RFID Dose Tracking Mechanism for Battery-Free Injection Devices
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing drug delivery devices lack an efficient and cost-effective method to track the amount of medicament delivered, requiring internal power sources for dose detection and transmission.
Innovation Solution
A drug delivery device with an RFID chip that modulates its resonance frequency based on the position of components during dose setting and dispensing operations, using passive or active RFID technology to transmit dose information wirelessly without an internal power source.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If passive RFID technology is used for dose tracking, then cost is reduced and device complexity is minimized, but the ability to actively transmit dose information is limited
Solution Approach 1:
The patent replaces active electronic transmission systems with passive RFID technology that uses electromagnetic fields for communication. The RFID tag modulates the RFID signal's resonance frequency to encode dose information, eliminating the need for internal power sources and active transmission components while maintaining information transfer capability.
Solution Approach 2:
The patent changes the resonance frequency parameter of the RFID tag's antenna circuit based on the dose delivered. As the plunger moves during dose dispensing, it alters the antenna's electrical characteristics (capacitance/inductance), which modulates the resonance frequency. This frequency modulation encodes the dose information that can be read by an external RFID reader.
2Loss of information
If internal power sources are used for dose detection and transmission, then active dose information transmission is enabled, but device complexity and cost increase
Solution Approach 1:
The RFID tag system is powered by the electromagnetic field generated by the external RFID reader, eliminating the need for an internal power source. The tag's antenna harvests energy from the reader's signal to power its circuit and modulate the response signal, making the system self-sufficient without batteries or power management components.
Solution Approach 2:
The patent uses the external RFID reader as an intermediary to provide both power and communication functionality. The reader's electromagnetic field serves as both the power source for the passive tag and the communication channel for transmitting dose information, consolidating multiple functions into a single external device.
3Measurement precision
If resonance frequency modulation is used to track dose, then accurate dose tracking is achieved, but the RFID circuit design becomes more complex
Solution Approach 1:
The patent combines the dose tracking mechanism with the RFID tag's existing antenna circuit. The plunger rod's movement, which is already part of the insulin pen's mechanical dose delivery system, directly modifies the antenna's electrical characteristics. This integration eliminates the need for separate sensing components and reduces overall system complexity.
Solution Approach 2:
The RFID tag's antenna circuit serves multiple functions: it acts as the communication interface for RFID signaling and simultaneously functions as the sensing element for dose tracking. The same circuit that enables wireless communication also provides the resonance frequency modulation that encodes dose information, making the system multi-functional without adding components.
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
Enables accurate tracking of delivered doses and device information, facilitating central monitoring and patient adherence, while being cost-effective and requiring minimal device modifications.
Implementation Method 1
when the RFID chip is in the reach of a reader device such as a smart phone with an RFID reader, the antenna receives a signal from the smart phone and sends a wireless response signal
Implementation Method 2
the resonance frequency of the RFID's device changes and this change indicates the change in position of the component
Data Source
AI summary
Described is a dose tracking mechanism for a drug delivery device, including a moveable component configured to move with respect to a housing during operation of the drug delivery device and an RFID device with an electric circuit having a resonance frequency. The electric circuit includes an antenna configured to transmit a wireless RFID signal at the resonance frequency and an electrical component operatively coupled to the moveable component and configured to modify the resonance frequency based on a position of the moveable component, such that the resonance frequency of the electric circuit is an indication of the position of the moveable component. In some instances, the position of the moveable component indicates a dose set or dispensed from the drug delivery device.