This document summarizes a parallel processing control system for aircraft durability testing. The system uses distributed processing across a network of controllers linked by fast communication. Each controller is located near actuators to provide high-speed synchronous multi-input multi-output control up to 1000Hz across up to 511 controllers. Parallel processing is used for system management, control, data acquisition, and communication. The distributed architecture provides flexibility, maximizes testing speed, and has proven suitable for aircraft testing.

1. Application
Parallel Processing in
Distributed Real Time Control of
Aircraft Testing
Prepared by :
Rohayu Mohamed
Siti Nor Fatin Ghazmi
Siti Fatnin Mohd Na’izam

2. Introduction
• An innovative multi-channel digital control
system for durability testing of aircraft has
been developed at the Defence Science and
Technology Organisation, Australia.
• It is currently in use on a full-.wale durability
test of the FIA-18 aircraft for the Royal
Australian Air Force.
• The system using parallel processing and inter-
processor communication.

3. • This system is based on a network of controller processors
physically distributed over the test rig
• One processor at each actuator station with a single system
management processor
• All linked by fast inter-processor communications for system state
and control state-variable data.
• Parallel processing is used to implement system management.
Multiple Input Multiple Output (MIMO) control, data acquisition
and communications.
• Full-scale aircraft durability tests are one-off tests whose control
requirements typically change as the test rig is developed. Once
commissioned, tests often run for several years.
• The system described here was motivated by a need to reduce the
set-up and running time of tests by providing flexibility during test
rig development and maximising testing speed

4. Parallel architecture used
• This system is based on a network of
controller processors physically distributed
over the test rig, with one processor at each
actuator station. and a single system
management processor; all linked by fast
inter-processor communications for system
state and control state-variable data

5. • It provide high-speed synchronous MIMO control at
update rates to 1OOOHz. Up to 511 separate
controllers. each using one Inmos T805 Transputer as a
processor, are connected in a binary tree to make a
single distributed control system.
• A special hardware broadcast link spans the whole
network tree and provides critical real-time
communications and synchronisation.
• Controllers are located adjacent to actuators. with up
to 20 metres between any pair of directly connected
controllers. Pneumatic, hydraulic and electromagnetic
actuators are supported, with appropriate control laws.

8. The advantages of using the proposed
architecture
• To provide high-speed synchronous MIMO control
at update rates to 1OOOHz.
• To control systems for aircraft testing consists of a
centralised m y of independent PID style
controllers with command inputs provided by a
central computer.
• Parallel processing is used to implement system
management. Multiple Input Multiple Output
(MIMO) control, data acquisition and
communications

9. Conclusion
• The exercise of desiping, implementing, and applying this
system to a number of small tests and one large test has
confirmed the suitability of the distributed parallel
processing model described above. Performance targets
have been met and, as intended. the system has proved to
be easy to install and reconfigure. Enhancements envisaged
for the current system include more built-in support for
system identification and improvements in the way new
control law software is generated. with direct links to a
control system modelling and analysis software package
such as Matlab or MATRIX,. While design goals have been
met with the cumnt hardware, implementation of the
software would have ben easier with a faster processor and
faster communications.