GB2158610A

GB2158610A - Aircraft control

Info

Publication number: GB2158610A
Application number: GB08409338A
Authority: GB
Inventors: Stanley Beddoe
Original assignee: Plessey Co Ltd
Current assignee: Plessey Co Ltd
Priority date: 1984-04-11
Filing date: 1984-04-11
Publication date: 1985-11-13

Abstract

A control system comprising a master control computer capable of sending programmed instructions to and of receiving status information from a plurality of remote intelligent terminal units connected to the master control computer over common data highway means, the remote intelligent terminal units being located at predetermined strategic operational points of the controlled aircraft, vehicle or other means for controlling various utility functions and at least one of said units comprising a microprocessor which provides local intelligence and authority to perform predetermined defined functions in accordance with command instructions received over the common data highway means and programmed to take immediate action in respect to said functions in the absence of command signals over the data bus or failure of equipment under its control. <IMAGE>

Description

SPECIFICATION Improvements relating to microprocessor control systems This invention relates to microprocessor control systems eminently suitable for aircraft.

Many aircraft control systems have been designed to reduce the pilot's workload and to control those aircraft functions which need to be monitored and, if necessary, corrected or adjusted faster than human response will permit.

Central microprocessor control systems for such functions as aircraft engine control, flight surface control and flight guidance control have already been highly developed whereas the development of control systems for the so called utilities systems of aircraft has been very slow. These utilities systems of aircraft include electrical secondary power, hydraulics and fuel control or management.

According to the present invention therefore there is provided a control system eminently suitable for aircraft which comprises a master control computer capable of sending programmed instructions to and of receiving status information from a plurality of remote intelligent terminal units connected to the master control computer over common data highway means, said remote intelligent terminal units being located at predetermined strategic operational points of the aircraft for controlling various utility functions (e.g. fuel control or hydraulics) and said units each comprising a microprocessor which provides local intelligence and authority to perform predetermined defined functions in accordance with command instructions received over the common data highway means and programmed to take initial action in respect to said functions in the absence of command signals over the data bus or in the event of local faults or failure of equipment under its control.

A remote intelligent terminal unit may comprise the following components: (a) An interface unit to the data highway which will be electrical or optical. This unit will receive the commands from the master control computer addressed to the terminal unit and will send status information etc. back from the terminal unit to the master control computer; (b) A microprocessor and associated memory with the necessary inputs and outputs for managing all actions of the terminal unit and for carrying out any level transformations or calculations; (c) A power controller (i.e. a solid state remote power controller); and, (d)lnput controls which receive status signals from sensors fitted to the equipment being controlled by the unit. These inputs may be electrical or optical and will include inputs from such dedicated sensors as ice detectors.

By way of example, one embodiment of the present invention will now be described with refer ence to the accompanying drawing in which: Figure 1 is a block schemaatic diagram of an aircraft control system; and Figure2 is a block schematic diagram of an exemplary intelligent sub-system of the overall control system depicted in Figure 1.

Referring to Figure 1 of the drawings, the aircraft control system illustrated in block schematic form comprises a master controller computer 1 which may be programmed in accordance with various functions to be performed by different parts of the aircraft's equipment. For example, the master control computer may be operatively coupled to the usual avionics display panel of the aircraft indicated at 2 so that control instructions may be transmitted to the panel whilst avionics status signals may be transmitted back to the computer 1 for appropriate evaluation in relation to the stored avionics information. Similarly, directions relating to the aircraft pilot's contol may be transmitted by the computer to pilot's control equipment 3 with control status feedback being provided to the computer from the equipment 3.Modern aircraft have a mutliplicity of control and/or operating gear and sensors distributed throughout the aircraft. For example, a fuel control system is provided to contol the flow of fuel to the aircraft engines, hydraulic control systems are provided inter alia for the operation of landing gear, wing flaps etc., and temperature sensors are provided to monitor engine and wind shield temperatures. Many of these equipments distributed at remote points throughout the aircraft also require electrical power for their operation.

The present invention accordingly provides a plurality of so-called intelligent sub-systems such as the sub-systems shown at 4, 5 and 6 which are linked with the master control computer 1 over a data highway 7 which may be electrical or optical, utilising optical fibre technology. Each of these sub-systems 4, 5 and 6 which will be advantageously deployed at convenient locations throughout the aircraft according to the positions of the equipment under their control is arranged to receive over the data highway 7 command instructions from the master control computer 1 appropriate to the equipment under the control of the particular subsystems. Sub-systems will usually include their own individual solid state power controllers for energising the equipment being controlled and for generating control signals for transmission to the equipment concerned.

These intelligent sub-systems however which receive instructions from the master controller computer 1 are each rendered intelligent by the provision of an individual microprocessor which will be pogrammed for exercising control over the equipment appertaining to it under conditions where command instructions fail to be received from the master control computer by the microprocessor or when equipment associated with the sub-system becomes faulty, or fails completely, requiring immediate initiation of defined fault procedures, perhaps involving the introduction of secondary or replacement equipment. Such initial action required to correct the situation will be initiated by the microprocessor of the intelligent sub-system concerned which will be appropriately programmed for dealing with such eventualities by initiating certain defined actions.At the same time, warning signals will be fed back from the terminal in question over the data highway 7 to the master control computer 1 which will advise the pilot of the fault concerned and of the immediate action taken, thereby giving him a choice of further actions should he consider these to be necessary. The kind of actions envisaged include fire control procedures, engine failure, aircraft damage, such as due to mid-air collision etc., and electrical system failure.

As will be apparent from the drawing, each of the intelligent sub-system controllers will have groups of output control leads 8, 9, 10 extending to the various equipments under their control such as fuel control system or hydraulic gear and they will also include groups of input control leads 11, 12 and 13 over which status signals, as from sensors, are fed back to the intelligent sub-system for appraisal and appropriate action on the part of the microprocessor.

As will be appreciated from the foregoing description of one embodiment of the invention, the control system described not only provides great flexibility of action by providing a plurality of intelligent sub-systems each with its own programmed microprocessor and power contoller, but the present day technology in solid-state devices enables such a control system to be provided, which is sufficiently cheap and small in size to be easily accommodated within the aircraft.

Although the present invention is particularly applicable to aircraft it should be understood that it does have other applications having similar complex and critical operating requirements (e.g. vehicle control, oil rigs, power and processing systems).

Claims

1. A control system comprising a master control computer capable of sending programmed instructions to and of receiving status information from a plurality of remote intelligent terminal units connected to the master control computer over common data highway means, the remote intelligent terminal units being located at predetermined strategic operational points of the controlled aircraft, vehicle or other means for controlling various utility functions and at least one of said units comprising a microp rocessorwhich provides local intelligence and authority to perform predetermined defined functions in accordance with command instructions received over the common data highway means and programmed to take immediate action in respect to said functions in the absence of command signals over the data bus or failure of equipment under its control.

2. A control system as claimed in claim 1, in which one or more of the terminal units comprise an interface unit to the data highway which is electrical or optical and in which the unit(s) receives commands from the master control computer addressed to the unit(s) and sends status information back to the master control computer.

3. A control system as claimed in claim 1 or2, in which the microprocessor has an associated memory with the necessary inputs and outputs for managing all returns of the terminal units and for carrying out any level transformations or calclations.

4. A control system as claimed in any of claims 1 to 3, in which one or more intelligent units comprise a power controller.

5. A control system as claimed in any preceding clam, in which one or more of the intelligent units include input controls arranged to receive status signals from sensors fitted to the equipment being controlled by the unit.

6. An aircraft control system according to any preceding claim.

7. An aircraft control system substantially as hereinbefore described with reference to the accompanying drawings.