Infant Carrier Detection via Seat Belt Spool Rotation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing child mode detection systems in automobiles are prone to errors due to reliance on weight, pressure, or tension sensors, which are inaccurate when the vehicle is in motion, posing a safety risk to infant passengers.
Innovation Solution
A method and system that detect the presence of an infant carrier by measuring the unwound length of a seat belt, deactivating the airbag, and modifying the speed limit, using a navigation system to ensure safe driving conditions by limiting speed and acceleration, and guiding the driver through safer routes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If weight, pressure, or tension sensors are used to detect infant presence, then the detection system is simple to implement, but the measurement precision deteriorates when the vehicle is in motion
Solution Approach 1:
The patent replaces mechanical sensors (weight, pressure, tension sensors) with a spool rotation detection system that measures the length of seat belt unwound. This substitution eliminates the sensitivity to vehicle motion that plagues mechanical sensors, as the spool rotation measurement remains accurate regardless of vehicle acceleration or vibration.
Solution Approach 2:
The patent introduces an intermediary measurement approach by measuring the spool rotation and unwound seat belt length as an intermediate parameter, then using this to infer infant presence. This intermediary measurement is less directly affected by vehicle motion than direct weight or pressure measurements, thereby improving detection accuracy.
2Reliability
If child mode is activated to ensure infant safety, then passenger safety is improved, but driving performance deteriorates due to speed and acceleration limitations
Solution Approach 1:
The patent makes the speed limitation dynamic rather than static. The system monitors the vehicle's current speed and compares it against a predetermined threshold associated with child mode. When the threshold is exceeded, the system activates child mode and applies braking force. This dynamic approach allows the vehicle to maintain higher speeds when safe, while automatically enforcing speed limitations only when necessary, thus balancing safety with driving performance.
3Measurement precision
If the spool rotation detection system is used to detect infant carrier, then the measurement precision is improved, but the device complexity increases
Solution Approach 1:
The patent leverages the spool mechanism that already exists in the seat belt system for its primary function of restraining passengers. By adding sensors to detect spool rotation, the system repurposes this existing mechanical component for a secondary function of infant presence detection. This multi-functionality approach improves detection accuracy without adding entirely new mechanical systems, thereby limiting the increase in overall device complexity.
Solution Approach 2:
The spool mechanism serves itself by providing detection information through its own rotation. The existing spool, designed to unwind and rewind the seat belt, naturally records the length of belt deployed through its rotation. By sensing this rotation, the system allows the spool to provide both its original function (seat belt deployment) and the additional function (infant detection reference) without requiring a separate dedicated detection mechanism.
Data Source
Figure 1~2
AI summary
A method of activating a child mode in an automobile (200) is provided. The method comprises determining the presence of an infant carrier (101) on a seat (102) of the automobile (200). This involves detecting that a seat belt (103) associated with the seat (102) has been unwound from an associated spool by an amount that is greater than a threshold amount. In response thereto, the child mode is activated in the automobile (200).