Power Steering Oscillation Compensation Algorithm
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing power steering systems experience steering wheel oscillations due to vehicle imbalances, which degrade driving comfort and can cause resonance at specific frequencies, and current solutions only partially reduce these oscillations while risking destabilization of the main control algorithm.
Innovation Solution
A method for controlling the assistance motor in power steering systems that includes a compensation algorithm within the steering computer, which determines a compensation motor torque to oppose the torque induced by imbalances, ensuring the steering wheel torque equals a reference torque, thereby suppressing oscillations without interfering with the main control algorithm.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If motor torque is amplified at oscillation frequency to counter imbalance movements, then steering wheel oscillation amplitude is reduced, but the main control algorithm may be destabilized
Solution Approach 1:
The control system is segmented into two independent algorithms: the main control algorithm for normal steering assistance and a separate oscillation compensation algorithm for suppressing imbalance-induced vibrations. This segmentation allows each algorithm to operate independently with its own stability characteristics, preventing the compensation actions from destabilizing the main control system while still achieving oscillation reduction.
Solution Approach 2:
An intermediary oscillation compensation algorithm acts as a mediator between the imbalance disturbances and the main control algorithm. This intermediary processes the steering wheel torque signal, identifies oscillation components, and generates compensating torque specifically targeted at oscillation frequencies, thereby protecting the main control algorithm from direct exposure to destabilizing oscillation counteractions.
2Object-affected harmful factors
If existing oscillation reduction solutions are integrated into the main control algorithm, then steering wheel oscillation amplitude is decreased, but complete elimination is not achieved and algorithm stability is compromised
Solution Approach 1:
By separating the oscillation compensation function from the main control algorithm into an independent parallel algorithm, the system achieves complete oscillation elimination without compromising stability. The segmented architecture allows the compensation algorithm to focus exclusively on oscillation suppression with aggressive control actions, while the main algorithm maintains overall system stability.
Solution Approach 2:
The oscillation compensation algorithm applies excessive action specifically targeted at oscillation frequencies by amplifying motor torque precisely at these frequencies. This partial action concentrated on the harmful frequency range enables complete oscillation elimination without requiring excessive control effort across the entire frequency spectrum, thereby achieving precision without sacrificing stability.
Data Source
AI summary
A method controls a power steering motor of a power steering system. The power steering system includes at least one steering wheel configured to receive a steering torque applied by a driver, the power steering motor being configured to apply a motor torque to a rack, at least one wheel connected to the rack, and at least one steering computer implementing a main control algorithm. The main control algorithm includes a step of determining a main engine torque according to at least the steering wheel torque, characterised in that the steering computer also includes an algorithm for compensating for an oscillation of the steering wheel implementing a step of determining a compensating engine torque such that the steering wheel torque is equal to a reference steering wheel torque.