Vehicle Steering Control Apparatus Speed-Adaptive Rate Variator
Solution Overview
Problem
Existing vehicle steering control systems experience degraded control responsiveness and stability when transitioning from low-speed to high-speed ranges, leading to difficulties in precise control.
Innovation Solution
A vehicle steering control apparatus that includes a target course setter, first and second control quantity calculators, a control rate variator, and a steering controller, which adjusts the rates of control quantities based on vehicle speed to maintain stable and precise control across varying speed ranges by using a combination of feedforward and feedback controls.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If control parameters are optimized for medium- or high-speed ranges, then steering characteristics are improved at those speeds, but control responsiveness deteriorates in low-speed range
Solution Approach 1:
The patent applies dynamics by making the control parameters variable rather than fixed. The control rate variator dynamically adjusts the first and second control rates based on the detected vehicle speed, allowing the control system to adapt its characteristics to match the current operating speed range. This resolves the contradiction by enabling optimal responsiveness at each speed without sacrificing adaptability across the full speed range.
Solution Approach 2:
The patent changes the control parameters (first control rate and second control rate) based on vehicle speed. By detecting the vehicle speed and selecting appropriate control rates from predetermined sets, the system transforms a static control system into a variable one that maintains optimal performance across different speed ranges, thereby resolving the contradiction between speed-optimized characteristics and broad adaptability.
2Speed
If control parameters are optimized for low-speed range, then control responsiveness is improved at low speeds, but steering characteristics deteriorate in medium- or high-speed range
Solution Approach 1:
The control rate variator dynamically selects appropriate control rates based on vehicle speed, ensuring that the system maintains reliable and stable control characteristics at each speed range. This dynamic adaptation prevents the deterioration of control stability at medium- or high-speeds while preserving low-speed responsiveness, thereby resolving the contradiction between low-speed responsiveness and overall control reliability.
Solution Approach 2:
By changing the control parameters (control rates) according to vehicle speed, the system ensures that appropriate parameters are used for each operating condition. This parameter adaptation maintains control stability across all speed ranges while preserving responsiveness where needed, resolving the contradiction between low-speed responsiveness and medium-/high-speed stability.
3Device complexity
If a single control rate is used across all speed ranges, then device complexity is reduced, but control precision deteriorates when transitioning between speed ranges
Solution Approach 1:
The control rate variator introduces dynamic parameter selection without significantly increasing system complexity. By using a speed detection mechanism and predetermined control rate sets, the system achieves variable control precision across speed ranges while maintaining relatively simple device architecture. This resolves the contradiction by enabling precise control during speed transitions through dynamic parameter adaptation.
Solution Approach 2:
The system changes control parameters based on detected vehicle speed, selecting from predetermined first and second control rates. This parameter adaptation enables precise control during speed range transitions while keeping the device complexity manageable through the use of speed-based parameter selection. The contradiction is resolved by achieving precision through intelligent parameter management rather than complex control algorithms.
Data Source
AI summary
A vehicle steering control apparatus includes a target course setter, a first control quantity calculator, a second control quantity calculator, a control rate variator, and a steering controller. The target course setter sets, based on forward environment information, a target course to be traveled by an own vehicle. The first control quantity calculator calculates a first control quantity that allows the own vehicle to travel along the target course. The second control quantity calculator calculates a second control quantity based on a steering angle. The control rate variator variably sets, in accordance with a vehicle speed, a first rate of the first control quantity and a second rate of the second control quantity. The steering controller calculates a steering control quantity, based on the first control quantity corrected based on the first rate and the second control quantity corrected based on the second rate, and executes a steering control.