Vehicle Control Device Tilt Threshold Adaptation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vehicle control devices struggle to accurately prevent rolling backwards on inclined road surfaces during automatic engine stop and restart, as they fail to precisely detect road gradients, leading to insufficient suppression of rolling and increased fuel consumption.
Innovation Solution
A vehicle control device that includes means for detecting vehicle tilt and forcibly restarting the engine when the tilt exceeds a predetermined value during deceleration, allowing for automatic stopping during relatively relaxed conditions on inclined surfaces while preventing rolling.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If automatic stopping of the engine is prohibited during deceleration on roads with large upward gradients, then rolling backwards of the vehicle is prevented, but fuel consumption increases and mileage deteriorates
Solution Approach 1:
The system dynamically changes the tilt determination value parameter based on vehicle operating conditions. During deceleration, a first (lower) determination value is used, allowing automatic stopping on mild gradients. During acceleration or at other times, a second (higher) determination value is used, preventing stopping on steeper gradients. This parameter adaptation resolves the contradiction by enabling fuel-saving automatic stops when safe and preventing rolling backwards when necessary.
2Reliability
If the automatic stopping process is strictly limited during deceleration, then rolling backwards is suppressed, but the frequency of automatic stopping is reduced and fuel consumption is not sufficiently suppressed
Solution Approach 1:
The system changes the tilt threshold parameter based on the vehicle's acceleration state. During deceleration, a lower threshold (first determination value) is applied, permitting automatic stopping more frequently. During acceleration or normal operation, a higher threshold (second determination value) is applied, restricting automatic stopping to prevent rolling backwards. This resolves the contradiction by adapting the stopping criteria to match the vehicle's dynamic state.
Solution Approach 2:
The control system dynamically adjusts the automatic stopping permission based on real-time detection of acceleration or deceleration states. The tilt determination value is not fixed but changes according to the vehicle's motion state, enabling the system to be more permissive during deceleration (allowing frequent stops) and more restrictive during acceleration (preventing rolling backwards).
3Use of energy by moving object
If the tilt determination value is set high to allow automatic stopping during deceleration, then fuel consumption is reduced, but rolling backwards occurs on gradient road surfaces
Solution Approach 1:
The system uses two different tilt determination values: a first (lower) value during deceleration that allows automatic stopping on mild gradients, and a second (higher) value during acceleration or other states that prevents stopping on steeper gradients. This dual-parameter approach resolves the contradiction by matching the threshold to the vehicle's operational context.
4Measurement precision
If the detected tilt value is corrected based on acceleration, then precision of gradient detection is improved, but device complexity increases
Solution Approach 1:
The system replaces complex continuous correction calculations with a simpler conditional approach. Instead of continuously correcting tilt values based on acceleration data, the system detects acceleration states and selects from two predetermined tilt determination values. This substitution of a complex correction mechanism with a simpler conditional selection process maintains measurement precision while reducing device complexity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Ensures frequent automatic engine stopping during deceleration while effectively suppressing rolling backwards on gradient surfaces, maintaining vehicle stability and reducing fuel consumption.
Implementation Method 1
means for detecting a tilt, which detects a tilt value indicative of a tilt of the vehicle in a longitudinal direction thereof
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention provides a vehicle control device having an advantage of ensuring frequency of automatic stopping of an engine during deceleration of a vehicle while suppressing reliably rolling backwards of the vehicle even if a road surface has a gradient. The means for controlling automatic stopping 22C performs an automatic stopping process of an engine 10 when a stop condition during stopping is established in a stopping state of a vehicle, or when a stop condition during deceleration is established in a decelerating state of the vehicle. The means for controlling automatic restart 22D performs an automatic restart process of the engine 10 when a restart condition is established in a state where the engine 10 is in the automatic stopping process. The tilt sensor 38 detects a tilt value θ indicative of a tilt of the vehicle in a longitudinal direction thereof. The means for forced restarting 22E forcibly performs the automatic restart process in a state where the tilt value θ is greater than a determining tilt value θc for the decelerating state when the vehicle is in a stopping state or a low speed state just before the stopping state following the performing of the automatic stopping process, in the decelerating state of the vehicle.