Adaptive Cruise Control Speed Transition Logic

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional distance-related vehicle speed control systems fail to adapt seamlessly to driver intervention and changing road conditions, potentially leading to unsafe situations when the driver deactivates distance control, especially on winding roads or when the vehicle ahead maintains a lower speed.

Innovation Solution

The system allows for the deactivation of distance control, switching to current vehicle speed as the desired speed, with an advisory signal for the driver and automatic reactivation under specific conditions, ensuring safe following and maintaining the system's functionality.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If the distance control is deactivated during following drive, then the driver can manually override the system to adapt to specific road conditions or driving preferences, but the vehicle may drive into the target object if the target object continues at the same speed, creating a safety hazard

Engineering Contradiction:
Improvedriver's ability to override distance controlVSAvoidcollision avoidance capability
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The control device continuously monitors the actual distance to the target object and compares it with the desired distance. When distance control is deactivated and the vehicle speed exceeds the target object's speed, the system provides feedback by preventing acceleration commands that would reduce the distance below a safety threshold, thereby maintaining collision avoidance capability even when distance control is deactivated.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The system dynamically adjusts its behavior based on the activation state of distance control. When distance control is deactivated, the system transitions from maintaining a fixed distance to allowing speed variations, but retains safety constraints by limiting acceleration when the vehicle speed is higher than the target object's speed and the actual distance is approaching the desired distance.

Inventive Principle:
Principle #15Dynamics

2Speed

If the distance control is deactivated and the vehicle speed is higher than the target object's speed, then the vehicle can accelerate further to overtake, but the distance to the target object decreases, potentially leading to unsafe following distance

Engineering Contradiction:
Improvevehicle acceleration capabilityVSAvoiddistance to target object
Core Design Contradiction:
SpeedVSLength of moving object

Solution Approach 1:

The control device continuously monitors both the vehicle speed and the actual distance to the target object. When distance control is deactivated and the vehicle speed exceeds the target object's speed, the system provides feedback by preventing acceleration commands that would reduce the distance below a safety threshold, thereby maintaining safe following distance while allowing speed increases within safe limits.

Inventive Principle:
Principle #23Feedback

3Stability of the object's composition

If the distance-related vehicle speed control system carries out speed control to the previously specified desired speed after deactivation, then the system maintains consistent control behavior, but it may not adapt to the current driving conditions and driver intentions

Engineering Contradiction:
Improvecontrol system consistencyVSAvoidadaptation to current driving conditions
Core Design Contradiction:
Stability of the object's compositionVSAdaptability or versatility

Solution Approach 1:

The system dynamically adjusts its reference speed based on the activation state of distance control. When distance control is deactivated, the desired speed is updated to the current vehicle speed rather than maintaining the previously specified desired speed, allowing the system to adapt to current driving conditions while maintaining stable control behavior through consistent update rules.

Inventive Principle:
Principle #15Dynamics

Data Source

PatentEP1924461B1Inter-vehicle-distance-related cruise control system
Publication Date: 2011.04.13 BAYERISCHE MOTOREN WERKE AG

AI summary

The invention relates to an inter-vehicle-distance-related cruise control system for a motor vehicle which, when the motor vehicle is travelling on a clear section of road, adjusts the velocity to a predefined desired velocity, and when a vehicle is following a vehicle travelling in front carries out inter-vehicle distance control to a predefined distance from the vehicle travelling in front, it being possible to deactivate the inter-vehicle distance controller. According to the invention, after the inter-vehicle distance controller has been deactivated while the vehicle is following another vehicle the inter-vehicle-distance-related cruise control system does not control the velocity to the previously predefined velocity of the motor vehicle, but rather to the velocity which was current at the time of the deactivation of the inter-vehicle distance controller, as a desired velocity.