Machine control process supervision system device with CAN-protocol e.g. weaving looms in weaving shed

(54) NAME Device for control and / or monitoring system (56) PUBLICATIONS QUOTED:

SEE B 468 532, EP A 610 999 (57) SUMMARY:

A CAN system includes a digital serial communication (5) and modules connected to it (1-4). A function in a first module or to this controlled equipment unit is intended to be viewable or recordable at a location (A) for the first module and the unit location, respectively. A radio communication equipment is provided for connection with a part (9) to a second module (4) in the system. A radio communication channel is established between said location (A) and a location (B) for the location of the second module. The radio communication equipment is activatable at the first location for initiation via a radio channel and said part (9) of a signal activation (i2) in the second module. This signal activation causes the first module to fail in the system in the exercise of its control and / or monitoring function, which thus becomes viewable or recordable at the first mentioned location (A).

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The numbers in brackets indicate international identification code, INID code. Letters in clamps indicate international document code.

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TECHNICAL FIELD

The present invention relates to a device for machine control systems or process control systems. The said system has in this case been referred to as CAN system because the systems in question were assumed to utilize the signal protocol according to CAN (Controller Area Network, corresponding to standard ISO 11898). The invention thus relates to such CAN systems comprising modules which can be connected via a digital serial communication where a function in a first module is intended to be viewable, affected or recordable at a location for the location of the first module. Reference is also made to the Swedish patent application Device for systems that work with CAN protocols filed the same day by the same applicant and inventor.

BACKGROUND OF THE ART

It is known in the relevant types of machine control and process control system that it is necessary to monitor the sub-equipment served by the modules so that, for example, troubleshooting, system design, etc. can ascertain whether the equipment (s) controlled by each module behaves as expected. It may be mentioned here that one may need to check the functions of valves, thermostats, thermometers, etc. say that in certain operating modes you can see or record whether the components in question are actually performing their expected function. It is also known to utilize machine control systems and process control systems where the equipment parts are connected via relatively long digital serial communications. The connection can also be carried out in places and places where accessibility is limited.

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DISCLOSURE OF THE INVENTION

TECHNICAL PROBLEM

There is a great need to be able to troubleshoot and test modules that are spaced apart and where a function's impact on a first module is desired to be followed by a second module, and vice versa. So e.g. In some situations, it is desirable to initiate controls of a master in the CAN system in order to get the opinions of one or more slave modules. There is, therefore, a need to see if the function is performed correctly by the components or sub-equipment controlled by the current module.

There is also a need to be able to influence a component or sub-equipment in a module and to gain knowledge of what the impact entails.

There is also a need to be able to perform registration procedures in troubleshooting and test contexts for a certain period of time, as well as obtaining immediate visual and signal information at the location of the module being tested or debugged.

The above must be possible even if the modules are located at a great distance from each other and hidden from each other. Preferably, the above can be done via an already existing switching function, ie. Connections and disconnections do not have to be made for each separate case / module.

The invention is intended to solve all or part of the above problems.

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-4LÖSNINGEN

What can essentially be considered a characteristic of a device according to the invention comprising the module mentioned above is that a radio communication equipment is provided for connection with a part to a second module in the system for establishing a radio communication channel between the location of the first module location and a location. for the location of the second module. At the location of the location of the first module, the radio communication equipment is activatable for initiation via a radio channel and said part of the radio communication equipment of a signal activation in the second module. This signal activation causes the first module to perform its respective control and / or monitoring function which thereby becomes viewable or recordable at the location of the first module.

In one embodiment, the CAN system is included in a machine control system and / or a process control system where a first signal exchange according to the CAN protocol exists between the modules involved in the system for the control and the exercise of the process. A first activation of the radio communication equipment at the first location thereby causes a second activation of circuits in the second module. This second activation causes said signal activation in the second module.

In a further embodiment, the signal activation caused by the second activation causes message initiation in the second module, which prepares

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-5 message transmission via the module communication circuit, over the connection to the first module. In this way, the second module can send the message thus generated with a predetermined priority order in the ordinary message or signal exchange between the modules. In one embodiment, the second module may cause interruptions in the ordinary message or signal exchange in the CAN system. The signal activation initiated by the second activation in the second module takes over the CAN system for generation and transmission via the communication circuit and the connection to the first module of one or more sample messages.

The second module can, in its signal activation due to the second activation in the second module, mimic a control or monitoring function that can normally occur in the machine and / or process control system. Alternatively or in addition, a control and / or monitoring function that is distinctive to the test function can be generated.

The radio communication equipment preferably operates bidirectional (half or full duplex). In this way, it is possible that an influence of the control or monitoring component (s) or equipment (s) at the first module provides feedback to the second module, via the connection to the second module. The latter generates an impact responsive information signal, which is returned to the radio equipment portion located at the first module. Information transmitted via the radio communication equipment can thus be indicated

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-6or presented on or at said radio communication equipment portion of the first module.

In one embodiment, the radio communication equipment portion of the first module is connected to the control and / or monitoring equipment served by the first module and / or directly to the module.

In one embodiment, the second module is arranged to be only a so-called. gateway between the first unit's radio communication and the CAN system, ie. a message from the first module via radio to the second module is converted into a CAN message and transmitted on the bus and vice versa.

Further features are apparent from the following claims and description. The device thus also works in the case where the equipment in the first module is affected e.g. manually, which effect can be checked on the control or information delivery unit to determine if there is a fault in the equipment and / or communications.

BENEFITS

Through the above it becomes possible to easily test and function test on CAN modules by means of simulated controls and impacts that are introduced on other modules at a distance from the first modules. The checks can be performed even if connection515,347

-7line is long, e.g. 800 m, or if the modules are hidden from each other. Impacts can also be performed on the monitored module or its equipment / components and the reactions to such impacts can be obtained elsewhere in the CAN system and noted at the site of the first module or modules.

DESCRIPTION

A presently proposed embodiment of a device having the characteristics significant to the invention will be described in the following with reference to the accompanying drawings, in which Figure 1 is a principle and block diagram diagram of a CAN system where radio communication equipment parts are arranged at first and second modules of the system. and where the radio communication equipment is connected to the second module in order to simulate influences therein, whose effect on the system can be controlled at the first module, Figure 1a shows in principle the long transmission distance antenna system for equipment according to Figure 1, Figure 2 shows in block diagram form the structure of the module 4 according to Figure 1, and Figure 3 shows in diagram form the frame structure for digital signals used.

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DETAILED EMBODIMENT

In Figure 1, a machine control and / or process control system is represented with its modules 1, 2, 3 and 4 which are mutually communicable in a manner known per se via a serial digital connection 5. In order to simplify the production, the term CAN system is used on this system. According to the invention, the module in said machine control system and / or process control system serves component equipment. In Fig. 1, a valve in the sub-equipment is indicated by 6 and a thermometer in the sub-equipment is indicated by 7. The length L of the connection 5 can be relatively long and extend e.g. 200 m. The modules and sub-equipments in the systems can also be located out of sight of each other.

In the case of related systems, there is a need to be able to initiate troubleshooting, testing, control, etc. in the first module 1. Such a troubleshooting or equivalent may require that other modules in the system need to be affected or establish signal transmissions or signal receipts at certain stages of the troubleshooting or equivalent. For personnel saving purposes, a radio communication equipment consisting of two radio communication equipment parts 8 and 9 is used. The first portion 8 may be detached from the CAN system, while the communication portion 9 is connected to or included in the second module. The connection between the part 9 and the module 4 can then be made via a connection 10 which can be a physical connection, a non-galvanic connection, a wireless connection, etc. The module 4 can be temporarily or permanently connected to the CAN bus. The radio communication equipment 8, 9 in the present case operates with bidirectional connections 11, 12. The communication equipment 8, 9 can thereby utilize one or more channels and preferably radio channels are used in the broadband area, ie in the frequency range above 1 GHz, for example the ISM band. The radio communication equipment part 8 is provided with a control panel 13 which may be of a kind known per se. The panel is connected to the transmitting and receiving unit 14 of the part 8, which can otherwise be of the same type as 9, via an adaptation unit 15. In addition, the panel may be connected directly to the components served by module 1. This adapter is symbolized by

17.

the sub-equipment or connection is made via and the connection that the first one served a second one is

An initiation 11 of the panel 13 causes an activation of the transmit part 14 which transmits via a channel 11 over the activation to the radio receiver part 9. This reception causes a signal generation i2 to the module 4 via an adaptation unit 23. The module comprises a microprocessor 18 which causes the generation of a signal message. 19, which is transmitted via the communication circuit 20 of the module 4 to the connection 5 (see Figure 1). The broadcast can take place in a priority order determined by the CAN protocol, where the module after access to connection 5 can send the message in question to the first module. Upon receipt of the message 19 in the first module, a functional effect caused by the initiation 1 on the control panel is effected on the component 6, 7 or on the equipment in question. The control can then consist of a switching of the valve 6, an increase or decrease

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-10 of temperature 7, etc. Said switching or temperature change may be visible to a viewer at the first module. The viewer can thus, through the influence of his control unit 13, get visible evidence of whether the control in question is executing what it is intended to do. At controller 13, information i3 can also be obtained from the components or sub-equipment served by module 1. By keeping the radio communication equipment connected, registration and consideration can be done for shorter or longer periods of time.

Alternatively, a manual, electrical or other influence on the components or sub-equipment served by the first module 1 can initiate a message 21 generated in the first module which is transmitted to the second module 4 via the communication circuit 22 in the first module and the connection 5. Said signal message 21 causes a signal initiation i4 in the second module and activation of the transmitter portion in the radio communication equipment portion 9. Via a channel 12, the information in question is transmitted to the receiving part of the radio communication part 14, thereby causing an information signal i5 to be generated to the adaptation unit 15 for forwarding to the control unit 13 or an information giving unit, at which the information is presented or recorded. A location or location for the first module 1 is indicated respectively by A, while the corresponding place or location of module 4 is indicated or indicated by B. After the operator has performed control or troubleshooting at module 1, he can go to, for example, module 3 and perform the corresponding work, provided that module 4 is retained

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-11inkopplad. He does not need to connect any equipment to the CAN bus, but can continue to use the radio communication equipment 9 to transmit suitable messages on the CAN bus via the continued connected units 4 and 9. For communication at very long distances, up to a few kilometers, it may be necessary to have targeted reception antennas in order to meet the maximum transmitted power standards. Figure 1a shows such an arrangement for radio communication units of the previously described type, 24 and 25, each equipped with a radiant transmitting antenna 24a and 24, respectively. 25a and a directional receiving antenna 24b, respectively. 25b. other equipment in Figure 1 is symbolized with 4 and 8 '.

Figure 2 schematically shows a control / control unit 201 (cf. 4 in figure 1), with one or more CPUs 202, memories 203, CPU integrated or standalone CANController 204, CAN driver 205, communication adaptation circuits 206, etc. The unit 201 is built for the CAN protocol and is connectable partly to a radio unit 208 and partly to a CAN connection 207. Radio unit 208 consists of two schematically shown communication parts, a radio communication part 209 with first hardware and software, which enables wireless communication between different radio units, and a second part with hardware and software, which includes one or more CPUs 210 , memories 211, communication adaptation circuits 212, etc. which enable communication with the unit 201. Examples of such radio units are WaveRider from GEC Plessey (GB) and examples of CAN units are CANnonBall and mini-CB from KVÄSER AB (SE). The present invention can be realized with these standard units. Radio part 208

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-12 and the CAN portion 201 each have at least one CPU and can communicate with each other via a serial or parallel interface 213. The portions 201 and 208 may be assembled in a common housing or as in the figure be applied to each housing 214 and 215, and be mutually connected with a connector 216. An advantage of having the radio unit 208 and the CAN unit 201 mounted in each housing is that the radio unit can easily be replaced in the event of a fault and replaced with a similar radio unit to comply with country or area specific rules for radio communication. The CAN portion may then be a standard unit with a parallel or serial output allowing connection to a unit corresponding to 208. If WaveRider is selected as the radio part, the interface 213 consists of eight wires for data, a so-called data bus, six wires for handshaking (three in each direction) and a wiring signal for initiating the radio at the start of the system. Each radio part has a unique identity, in the WaveRider case an Ethernet address, and each CAN unit has a unique identity, for example an EAN number including a serial number. Each unit that can be controlled also has a unique identity, such as an EAN number including a serial number.

Data transfer of an eight-byte byte from the CPU 202 to the CPU 210 is provided so that 202 activates an interrupt signal to 210 which responds with an acknowledgment signal if it is ready to receive data. (Otherwise, a signal is activated which means retry for a while.) 202 puts out a byte on the data bus and activates the signal data is available. 210 reads the bytes, acknowledges the transfer and saves it in memory 211. This is repeated until all

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-13 bytes are transferred, transfers from 210 to 202 are reversed.

Figure 3 describes a detailed embodiment of signal generation from a panel 13 of Figure 1 corresponding module, generation of message and message design and input on the bus, and receiving a module corresponding to 1. In Figure 3, only one operator unit 301 is connected to a communication unit 302 via a communication unit 302. CAN interface 303 and a communication unit 304 and a valve with control electronics 305 connected to a CANbus 306. Other modules connected to 306 are not drawn, but the total system corresponds to that shown in figure 1. Both units 302 and 304 each constitute a complete radio unit corresponding to the entire device of Figure 2, ie. the radio unit can send and receive messages both via a CANbus and via the ether. An equipment command for valve 305 (cf. 6 in Figure 1) is generated from the operator unit 301 and transmitted as a CAN message 307 to the communication unit's CAN controls which passes the data 308 on to the CPU in the CAN portion. This creates a message

309 formatted for the radio part. 309 is described in detail by 310 having the following byte sequence: An overhead block with

311 which includes suppression parts 321 and 322 where 321 consists of two bytes

311, how one of many bytes message two byte sequence number later multiple transmit consists of

312 (for radio messages), a six byte long destination address 313, a six byte long send address 314, two bytes 315 indicating how many bytes of user data 316 follows, and the portion 322 consisting of two or three bytes 317 ending the string. User data 316 is the same as 308. The CPU i

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The -14 radio part handles the incoming string and converts it into a radio message 318 with the required overhead 319 for establishing and synchronizing the radio transmission as well as 320 for terminating the sequence and ensuring that it was correct with the CRC check sum, etc. The radio overhead includes the information 321 and 322. The radio module in communication unit 304 receives the string 318 and recreates the string 310 which is transmitted to the CAN unit CPU which extracts 323 and creates the information to the CAN controller which in turn outputs the CAN message 324 on the CAN connection 306. The valve unit 305 now receives the command via the CAN connection and executes its the operator can verify.

The invention is not limited to the embodiment shown by way of example, but may be subject to modifications within the scope of the following claims and the inventive idea.

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- For 5 P.ans. No. 9600653-1