Servo unit for actuating control surfaces or the like of a flight control system.

p0001The invention relates to a servo unit for actuation of belonging to a flight control system control surfaces or the like according to the preamble of claim 1.

p0002Such power units for operating devices such as control surfaces or hydraulic valves, wherein the control commands are transmitted in the form of digital signals are well known and are used inter alia as actuators for numerically controlled machine tools. Here, the traffic of the control commands and feedback led by a program executed as a data bus line system. A common method of address code used in this case is DE-A refer -23 33 968, showing a fiber network for opto-electronic data transmission. The control system in this case has a central control unit, which corresponds via the data bus with the connected units with the aid of the encoded addresses which are associated with these units.

p0003In conjunction with flight control systems based on digital bus waveguides are particularly advantageous because they are insensitive to electromagnetic interference. The DE-A- 26 23 527 shows a method for the simultaneous transmission of messages in a plurality of separate signal channels by means of electromagnetic radiation in the optical range. In this case, the associated channels in the individual signal oscillators generated frequency-modulated carrier waves are combined in a summing circuit and fed to at least one power amplifier stage which modulates the power of the electromagnetic radiation in the optical range-emitting radiation source. By this measure known to transmit messages by means of a frequency-modulated carrier wave by optical fibers, an optical fiber system of a digital flight control in connection with the case conventional amplitude limitation can be protected against lightning Fremdlichteinstreuung.

p0004Standard procedure to make a digital flight control system with a data reliable, persist that the relevant functional units including the respective conductive paths are executed several times and operated in parallel. Furthermore, this digital computers ago known methods of automatic error detection and error correction are applied. Those measures designed to increase the reliability of failure, however, if certain control surfaces or other organs of a flight control system, are out for whatever reason, failed.

p0005Accordingly, the invention is based on the object to form a generic servo unit such that it automatically displays in this case properly reacting, predetermined behavior, for example in case of failure of a particular control surface.

p0006This object is achieved with a servo-unit of the aforementioned type by the characterizing features of claim 1. Advantageous developments are specified in dependent claims 2 to 4. FIG.

p0007In the intelligent storage of emergency programs can be stored to be called in case of failure of certain elements of the control system to the part of certain power units to cause a damage balancing behavior. As actuators of the servo units both hydraulic and electric actuators are suitable.

p0008The invention is illustrated in the drawing and explained in more detail in the description. Show it:<ul><li>Figure 1 is an overview of a digital control system for an aircraft.</li><li>Fig. 2 is a circuit of a main control circuit; </li><li>Figure 3 is an optical device for scanning a position control column.</li><li>Figure 4 shows a block diagram of a motor simulator.</li><li>Figure 5 shows a circuit of a mixer unit.</li><li>Fig. 6 is a block diagram of an optronic information system;</li><li>7 is a block diagram of a servo unit.</li><li>8 is a display and control unit.</li><li>Fig. 9 is a block diagram of a dialogue device;</li></ul>

p0009FIG. 1 shows an overview of the arrangement for the transmission of control signals for a plane F. The plane F includes the usual control surfaces, namely two elevator 1, 1', a rudder 2, two slow flight-aileron 3, 3 ', two Schnellflug- aileron 4, 4', landing flaps 5, 5 ', leading edge flaps 6, 6' and a horizontal stabilizer 7 to aircraft F, inter alia, include the engines 8, 8'and the control members 9, the schematic representation of the control columns 9a and pedals suggests. The conduit system for the transmission of control signals comprises essentially a plurality of signal processors 10 and consisting of longitudinal lines 11 and transverse lines 12 multiply meshed network of optical fibers to which is in communication with addressable servo units fourteenth Nodes 13 consist of branches of known type, eg., In the form of a star or T-couplers. The control means 9 are designed such that they provide a control command to the corresponding digital light signal. Which are arranged at the periphery of the network servo units 14 are equipped with means for converting the incoming light signal in a control movement. They also have facilities that determine the instantaneous position z. B. a rudder and emit a corresponding light signal to the longitudinal lines 11. The running between the signal processors 10 and connected on the longitudinal lines 11 peripheral equipment traffic is performed cyclically, ie the signal processors 10 enter in solid inquiry cycle addressed information signals z. B. from the servo units 14, answer in turn with the addressed information signals. The herein concurrent data traffic is defined in the form of telegrams with fixed length. These telegrams are a carrier frequency in the form of a digital frequency modulation is impressed, the light signal ultimately having a carrier frequency corresponding amplitude modulation. This results in a very high noise immunity is obtained against any Fremdlichteinstreuung. Due to the meshing is ensured that the signal in many ways from the signal processors 10 come to the mentioned servo unit 14, whereby the reliability of the system is further increased. The illustrated system is performed in triplicate, that is disposed in the hull 11, works in the wing and in the Leit are three longitudinal lines with corresponding transverse conduits 12 and per rudder control surface, or the like. Three servo units 14 are provided. The signal processors 10 include the main control circuit of the entire arrangement. Also this unit is designed to increase the reliability in triplicate.

p0010Fig. 2 shows the circuit of one of the signal processors 10, which consists essentially of a mixer 15 and three information systems 16, 17 and 18. About triplicate light pipes 19 of the mixer 15 with a meshed donor network 20 of optical fibers connected. The triple output of the mixer 15 is connected to each one of the information units 16 to 18. Each unit 16 to 18 further includes three terminal light lines 16a to 18a, 12 is respectively connected to the network 24 from the longitudinal lines 11 and transverse lines connected. The mixer 15 accepts the task here the z. B. from the steering column coming digital light signals prepare so that they are forwarded under logical consideration of additional information to the information systems 16 to 18. If the mixer 15 z. B. a signal corresponding to a predetermined target altitude and another of an altimeter 22 supplied signal corresponding to the actual amount supplied, the mixer 15 forms one serving to adjust the desired altitude difference signal, which is input through the information systems 16 to 18 in the network 24th This addressed to the servo unit 14:01 of the elevator frame is now received by this unit and converted into a corresponding deflection of the rudder 1, which returns the aircraft without help from the pilot back to the target altitude. In the same manner provided by a navigation device 23 price-actual values ​​can be compared by the mixer 15 with a predetermined desired course. The hereby resulting difference signal is converted in an addressed to the servo-unit 14.2 of the rudder 2 and to the servo-units 14.3 and 14.4 of the ailerons 3 control command and on the information systems 16, 17 and 18 and further via the network 24 said servo units, respectively. This answer with a rudder which causes the required course change. A not shown on the transmitter network 20 connected to the mixer 15 display and control unit is used, inter alia, the graphical representation of the set and actual values ​​using conventional symbols. the target actual comparison If the arrangement is switched to manual operation, so deleted by the mixer and the incoming via the transmitter network 20 control commands are sent directly in the form of corresponding telegrams to the servo units concerned. At the transmitter network 20 all are a control command issuing control means 9, such as control columns, pedals, exercise bike, etc. connected via a triplicate light guide. In the above processes, the object of the information systems 16 to 18 essentially is to control the traffic of one in the mixer unit 15 and outgoing data through a certain cycle and to provide the command or query telegrams with the corresponding addresses.

p0011Fig. 3 shows the schematic diagram of an optoelectronic device 25 for position sensing of the steering column 9, works as a signal generator. It consists essentially of a solid arcuate portion 25 a having on the inside thereof arranged light receiver diodes 26, which are respectively connected to the input of a coding matrix 27th The fixed part 25 a is on the inside of a rotatable about a point 28 segment-shaped part 29 with respect to such that the point 28 coincides with the center of the inner contour of the part 25 a and a portion of the rotatable member 29 to the fixed part 25a has an arcuate gap with the center 28 forms. In the arcuate edge surface of the rotatable part 29 light transmitter diodes 30 are arranged such that the light emitted by this light is received directly from the diodes 26th The light transmitter diodes 30 are connected to a switching matrix 31 in connection, which is supplied from the electrical system with electricity, but three backup batteries 32, 33 and 34 are provided. The switch matrix 31 provides a predetermined electric pulse pattern, whereby the diodes emit 30 specific digital light pulses. The movable member 29 is so connected to the control column 9a that it follows the movements of which in Solid dependence. In this case, assume the receiver diodes 26, a light signal which corresponds to the respective position of the control column. This signal 27 is converted by the coding in a digital light signal which is continuously interrogated through the mixer 15th If the on-board network dependent power diode fails, the corresponding energy is supplied by the backup batteries 32 to 34. The auto switch operates the more accurate are the more diodes per sheet unit housed. An increase in the accuracy is further characterized reached in that the movable member is driven via a reduction gear 29 of known type. By a logic circuit can be achieved, that the reading by the encoding matrix and then is still clearly if one of the three light emitter diodes 30 should fail during operation. According to the invention, the other control members such as pedals, exercise bike, etc. may be equipped with optronic devices 25 of the type described. The interchange of light emitter and receiver diodes results in a further variant of the optronic means 25th

p0012Fig. 4 shows a block diagram of a motor simulator 35. Such devices to simulate the rudder forces are known per se and are usually based on rather complicated mechanical transmissions. The solution shown here works electromagnetically and is controlled via a light guide.

p0013The force simulator 35 consists essentially of a control unit 36, an electronic simulator unit 37 and an electric motor 38. The above-described mixer 15 supplies via optical link to the force simulator 35 addressed signals corresponding airspeed. These signals are selectively received by the control unit 36 ​​and forwarded as electrical digital signals to the electronic simulator unit 37th due to aircraft related fixed feature equation as a function of airspeed and the respective rudder This emits a certain electric power to the motor 38th This provides for a standstill via a shaft 38 a a corresponding torque M_d' the right z. B. on the control column 9a such acts that here a palpable for the pilot force occurs, which corresponds to the rudder forces in a meaningful way. Due to the 37 stored in the simulator unit program, the direction of the torque is reversed, when the control column 9a passes through the neutral position. The airspeed corresponding input to the mixer 15 signals z. B. derived from the measurement result of a pitot tube, not shown, via an analog-digital converter and fed via an associated addressable control unit in the form of a digital optical signal in the encoder network 20.

p0014Fig. 5 shows the internal circuit of a mixer 15 with two in each case one control column 9a associated connection units 39 and 40 with three central processor - units 41, 42, 43, each of which is a memory 44 associated with 45 and 46. The mixer 15 further comprises for each institution which can give a command, a corresponding, not shown here, connecting unit on. The mixer 15 further includes memory per each one vertical reference 47, 48, 49 and on a horizontal reference 50, 51, 52nd For connection to the control columns 9a and force simulators 35 are optical fibers. The individual in internal functional units of the mixer 15 to FIG. 5 are respectively connected together by electrical lines. The compounds with the information systems 16 to 18 are also made via electrical lines. The z. B. of the pedestal 9a coming coded signals are fed into the bonding unit 39, which in turn consists essentially of amplifiers and code converters. Here the said signals are amplified and transcoded and passed to the mixer internal data bus, which communicates with the central processor units 41, 42 and 43rd A priority circuit within the connection units ensures that the signals of the steering column 9a' so long priority until by operating the control column is 9a" turned on and then taking the lead. In the memories 44, 45 and 46, the 47 to 49 and 50 supplied by the references to 52, the actual position of the aircraft are stored corresponding data and compared with each other on the processor units 41 to 43rd In this case, those data are recognized as correct, which are present in the plurality of processor units 41 to 43 coincident. The processor unit with differing information is found to be faulty and disabled via the internal data bus mixer. This is done using a special error code signal. The processor units 41 to 43 are also the ones which perform the necessary operations for the aforementioned automatic flight guidance. A suitable processor is z. B. under the designation PDP 11/70 known. According to FIG. 1 has the whole arrangement of three signal processors 10, and thus also over three mixers 15, causing a corresponding increase in reliability.

p0015Fig. 6 shows a block diagram of an optronic information systems, as is provided in triplicate to Fig. 2 within the signal processor 10 with positions 16, 17 and 18. The illustrated system comprises three processors 53, 54, 55 with three memories 56, 57, 58, three coders / modulators 59, 60, 61, three demodulator / decoders 62, 63, 64, three transmitters 65, 66, 67 and three receivers 68, 69, 70 which are interconnected. An essential component of the stations 65 to 67 is a laser diode which can emit a light signal to the network 24 respectively. The receiver consist essentially of one silicon phototransistor which serves as a detector for incoming over the network 24 light signal, that is, converts it again into electrical signals. The information system is shown to increase the reliability of three branches, which operate in parallel. To explain the mode of action is at first only the branch shown on the left, consisting of the processor 53 to the memory 56 and the coder / modulator 59, the demodulator / decoder 62, the transmitter 65 and the receiver 68 will be considered. This circuit controls the running between the network 24 and the mixer 15 traffic, whereby an integrated into the processor 53 oscillator acts as a clock. From the mixer 15 to the processor 53 succeeded electrical signal is supplied to the coder / modulator 59th Within the coder part, the data message is converted by the processor related to the peripheral related word and address structure. Then the frame passes through the modulator part, where it is imparted a high-frequency carrier in the form of frequency modulation. The corresponding pure data content is then recovered by demodulation in an intermediate step and a solid carrier other imprinted by amplitude modulation. The signal thus produced is amplified within the transmitter 65 and supplied to the laser diode, which emits a light to the diode current analog signal to the network 24th In the reverse direction through the network 24, an incoming light signal from the receiver 68 is absorbed and converted back by the built-in phototransistor an amplitude-modulated electric signal, which is then passed to the demodulator / decoder 62nd

p0016At the output of the demodulator / decoder 62 then again lies before a data telegram in processor-based structure, which will be further processed by the processor 53rd The other two branches of the system result in the same cycle of the same operations, the synchronizing pulse of clock of the processor 53 starts. If this clock fails, the branch shown on the left is automatically switched off and the next planned clock controls the synchronization. Even further provided according to FIG. 2 information systems 17 and 18 are synchronized normally by the processor 53. The corresponding Sychronisier pulse is passed through the network 24th

p0017Fig. 7 shows the block diagram of a servo unit 14, for. Example, for operating the elevator 1, which has a mechanical and an electronic part. The mechanical part here consists essentially of a setting cylinder 71, a push rod 72, and two servo valves 73. The electronic part comprises two servo amplifiers 79 and 80, a processor unit 81, a modulator 82, a demodulator 83, a transmitter 84, a receiver 85, a position transducer 86, a memory 87 and a power supply section 88 which are interconnected. The aforementioned functional units consist mainly of integrated circuits and are advantageous in an electronics chamber of the housing from the actuator cylinder 71st Thereby forming the actual actuator cylinder 71 with the electronic part of the novel continuous servo unit 14, which in addition to the hydraulic pressure (74, 75) and return (76, 77) leads a terminal 89 for power supply and two optical fiber ports 90 and 91 has. An incoming via the light guide 11 addressed by the information systems 16, 17, 18 to the adjusting cylinder 71 the light signal is converted by the receiver 85 into an electric signal, and the demodulator 83 supplied to the original data telegram is derived from this signal, and inputs to the processing unit 81 which has a built-in decoder, which converts the message to their own polling cycle and switched to an internal data bus. In memory 87 different possible operating programs of the actuating cylinder 71 are stored. Because of the telegram a particular program from the memory 87 is now called to control the servo amplifiers 79 and 80 in turn cause an electrical drive of the servo valves 73rd These control the supply and return flow of pressure fluid such that the push rod 72 the elevator 1 is not shown here, given the sequence of movements, corresponding to the retrieved program. The memory 87 may be implemented as semiconductor or magnetic bubble memory. The addressable programs are stored in the form of mathematical functions that allow both fast or slow and linear or nonlinear control surface. By means of the stored features different control requirements can be met. So for example it is possible to adjust the control surface of the respective airspeed. Furthermore, it is possible to store certain emergency programs, whereby the failure of important rowing can be compensated. It is, for. Example, conceivable, the failure of an aileron 3 offset by the fact that you are antisymmetric elevator deflections or the failure of the rudder 2 to compensate the fact that the lying on the inside of the intended curve ailerons 3 and 4 and 3 'and 4' in the opposite direction be knocked out. Another novel due to the invention possibility is that z. B. a force acting on the wing unilateral gust is compensated by a rapid unilateral aileron. To this end, the aileron is used in each case, which is the last attack the next. Such reactions can be, for. Example, by signals from accelerometers arranged in the wings of conventional type can be initiated. The above examples indicate just which beneficial effects with the arrangement with appropriate programming are possible. The position sensor 78 provides a the respective position of the push rod 72 corresponding signal to the position transducer 86, which consists of an analog-to-digital converters substantially. The signals supplied by this are supplied to the processor unit 81, where they are used to control the on-propelled program. Furthermore arrive corresponding telegrams per query running through the modulator 82, the transmitter 84 and the light guide 11, 12 to the information systems 16, 17, 18, which thus can control the operability of the servo unit 14th

p0018The memory 87 contains according to the above different from the setting cylinder 71 (or z. B. by an electric servo-motor) to be executed actuation programs and also serves to monitor them based on the signals supplied by the position sensor 78th Such memories are also called "smart memory". The processor unit 81 z. B. the known block INTEL 8080 is concerned.

p0019Fig. 8 shows a block diagram of a display and control device 92. The device includes a processor unit 93, an electronic image unit 94, a screen 95, a keyboard 95a, a coder 96, a transmitter 97, a decoder 98 and a receiver 99 which are interconnected. The transmitter 97 and the receiver 99 are via optical fiber to the transmitter network 20 in connection. The alphanumeric keyboard 95a, the z. B. by ASCI code (ascii) operates the input of operating data in the transmitter network 20 for carried fixed modes are particular provided with appropriate symbols dial keys. Here z. B. can be selected the basic modes such as manual (Manop), semiautomatic (semop) or auto matic (AUTOP) control. The processor unit 93 has, inter alia, the task of preparing the supplied from the keyboard 95a signals such that they polled in the form of data telegrams via the coder 96 and the channel 97 transfer via optical fiber to the mixer 15th The screen 95 is on the electronic screen unit 94 to the processor unit 93 in connection. The image unit 94 essentially comprises a signal generator and a code conversion matrix, as are commonly used for image display. Such a circuit is made of small "micro-computer systems", Francis Verlag, Munich, 1979, 2nd ed p.32 known.. The screen 95 is designed as a semiconductor screen and is used both for the actual situation of the aircraft F and for displaying of performed tax adjustments. The signal generator of the image unit 94 serves in this case for processing the figurative representation of attitude and heading information (bar, course numbers), for the manufacture of alphanumeric characters to ASCII code and for the preparation of the symbols for the control commands. The code matrix converter controls the dot matrix fields of the screen 95, so that the instant in the code of the signal generator digital signals are converted into the corresponding representations. The entire assembly has three of the above display and control units 92, which correspond via the transmitter network 20 to the mixers 15th Thereby both the pilot and the flight engineer come with an own display and control unit 92, the scenes shown in each case and executed operation measures usually due to the different tasks of operators are completely different. Here are the possibilities that arise by programming the circuit shown, only hinted at.

p0020Fig. 9 shows a block diagram of a dialog device 100, with the results in a meaningful construction of the arrangement. The dialogue unit 100 essentially consists of a voice analysis unit 101 which communicates with a microphone in connection, and a voice synthesis unit 102, which is connected to a loudspeaker. The dialogue unit 100 corresponds to the processor unit 93 of the display and control unit 92 of FIG. 8, allowing a linguistic dialogue the operator with the described arrangement. Here, by voice input via the microphone code words are recognized by the voice analysis unit based on a stored here syllable treasure and entered in the form of corresponding digital telegrams in the processor unit 93rd This is done using a so-called. PROM speech decoder (PROM = programed read only memory). Conversely, can now be issued a key to the operator information about the speaker. Here the speaker via a not shown power amplifier, the voice synthesis is carried out within the unit 102 by a PROM voice coder, and allocated the 93 supplied by the processor unit telegrams and compiles the corresponding dispensed words because of a stored here syllable treasure and these audio-frequency signals supplies.

p0021The messages exchanged in the above described system via the meshed optical fiber networks 20 and 24 light signals are not limited to the modulation type described, but depending on the application, other types of modulation, such as pulse frequency modulation (PFM) or pulse code modulation (PCM), possible ,