Independent Flight Termination Link for UAS Fly-Away Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Unmanned aerial systems (UAS) pose a safety risk due to 'fly away' events, where malfunctions cause them to fly uncontrollably, and existing solutions like GPS geo-fences and kill switches are inadequate, as they either fail to disable the UAS in time or rely on primary radio links that can be lost or interrupted.
Innovation Solution
A flight termination system comprising a ground-based transmitter and airborne receiver with a dedicated radio link, independent of the UAS's primary operation link, that allows for remote termination of the UAS's propulsion system through a three-step process involving arming, standby, and termination modes, with bi-directional confirmation to prevent erroneous operation and hacking.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If GPS based geo-fences are implemented to disable the UAS when it flies outside of pre-defined airspace, then the UAS can be restricted to safe areas, but the UAS cannot be disabled in time as it arrives at the airspace boundary traveling so fast that it lands/crashes outside the defined airspace zone
Solution Approach 1:
The flight termination system is pre-configured with geo-fence boundaries and armed before flight. When the UAS approaches the boundary, the system has already been prepared to immediately disable propulsion, eliminating the time delay associated with detecting boundary violation and then activating the kill switch. The system waits in a ready state to act instantly when the trigger condition is met.
2Reliability
If kill switch functionality is implemented through the primary radio control link, then the operator can disable the UAS in case of fly away, but the operator will not be able to activate the kill switch if the primary radio link is lost or interrupted
Solution Approach 1:
A separate, dedicated radio link serves as an intermediary communication channel between the ground station and UAS for flight termination commands. This independent communication path bypasses the primary radio control link, ensuring that kill switch functionality remains operational even when the primary link is lost or interrupted. The intermediary link provides a backup pathway for critical commands.
3Ease of manufacture
If kill switch functionality relies on the primary radio control link, then the system can be simple to implement, but the system becomes vulnerable when the flight controller starts rejecting radio transmitted commands due to software failure
Solution Approach 1:
The dedicated flight termination radio link acts as an intermediary that bypasses the flight controller's software stack. By using a separate communication channel that interfaces directly with the propulsion system or flight controller hardware, the system ensures termination commands can execute even when the flight controller is rejecting commands due to software failures. This intermediary path isolates the critical safety function from software vulnerabilities.
4Reliability
If a dedicated radio link independent of primary operation link is used for flight termination, then the system can operate independently of primary link failures, but the device complexity increases with additional transmitter and receiver components
Solution Approach 1:
The flight termination system components are designed to be integrated into the existing UAS architecture, where the dedicated transmitter and receiver share physical platform and power systems with the primary operation link. This multi-functionality approach allows the same hardware infrastructure to support both primary control and flight termination functions, reducing the net increase in overall system complexity despite adding dedicated termination 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
Effectively prevents uncontrolled flight by ensuring the UAS can be safely terminated, reducing the risk of accidents and enhancing operator control, while the independent radio link and confirmation process enhance security and reliability.
Implementation Method 1
a radio link connecting the FTTx and the FTRx
Data Source
AI summary
Implementations of a flight termination system for unmanned aircraft systems are provided. The flight termination system comprises a ground-based flight termination transmitter (FTTx) located with an operator/observer, an airborne flight termination receiver (FTRx) located on an unmanned aircraft system (UAS), and a radio link connecting the FTTx and the FTRx. The FTTx is configured to communicate a TERMINATE FLIGHT message to the FTRx and, once the TERMINATE FLIGHT message has been confirmed, the FTRx is configured to terminate the flight of the UAS by disabling the propulsion system thereof. In this way, the UAS (e.g., a drone or other unmanned aerial vehicle) may be prevented from flying away in an uncontrolled fashion. The FTTx includes an arming switch that can be actuated by a provided key. The dedicated radio link connecting the FTTx and the FTRx is independent of any radio link used to operate the UAS.