EP1301913A1

EP1301913A1 - Data transmission method

Info

Publication number: EP1301913A1
Application number: EP01955252A
Authority: EP
Inventors: Björn MAGNUSSEN
Original assignee: Siemens AG
Current assignee: Siemens AG
Priority date: 2000-07-17
Filing date: 2001-07-16
Publication date: 2003-04-16
Also published as: CN1459084A; US20030196000A1; DE10034693A1; WO2002007123A1; JP2004504742A

Abstract

According to the invention, data of several sensors (PIC1, PIC2) is transmitted to a control device (1) via a data bus (6), whereby a data relevance value is established in the sensor (PIC1, PIC2). Said data relevance value of the sensor (PIC1, PIC2) is stored on the bus (6) and only one single largest value of at least sensor (PIC1, PIC2) is transmitted to the control device (1).

Description

description

Data transmission procedures

The invention relates to a method for transmitting data from a plurality of sensors to a control device, which is used, for example, in robotics. In this case, data from sensors, for example collision sensors and tactile sensors or touch sensors, are transmitted to the control device of a robot and give this information about whether the robot has come into contact with an object.

Since a collision generally represents an event that should be avoided by the other senses of the robot, such a collision message represents important and safety-relevant information, the rapid transmission of which is desirable. Especially when using a robot in the environment of people, fast and secure transmission is of priority for reasons of safety.

It can also be important to find out the exact location or location at which the collision occurred. For this reason, robots often have a very large number of sensors, and disadvantageously, safe and fast transmission is only guaranteed at high costs.

Both the costs for the microcontrollers normally used in the sensors and the costs for the transmitting and receiving device of the sensors and possibly also the control device, that is to say the switch-on device for the communication lines, which are usually available in the form of driver modules, must be factored in here become. For this reason, cost-effective driver modules for the microcontrollers are used in most known systems, each sensor with the control unit. is individually wired to ensure safe and fast transmission of the sensor data.

As an alternative to this, the sensors can be connected to the control device via a bus system, such bus systems rarely being used in practice, since the high speed requirements mean that very expensive interface modules have to be used, so that this solution is disadvantageously cost-intensive for use in large field operation. is intensive.

The present invention is therefore based on the object of providing a method and a circuit arrangement therefor for transmitting data from a plurality of sensors to a control device which is reliable and fast

Transmission of information data about an event that has occurred, for example a collision, is guaranteed.

This object is achieved with a method with the features of claim 1 and a circuit arrangement with the features of claim 5.

According to the invention, it is possible to use both inexpensive transmission and reception devices, that is to say interface modules such as driver modules, and sensors with inexpensive microcontrollers, and in addition to avoid complicated and cost-intensive cabling by means of individual lines.

By using the method according to the invention, it is also possible to use an inexpensive, slower bus system instead of a fast, cost-intensive bus system. By transmitting the most relevant information, which prevails against less relevant information on the bus, it is achieved that this information is of sufficient speed and security for control purposes. tion facility exists and appropriate reactions can be initiated.

In a preferred embodiment of the invention, the data bus is designed as a single logical data line, via which all sensors communicate with the control device both on the receiving side and on the transmitting side. This logical individual data line can advantageously be configured physically in the form of a two-line system, the differential voltage between two lines functioning as a logical data line, so that this configuration can advantageously ensure very interference-free data transmission.

In an advantageous embodiment of the invention, the sensors begin to place their respective data relevance value, for example the detected pressure value of a collision, on the bus in synchronism with one another via their transmission output and an interface module. At the same time, the sensors listen to the corresponding signals with their receive input on the bus.

Of course, this synchronization can take place via appropriate protocols, for example a start bit, in particular a negative clock edge, which is detected by all sensors that are listening on the bus or via the control device, for example in the form of a PC, which generates a special control bit or signal on the bus , respectively.

In a preferred embodiment of the invention, the sensors only begin to place their respective data relevance value on the bus when the control device requests it, that is to say when it receives a specific signal or signal sequence, for example a byte with specific information.

On the bus, which in the preferred embodiment of the invention is designed as a "0" dominant bus, each sensor sends its data relevance value, for example in the form of a Bytes until it detects a "0" on the receive side of the bus and a different value, ie a "II11 I!" Value left.

If the values in the sensors are positively binary, for example coded as a byte and the bus is "0" dominant, these values must be inverted for the most relevant value to be enforced. Of course, the storage of the data relevance values in negative coding in the sensors or their microcontrollers or a bus system with "l" dominant behavior is also conceivable.

After the data relevance value has been transmitted, in order to determine the location or location of a collision in an advantageous manner, a unique ID of the sensor or sensors with the most relevant value can be transmitted to the PC as further information, for example as the next byte, for determination of a single sensor with the greatest importance, the transmission of the ID values can be carried out according to the same principle as described above for the data relevance values. For this purpose, the ID values are advantageously assigned to the sensors in a decreasing or increasing order according to the importance of the locations at which the sensors are located, so that the most important ID value and thus the most relevant point with the most relevant pressure value in turn prevails on the bus and is transmitted to the control device.

In this way, it is advantageously possible to transmit a fast and safe transmission of the important event, for example the most relevant pressure in the event of a collision, to a control device despite the use of the cheapest electronic components and inexpensive cabling. In a further embodiment of the invention, several or all of the pressure values of the sensors can be transmitted to the control device in the order of their relevance, the sensor with the highest data relevance value in each case switching off after its transmission to the control device, for example by setting its data relevance value to "0" and the above steps for transmitting the data relevance values of the other sensors are repeated.

This can be done repeatedly depending on a threshold value that can be predetermined on the PC, until data transmission or the query of the sensors is set when this threshold value is undershot, wherein if the threshold value is set to "0", a query of all sensors is also possible.

In the event of another collision, the sensors or their microcontrollers can then automatically overwrite the value set to "0" with the newly detected value, wherein it is also conceivable that the sensors or their values can be reset by transmitting a special signal, for example a specific byte, from the control device to the sensors.

In a special embodiment of the invention, the control unit can check the accessibility of the sensors via the bus, for example at regular intervals or on request, the sensors sending a date, for example their self-test signal, to the bus on request by the control device the control unit is evaluated. In this way, errors, such as defective sensors or errors in the transmission path, can be detected fully automatically and, if a value that is unique for each sensor is transmitted, can also be localized. Of course, it is conceivable that the sensors or their microcontrollers generate data relevance values depending on the severity of a collision at the location of this sensor and depending on certain relevance parameters of a linear or non-linear type in order to emphasize the importance of the pressure strength in a collision at certain points, such as the inclusion of a different sensitivity of different places or the like, to optimally adapt.

Further advantageous embodiments of the invention result from the dependent claims.

The invention is explained below with reference to an embodiment shown in the drawing. The drawing shows:

Fig. 1 is a schematic diagram of a circuit arrangement according to the invention and

FIG. 2 shows a diagram of a communication protocol of a circuit arrangement according to FIG. 1

1 shows how two sensors

PIC 1 and PIC 2 communicate with a control device 1, for example in the form of a PC, via a bus 6. Of course, 6 additional sensors in the form shown for PIC 1 and PIC 2 can be connected to this bus, with only the function and interaction of sensors PIC 1 and PIC 2 with control arrangement 1 being explained below to explain the circuit arrangement and the transmission method ,

The bus 6 is shown in the basic circuit diagram according to FIG. 1 as a logical data line, this logical data line being of course physically different Embodiments of how one-wire line with voltage difference compared to ground, two-wire line with voltage difference between the two lines, CAN bus, etc. can be implemented.

The circuit arrangement according to FIG. 1 can be used, for example, for a robot to enable communication between its sensors PIC 1, PIC 2, for example touch collision or tactile sensors, with its control device 1, for example in the form of a PC.

As shown in the basic circuit diagram, the receive inputs RX of the control device 1 and the sensors PIC 1 and PIC 2 are directly on the bus 6, which is connected via a resistor 7 to an energy supply (for example 5 volts).

The transmit outputs TX of the control device 1 and of the sensors PIC 1 and PIC 2, on the other hand, access the bus via interface modules 3; 5, 11; 13 and 17; 19 to. These interface modules each comprise a transistor (5, 13, 19), for example a MOS-FET, the control input of which, for example, has a gate via an inverter 3, 11, 17 with the transmit output TX of the control device 1 or the sensors PIC 1, PIC 2 is connected.

The inversion by the inverters 3, 11 and 17 is intended to make it possible for a positive signal at the output TX, that is to say a logic “1” on the bus 6, to also result in a logic “1”. This is necessary in the exemplary embodiment, since the illustrated transistor circuit of transistors 5, 13, 19 with a logic "1" at its control input, for example gate or base, the gate-source or collector-emitter path is switched through, so that the This pulls bus 6 to ground 9, ie logically "0".

In order to cancel this inversion as a result of the transistors 5, 13 and 19 and their interconnection, the control input is used each of the transistors 5, 13 and 19 is preceded by an inverter 3, 11 and 17, so that the negation of the transistors 5, 13 and 19 is canceled by this double negation and the same signal on the bus 6 as on an output TX of the control device 1 or the sensors PIC 1 and PIC 2 are present.

Of course, this principle of the interface modules 3; 5 or 11; 13 and 17; 19 is only an example of known driver blocks that can be used on the transmit side (TX) and on the receive side (RX).

The block diagram shown shows that this is a "0" dominant bus, that is to say a bus on which a logical "0" or low level prevails over a logical high or a logical "1" , since the entire bus is pulled to this low level by a single connection to ground 9.

Furthermore, the control device 1 and the sensors PIC 1 and PIC 2, which usually each have a microcontroller, are located on the reception side with their receive inputs RX on the bus 6, so that the respective state of the bus 6 is transmitted both by the control device 1 and by the Sensors PIC 1 and PIC 2 are received or detected.

In this way it is possible that not only the control device 1 and the sensors PIC 1 or PIC 2 mutually receive a transmitted signal, for example a logical "0", but also a sensor, for example PIC 1 or PIC 2, the signal of or the other sensors, for example PIC 2 or PIC 1. In this way, a sensor PIC 1 or PIC2 can determine, for example, whether another sensor PIC2 or PIC1 puts a logical "0" on the bus 6. The function of the circuit arrangement according to FIG. 1 is explained below on the basis of the communication protocol shown in FIG. 2.

If the events PIC1 and PIC2 the events registered there or their values, for example a pressure value of a collision of a robot, are to be transmitted to the control device 1, the date of a sensor, which is present, for example, in the register of a microcontroller of the sensor, is transmitted via the respective interface group 11; 13 and 17; 19 placed on the bus 6.

Since the sensors PICl and PIC2 contain pressure values from a collision and the most relevant value, i.e. the highest pressure, is to prevail, the values or pressure values contained in the sensors are negated before transmission, for example in the microcontroller, or if the Byte transmission linked with FF (binary 1111 1111) EXOR.

This results, for example, for a pressure value 63 (decimal) of the sensor PIC 1, which corresponds in binary representation 0011 1111, to the negated value 1100 0000, as shown in the top line in FIG. 1 as a rectangular signal. The pressure value 72 (decimal) of the sensor PIC 2 , which corresponds to binary 0100 1000, becomes 1011 Olli as shown in the middle line in FIG. 1 as a square wave signal.

After a start signal (a logical "0" or negative or positive clock edge), which is used, for example, to synchronize the transmission of the information from the sensors PICl and PIC2 to the control device 1, the respective pressure value of a sensor PICl is subsequently and simultaneously and PIC2 bit by bit in order 7-6-5-4-3-2-1-0 on bus 6.

Since the bus 6, as stated above, is "0" dominant, a logic "0" of a sensor PICl or PIC2 is set so that the first logical "0", as in the example bit 6 of sensor PIC2, asserts itself on bus 6. This logical "0" is determined not only by the control device 1 but also by the other sensor PIC 2 or other sensors on the bus via its receive inputs RX.

If this value (logically "0") differs from the bit value sent for this time at the output TX of a respective sensor, then this sensor stops sending. Such logic for determining such a case of "0" at the RX input and a different value at the TX output can be implemented, for example, by means of a gate or in the form of a microprogram of a microcontroller. In the example according to FIG. 2, the sensor PICl consequently stops transmitting, although this is not evident in the program, since, for reasons of better understanding, the pressure values stored in the sensors PIC 1 and PIC 2 and not those at the outputs TX or Signal lying on the bus 6 are logically represented.

After the sensor PICl stops transmitting during the transmission of the bit 6, the subsequent bits 5 to 0 of the sensor PIC2 can be transmitted via the bus 6 to the control device 1 or its input RX regardless of the value contained in the sensor PICl.

Accordingly, the highest value, ie the most relevant value of one or more sensors, also prevails in a circuit arrangement with any number of sensors. It is conceivable that the highest value is present identically in several sensors, so that although it is possible to make a statement about the highest value or the most relevant value, which according to the invention is transmitted quickly and reliably to the control device 1, it is not known in which or in which sensors this value is present. As a result, the place or location of the occurrence of such a value is not known at this time. However, this is possible in a simple manner by transmitting an ID value that is unique to a sensor, for example again in the form of a byte, subsequently for transmitting the pressure value, in which, as described above for the highest pressure value, only a certain, for example, the highest ID value is enforced.

After this transmission, which can also be synchronized again by means of a start bit, the control device 1 then knows not only the most relevant value but also the location or location of its occurrence. For this purpose, the query of an ID or an overall query "pressure value and ID" can be repeated until no sensor transmits.

In this case, it is necessary for a sensor with the most significant ID and thus in turn the most relevant value to switch off after transmission of its value to the control device 1 or to stop transmitting in the case of further ID queries.

This can take place, for example, in that the sensor PIC2, whose data relevance value and ID have been transmitted to the control device 1, sets its data relevance value to the lowest value (for example 0000 0000 and thus inverted 1111 1111). This sensor is surpassed in the next request for data in the data relevance value and thus in the assertiveness on the bus, so that the next higher value (of another sensor PICl) prevails and reaches the control device 1. In this case, a sensor can determine the successful enforcement or successful transmission of its data relevance value (DR value) and possibly ID value by permanently "listening" with its receive input RX on bus 6, so that this sensor (for the subsequent shutdown or Zeroing the register) is known that only he has prevailed on the bus 6 against the other sensors. This is explained in more detail using the following example with three sensors connected to bus 6 and synchronous transmission:

First query by control system 1:

Sensor 1:

DR value: 0000 0110 inverted: 1111 1001 sent: 1111 1001

ID value: 0000 0101 inverted: 1111 1010 sent: 1111 1010 This sensor asserts itself when sending on bus 6. The values on bus 6 correspond to those that the sensor wanted to send. So the sensor knows that it was the "winner" of this transmission. After this transfer, this sensor sets its data relevance value (DR value) to 0000 0000.

Sensor 2:

DR value: 0000 0101 inverted: 1111 1010 sent: 1111 1011 ID value: 0000 0110 inverted: 1111 1001 sent: 1111 1111 This sensor notices that its DR value was too low. It withdraws from bit 1 (second digit from the right, see sensor 1) of the DR value from bus 6 and only sends "1" (or 11 ...), especially for the entire ID value.

Sensor 3: DR value: 0000 0101 inverted: 1111 1010 sent: 1111 1011 ID value: 0000 0100 inverted: 1111 1011 sent: 1111 1111 This sensor notices that its DR value was too low. It withdraws from bus 6 from bit 1 of the DR value and only sends "1", especially for the entire ID value.

Values received on the PC or control device 1: DR value: 1111 1001 inverted: 0000 0110 = pressure value from sensor 1 ID value: 1111 1010 inverted: 0000 0101 = ID value of sensor 1

Query of the second most relevant value Sensor 1:

DR value: 0000 0000 inverted: 1111 1111 sent: 1111 1111 ID value: 0000 0101 inverted: 1111 1010 sent: 1111 1111 This sensor notices that its (reset) DR value was too low. It withdraws from bit 2 (third digit from the right, see sensors 2 and 3) of the DR value from bus 6 and only sends "1", especially for the entire ID value.

Sensor 2: DR value: 0000 0101 inverted: 1111 1010 sent: 1111 1010 ID value: 0000 0110 inverted: 1111 1001 sent: 1111 1001 This sensor asserts itself when sending on bus 6. The values on bus 6 correspond to those that the sensor wanted to send. So the sensor knows that it was the "winner" of this transmission. After this transfer, this sensor sets its data relevance value (DR value) to 0000 0000.

Sensor 3:

DR value: 0000 0101 inverted: 1111 1010 sent: 1111 1010 ID value: 0000 0100 inverted: 1111 1011 sent: 1111 1011 This sensor notes that its DR value was high enough to be sent successfully. He knows that no other sensor has a higher data relevance. However, it may still be that another sensor has the same DR value (as in this example). In order to resolve the situation, the ID value is transmitted. This sensor detects that another sensor with the same DR value has a stronger ID. This is why this sensor withdraws from bus 6 from bit 1 of the ID and only sends "1".

Values received on the PC or control device 1: DR value: 1111 1010 inverted: 0000 0101 = pressure value from sensor 2 ID value: 1111 1001 inverted: 0000 0110 = ID value of sensor 2

Querying the third most relevant value: Sensor 1:

DR value: 0000 0000 inverted: 1111 1111 sent: 1111 1111 ID value: 0000 0101 inverted: 1111 1010 sent: 1111 1111 This sensor notices that its (reset) DR value was too low. It withdraws from bit 2 (third digit from the right, see sensor 3) of the DR value from bus 6 and only sends "1", especially for the entire ID value.

Sensor 2:

DR value: 0000 0000 inverted: 1111 1111 sent: 1111 1111 ID value: 0000 0110 inverted: 1111 1001 sent: 1111 1111 This sensor notices that its (reset) DR value was too low. It withdraws from bit 2 (third digit from the right, see sensor 3) of the DR value from bus 6 and only sends "1", especially for the entire ID value.

Sensor 3:

DR value: 0000 0101 inverted: 1111 1010 sent: 1111 1010 ID value: 0000 0100 inverted: 1111 1011 sent: 1111 1011 This sensor asserts itself when sending on bus 6. The values on bus 6 correspond to those that the sensor wanted to send. So the sensor knows that it was the "winner" of this transmission. After this transfer, this sensor sets its data relevance value (DR value) to 0000 0000.

Values received on the PC or control device 1: DR value: 1111 1010 inverted: 0000 0101 = pressure value from sensor 3 ID value: 1111 1011 inverted: 0000 0100 = ID value of sensor 3

Querying the fourth most relevant value:

Sensor 1: DR value: 0000 0000 inverted: 1111 1111 sent: 1111 1111 ID value: 0000 0101 inverted: 1111 1010 sent: 1111 1011 All sensors recognize that they have the highest possible DR value, but do not know how many other sensors have the same value. When sending the ID, the sensor with the strongest ID prevails. From bit 1 of the ID, this sensor recognizes that another sensor is stronger (or has a stronger ID) and only sends "1" from there.

Sensor 2:

DR value: 0000 0000 inverted: 1111 1111 sent: 1111 1111 ID value: 0000 0110 inverted: 1111 1001 sent: 1111 1001 All sensors recognize that they have the highest possible DR value, but do not know how many other sensors have the same value. When sending the ID, the sensor with the strongest ID prevails. This sensor recognizes that its ID has prevailed on the bus.

Sensor 3:

DR value: 0000 0000 inverted: 1111 1111 sent: 1111 1111

ID value: 0000 0100 inverted: 1111 1011 sent: 1111 1011 All sensors recognize that they have the highest possible DR value, but do not know how many other sensors have the same value. When sending the ID, the sensor with the strongest ID prevails. From bit 1 of the ID, this sensor recognizes that another sensor is stronger (or has a stronger ID) and only sends "1" from there.

Values received on the PC or control device 1: DR value: 1111 1111 inverted: 0000 0000 = minimum DR value ID value: 1111 1001 inverted: 0000 0110 = ID value of sensor 2 The PC recognizes that the ID of the Sensor 2 has now been sent for the second time. This means that all sensors have been read out. This can also be seen from the data relevance value, since the lowest possible DR value (0000 0000) must not be the result of a pressure measurement. In order to make this recognizable, a "1" can always be added for each measured pressure. The ID transmission, like the pressure value transmission, can take place on request from the control device 1, for example by transmission of a start signal in the form of a bit, negative or positive clock edge, special bytes or the like.

However, it is also conceivable that the sensors PICl PIC2 etc. begin to send on their own as soon as at least one sensor PICl, PIC2 detects a collision and applies a negative clock edge or a low-level signal to the bus 6, which of the other sensors is detected as a start bit, so that all sensors PIC1, PIC2, etc. on the bus 6 begin to transmit their contained pressure values synchronously at the same time. Of course, it is also conceivable that only those sensors that actually detected a collision begin to transmit.

In a preferred embodiment of the invention, the ID transmission takes place without renewed synchronization, the synchronization being used for DR value or pressure value transmission and a fixed time delay taking place before the start of the ID transmission. Typically, the sensors PIC1, PIC2 measure the time of the start bit (Ts), for example, sent by the control device 1, for example a first byte sent, and respond with the synchronized (simultaneous) transmission of the DR values at a specified time thereafter (Ts + Tl). In the following, the sensors PICl, PIC2 require no further synchronization and transmit with a defined delay

(TS + T1 + T2) their ID value. As a result, re-synchronization between the transmission of the DR values and the transmission of the ID values is not necessarily necessary. However, if the time base of the sensors is bad, the sensors can wait a defined time and then start sending a start bit to synchronize the transmission of the ID values. Here, the waiting process, rend the sensors listen to the bus 6 for occurring start bits, are aborted, and thus (re) synchronization is achieved.

For the fast data transmission according to the invention between the sensors PIC1, PIC2 and the control device 1, inexpensive, commercially available components (in mass production, for example RS485 or CAN drivers from Philips) can advantageously be used.

The data transmission can take place via the well-known inexpensive standard RS232, whereby an inexpensive bus system with only one logical data line and inexpensive customary interface modules or bus driver modules can be used to control several sensors on a bus, for example according to the wired AND principle connect to. In particular, a conventional RS232 protocol can be used as the data protocol on the control device 1 side, so that this system can advantageously be connected to many existing PCs or other equipment with RS 232 without a protocol converter (but possibly with level converter).

It is also possible to use inexpensive sensors, for example with a microcontroller, in this circuit arrangement, since the principle according to the invention, in which the most relevant value prevails first and only on the bus and is thus transmitted to the control device 1, despite the cost-effective implementation of the circuit - order a sufficient speed and security is guaranteed.

Of course, other functions such as resetting the sensors, for example the register of the microcontrollers, calibrating the sensors PICl and PIC2, etc. can also be implemented in this system with the lowest cabling effort and cost-effective electronic components. It is thus possible, at the request of the control device 1, for example by transmitting a special byte

(of course different from the request byte) a reset of the sensors PICl, PIC2 as well as a calibration process by transmitting another special byte

(e.g. the time base and / or the sensor sensitivity or the mathematical function according to which a pressure value is calculated in the sensor) o.a. trigger.

It is also conceivable, for example, to test the functionality of the entire system, in which the pressure values and / or the unique ID values are transmitted to the control device 1 without a collision, and in this way the functionality of all sensors PIC, PIC2, etc. and the like Transmission path can be checked.

In order to optimally adapt the value of the sensors PIC1, PIC2 to the respective use, it is also conceivable not only to distribute the ID values according to the relevance of the locations or locations of the sensors, for example in descending order, but also to determine a collision value in to couple a sensor PIC 1, PIC 2, etc. with an adjustable relevance value in a linear or non-linear function, so that a pressure value for a collision arises depending on this relevance value and the function and the actual sensor value, which is then transmitted to the control device 1 becomes.

According to the invention, it is also conceivable to address specific sensors in a targeted manner by transmitting the ID of the sensor. In this case, the control device 1 first sends a command (eg "send self-information") and then the ID of the desired sensor, while all other sensors are not involved in this transmission. Furthermore, a “self-mode” can be integrated in the arrangement and the method, in which the sensors send a break signal that is dominant to all other transmissions (for example in the RS232 protocol) when a certain event occurs (for example 0 0000 0000 0000 0000). Each sensor can be equipped with a reaction threshold that can be set by the control device 1. If the reaction threshold (data relevance threshold) is exceeded for a sensor after the sensors have been switched to the "self-reporting mode", then it sends itself (without request from the control device 1), for example 0000 0000. Even if several sensors are sent at the same time, the result is either 0000 0000 again or a longer period that can also be recognized by the control device 1 (eg break signal according to RS232 protocol). If sensors receive a 0000 0000 via their receive input RX, they return to the normal communication mode described above. Accordingly, it is not necessary for control device 1 to have the value (for example collision pressure) of a sensor or of all connected sensors

Sensor continuously polls, but can wait until a signal arrives at the serial interface (RS232). If the control device 1 has received such a signal, it asks for the strongest or most relevant pressure value using the method described above. It is also possible here for the control device 1 to terminate this “self-reporting mode” prematurely, for example by sending 0000 0000 itself.

It is also conceivable that a sensor that has not been queried for a certain predeterminable period of time can make itself noticeable with longer 0 periods. This signal is then received by the control device 1 as a break signal independently of other processes.

By the method described above for a robot and collisions, the principle according to the invention The transmission of data depending on their relevance thus ensures, with the most cost-effective implementation, that at least the relevant value or values are available with sufficient speed and security at the control device 1 for further processing.

Of course, the method according to the invention and the circuit arrangement are not limited to the exemplary embodiment shown, but can be used in a wide variety of fields of application in which objects execute relative movements to one another, distances are to be determined, collisions are to be avoided, or also in stationary systems such as, for example Sensors for measuring earthquakes, wind speeds, etc. and transmitting this data to central control devices.

In this case, by means of the competition described above, the importance or relevance of the data from the sensors to one another and the enforcement (depending on this competition and consequently dynamically) of the most relevant value of the sensors which are transmitting or are located on a bus can be achieved in comparison with This information is available more quickly to conventional systems, so that, advantageously, slower, simpler and more cost-effective systems for transmission (bus systems, interface modules, sensors, etc.) can also be used. Here, sensors in the sense of the invention are to be understood very broadly and also include, for example, input devices with at least one receive input RX and at least one transmit output TX.

It is expressly pointed out that, according to the invention, the strongest data relevance value of all sensors connected to the bus asserts itself in the synchronous or simultaneous transmission of the (sensor) values and that the data value is or is contained in this data relevance value Data relevance value depends on the data value and a parameter function. The relevance or priority during the transmission is thus dependent on the data itself, which according to the invention is to be understood as variable or dynamic relevance or priority of the data.

Claims

claims

1. Method for transmitting data from a plurality of sensors (PICl, PIC2) to a control device (1) via a data bus (6), wherein

a) a data relevance value is determined in the sensor (PICl, PIC2),

b) the data relevance value of the sensor (PICl, PIC2) is placed on the bus (6) and

c) only the largest data relevance value of the sensors (PICl, PIC2) is transmitted to the control device (1).

2. The method according to claim 1, characterized in that the data relevance value of the sensor (PICl, PIC2) in the event of a detected event on the sensor (PICl, PIC2) and / or at the request of the control device (1) or another sensor (PICl, PIC2) is placed on the bus (6).

3. The method according to claim 1 or 2, characterized in that following step c), d) an ID value of the at least one sensor (PICl, PIC2) is placed on the bus (6) and only a single most relevant ID value is transmitted to the control device (1).

4. The method as claimed in claim 3, characterized in that steps a) to d) are repeated for as long as the sensor (PICl, PIC2) whose ID value has been transmitted stops transmitting until it is sent to the control device ( 1) transmitted values lie below a predeterminable threshold value.

5. Circuit arrangement for performing the method according to one of the preceding claims, with a plurality of sensors (PICl, PIC2), a data bus (6) and a control device device (1), characterized in that the sensors are connected to the control device (1) via the data bus (6) in a wired-AND principle, so that only one date of a sensor (PICl, PIC2) is established.

6. Circuit arrangement according to claim 5, characterized in that the sensor (PICl, PIC2) has a transmit output (TX) and a receive input (RX) which are connected to the bus (6) by means of interface modules (3; 5, 11; 13, 17; 19) are connected, and have a control device which, in the case of different signals at the transmit output (TX) and receive input (RX), occupies the transmit output (TX) with a neutral signal (logical "1").

7. Circuit arrangement according to claim 5 or 6, characterized in that the bus (6) comprises only one logical data line.

8. Circuit arrangement according to one of claims 5 to 7, characterized in that the bus (6) is "0" dominant, "1" dominant, or is designed as a wired OR.

9. Circuit arrangement according to one of claims 5 to 8, characterized in that the bus (6) is designed electrically as a CAN bus.

10. Circuit arrangement according to one of claims 5 to 9, characterized in that each sensor (PI1, PIC2) has a unique ID value which can be transmitted to the control device (1).

11. Circuit arrangement according to one of claims 5 to 10, characterized in that the control device (1) is RS232 compatible.