wheel slip remains within safe limits while maintaining optimal handling performance. The feedback loop integrates with the predictive control framework to correct deviations from desired trajectories.
Solution Approach 2:
The system optimizes handling safety by dynamically changing control parameters such as lateral and longitudinal wheel slip limits based on vehicle state and predicted maneuvers. The NOCP formulation allows the system to adjust these parameters in real-time, optimizing the balance between maintaining traction and enabling necessary wheel slip for maneuvering, thereby preventing excessive wheel slip that would compromise safety.
3Use of energy by moving object
If energy management is not optimized, then the energy distribution system is simpler, but energy consumption increases reducing overall vehicle performance
Solution Approach 1:
The energy management system performs preliminary calculations to predict future energy consumption patterns based on predicted vehicle maneuvers and road conditions. The NOCP framework computes optimal energy distribution strategies in advance, allowing the system to proactively allocate energy resources to different vehicle functions and powertrain components, thereby minimizing overall energy consumption while maintaining required performance levels.
Solution Approach 2:
The system optimizes energy consumption by dynamically changing energy distribution parameters such as power allocation to electric machines, regenerative braking thresholds, and auxiliary power consumption based on predicted maneuver requirements. The NOCP formulation enables real-time adjustment of these parameters to match actual vehicle needs, reducing energy waste while maintaining optimal vehicle performance throughout the predicted maneuver sequence.
Data Source
AI summary
A method is disclosed for controlling motion of a heavy-duty vehicle. Information is obtained related to an upcoming vehicle path and vehicle maneuver along the path; and related to a road friction coefficient along the path. Lateral and longitudinal wheel slip limits are configured for at least two wheels of an axle or lumped group-axle on the vehicle. The lateral and longitudinal wheel slip values are related to respective lateral and longitudinal tyre force values via a pre-determined combined tyre slip model. A vehicle motion profile is determined for performing the vehicle maneuver as a solution to a non-linear optimal control problem (NOCP). The NOCP is constrained by the lateral and longitudinal wheel slip limits and formulated to account for the road friction coefficient and/or curvature along the upcoming vehicle path. Motion of the vehicle is controlled along the path based on the determined target vehicle motion profile.