Synchronized Thrust Reverser Locking via Dual Control Units
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing thrust reversers for bypass turbojets lack synchronization in the control of primary locks, leading to potential failures and safety issues when one lock jams or fails, as they are controlled in parallel without genuine synchronization.
Innovation Solution
A turbojet thrust reverser with two displaceable doors, each controlled by a respective electronic control unit connected to a FADEC, featuring synchronized locking devices that require simultaneous orders from both units to actuate, ensuring that if one unit fails, the locking devices remain locked or brake the doors, enhancing safety.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If primary locks are controlled in parallel during reverser opening and closing sequences, then the control system is simple and responsive, but synchronization cannot be ensured and safety is compromised in the event of one lock failing or jamming
Solution Approach 1:
A synchronizing unit is introduced as an intermediary component between the two electronic control units and the primary locks. This synchronizing unit receives control signals from both electronic control units and coordinates the actuation of both primary locks, ensuring that they can only be controlled when both doors are properly positioned. This mediator resolves the contradiction by adding coordination logic that enhances safety without requiring complex direct interlocking mechanisms between the locks themselves.
Solution Approach 2:
The system implements feedback through position detection means that continuously monitor the position of each door and provide this information to the electronic control units. The control units use this feedback to determine when the doors are in the correct position before allowing control of the primary locks. This feedback mechanism ensures synchronized control and prevents unsafe operation while maintaining system responsiveness.
2Reliability
If one electronic control unit breaks down, then system redundancy is lost, but with synchronized control the locking devices remain locked or automatically brake the doors
Solution Approach 1:
The system prepares for potential failures in advance by implementing a safety mechanism where the primary locks are designed to remain locked or automatically brake the doors if one electronic control unit breaks down. The synchronizing unit detects control unit failures and triggers a safe state, cushioning against the harmful effects of control unit breakdown before they can compromise safety.
Solution Approach 2:
The system takes preliminary anti-action by preventing the primary locks from being controlled if the synchronizing unit detects that one electronic control unit has broken down. This preliminary prevention stops potential unsafe actions before they can occur, ensuring that a single point of failure does not lead to system compromise.
Data Source
AI summary
A turbojet thrust reverser has two doors that are displaceable between a reverser open position and a reverser closed position, each door being controlled by a respective electronic control unit connected to a FADEC, and each door having a respective locking device for locking the position of the door associated therewith. Each locking device can be unlocked solely on receiving orders that come simultaneously from both electronic control units.