Vehicle Security System With Passive Secondary Key
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Solution Overview
Problem
Smart key fobs used for vehicle entry and ignition are bulky, costly, and prone to loss or damage, leading to potential theft and inconvenience, as they require encrypted communication and reprogramming, making them undesirable for situations where carrying them is inconvenient or risky.
Innovation Solution
A secondary key system that is passive, compact, and waterproof, allowing the primary key to be temporarily disabled or reactivated for secure vehicle access and ignition control, with the secondary key being unable to activate the ignition and only operable for locking and unlocking doors, thus providing an additional layer of security and convenience.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a smart key fob is used for vehicle entry and ignition, then secure access and engine control are achieved, but the device becomes bulky, expensive, and prone to loss or damage
Solution Approach 1:
The invention divides the key system into two separate keys: a primary key (smart key fob) with full functionality for ignition and access, and a secondary key with limited functionality for access only. This segmentation allows users to carry only the secondary key when ignition functionality is not needed, reducing the burden of carrying a bulky smart key fob while maintaining security through the primary key when required
Solution Approach 2:
The secondary key creates a simplified copy of the primary key's access functionality without replicating its full capabilities. The secondary key contains a transponder that communicates with the vehicle's control system to enable door access, but lacks the ignition activation capability of the primary key, thus providing a lightweight, inexpensive alternative for situations where only entry is needed
2Ease of operation
If a smart key fob is carried on person, then convenient access is available, but risk of loss, damage, or theft increases
Solution Approach 1:
By separating access functionality from ignition functionality into two distinct keys, the system allows users to carry only the robust, simple secondary key during activities where loss or damage would be problematic (such as water sports or manual labor), while the primary key remains secure at home or in a safe location
Solution Approach 2:
The secondary key is designed as a simpler, more durable device that can be replaced more easily and cheaply than the primary key if lost or damaged. This allows users to treat the secondary key as a disposable or replaceable item for high-risk situations, while the expensive primary key with ignition capability remains protected
3Reliability
If primary key functionality is disabled when locked inside vehicle, then security against unauthorized use is improved, but user convenience may be reduced
Solution Approach 1:
The system performs preliminary detection to determine whether the primary key is inside or outside the vehicle before disabling its functionality. If the primary key is detected inside the locked vehicle, the system disables it to prevent unauthorized use. When the vehicle is subsequently unlocked with the secondary key, the system re-enables the primary key, ensuring user convenience is restored
Solution Approach 2:
The control system continuously monitors the presence of the primary key and the state of the locking system, providing feedback to dynamically adjust the primary key's functionality. This feedback mechanism ensures that the primary key is disabled only when necessary (inside locked vehicle) and re-enabled when appropriate (after unlocking), balancing security requirements with user convenience
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
The secondary key system enhances security by allowing the primary key to be rendered dormant within the vehicle, preventing unauthorized use, while being more compact and cost-effective, and providing a convenient alternative for situations where the primary key is not needed, such as during leisure activities or in wet environments.
Implementation Method 1
the secondary key is a passive transponder or a passive transceiver device operable to activate and deactivate the locking system
Data Source
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AI summary
A security system and security devices, optionally for a vehicle. The security system comprising a control unit, a locking system, a primary key and a secondary key, the primary key and the secondary key each normally operable to activate and deactivate the locking system and upon operation of the secondary key to activate the locking system, at least some or all of the functionality of the primary key is caused to be disabled and/or the control unit is caused to temporarily ignore command signals transmitted by the primary key.