DEVICE FOR MONITORING THE POSITION AND/OR ATTITUDE AND/OR MOVEMENT OF A TOOL

Abstract

The invention relates to a device for monitoring the position and/or location and/or movement of a tool to which an inertial sensor, such as a gyroscope sensor and/or an inertial sensor, is attached. A monitoring unit is provided in order to determine the position and/or location and/or movement of the tool on the basis of a specified starting situation using the detected sensor data. The device is characterized in that in order to calibrate the sensor (s), at least one image capturing unit is provided which is designed to capture one or more images of the tool at least at specified points in time or in intervals; an image analysis unit is provided for determining the position and/or location and/or movement of the tool; and the monitoring unit is designed to calibrate the sensor data in order to process the data.

Claims

1. A device having a tool for monitoring the position and/or attitude and/or movement of the tool, the tool having an inertial sensor such as a gyroscope sensor and/or an inertia sensor mounted on it, further comprising a supervisory unit, at least one image capture unit and an image evaluation unit, wherein the supervisory unit is designed to determine a position and/or an attitude and/or a movement of the tool, starting from a specified initial situation, on the basis of the captured sensor data from the inertial sensor, wherein the image capture unit is provided for calibrating the inertial sensor, the image capture unit being designed to capture one or more photographs of the tool at least at specific times or in specific time intervals, wherein the image evaluation unit is provided for determining the position and/or attitude and/or movement of the tool, and wherein the supervisory unit is designed to calibrate the sensor data from the inertial sensor in order to process the data from the image capture unit, wherein the device further comprises a locating device, the locating device being designed to have an ultrasonic transmitter and an ultrasonic receiver, the locating device being designed to locate the tool by determining the distance between the ultrasonic transmitter and the ultrasonic receiver by way of time-of-flight measurements on ultrasonic signals, the ultrasonic signals being able to be used to determine the distance between applicable transmitters and receivers, wherein the work area of the locating device operating by means of time-of-flight measurement stretches beyond an image area of the image capture unit and there is provision for the presence of the tool in the image area of the image capture unit to be detected by the locating device in order to locate the tool by way of time-of-flight measurements on the ultrasonic signals.

2. The device as claimed in claim 1, wherein the supervisory unit is designed so that the data from the inertial sensor are matched against those from the image processing, and/or the inertial sensor is calibrated, when the tool is in the image area of the image capture unit.

3. The device as claimed in claim 1, wherein the supervisory unit is designed so that the data from the inertial sensor are regularly matched against those from the image processing, and/or the inertial sensor is calibrated, when the tool is in the image area of the image capture unit.

4. The device as claimed in claim 1, wherein the locating device comprises electromagnetic sensors.

5. The device as claimed in claim 1, wherein the device further comprises a data transmission unit, the data transmission unit being designed not only for the data transmission of data from the inertial sensor but also for the data transmission of and/or of other data/information/parameters, in particular to transmit a trigger signal from the locating transmitter.

6. The device as claimed in claim 1, wherein the tool is a handheld tool such as a screwdriver, a drill or the like.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0040] An exemplary embodiment of the present invention is shown in the drawing and is explained in more detail below with reference to the figures, in which, specifically,

[0041] FIG. 1 shows a schematic representation of an assembly line with a device according to the present invention;

[0042] FIG. 2 shows a block diagram of a device according to the present invention; and

[0043] FIG. 3 shows a schematic representation of a locating device with an item to be located.

DETAILED DESCRIPTION OF THE INVENTION

[0044] FIG. 1 schematically shows an assembly line 1 that has an upper run 3 running around a deflection roller 2. Semifinished automobiles 4, 5 are shown on the assembly line 1 as workpieces to be worked on according to the present invention.

[0045] Each of the automobiles 4, 5 or workpieces has an associated locating device 6, 7, each of which is moved along on the assembly line 1 at a fixed location in relation to the applicable workpiece 4, 5. The workpieces may alternatively also be arranged on self-propelled assembly islands.

[0046] Each locating device 6, 7 comprises three locating sensors 8, 9, 10 and a communication unit 11 for wireless communication by means of electromagnetic waves 12, for example, as a data transmission unit as mentioned above.

[0047] Three schematically represented different items to be located in the form of a screwdriver 13, a glove 14 and an assembly part 15 are each likewise provided with locating sensors 16, inertial sensors 17, 18 and a communication unit 19.

[0048] FIG. 2 shows a central supervisory unit 20 that, by means of a communication unit 21, includes a data connection to locating devices and items to be located.

[0049] It is additionally connected to a control unit 22, a display 23 and a signal transmitter 24.

[0050] FIG. 3 shows the locating device 7 and the screwdriver 13 as an item to be located. The screwdriver 13 includes the locating sensors 25, 26, 27, a communication unit 28 and two inertial sensors 29, 30. By way of example, one of the inertial sensors 29 may be an inertia sensor for measuring impulse changes and the other inertial sensor 30 may be a gyroscope.

[0051] To calibrate the inertial sensors 29, 30, there is provision for an image capture unit, which is connected via a wireless data channel 32 to an image evaluation unit 33, which in turn communicates with the central supervisory unit 20.

[0052] As an example of the locating method, a path 1 is shown that can be used to measure the time of flight of a locating signal. As such, for example, the locating sensor 10 may be in the form of an ultrasonic transmitter and the locating sensor 25 may be in the form of an ultrasonic receiver. By way of example, one option for the time-of-flight measurement is for the central supervisory unit 20 to use the communication unit 21 to send a trigger signal to the locating device 7 and to the item to be located 13. As a result, the locating sensor 10 outputs an ultrasonic signal that, after travelling along the path 1, is detected by the locating sensor 25. In one embodiment of the present invention, receipt of the ultrasonic signal is acknowledged by way of the communication unit 28, and so the central supervisory unit 20 ascertains the time of flight. In another embodiment, the trigger signal can be used to start a clock in the locating sensor 25, and so receipt of the locating signal immediately results in the time of flight being measured and said time of flight being transferred as information by way of the communication unit 28.

[0053] In principle, location or time-of-flight measurement can also take place in a different direction, that is to say that the locating sensor 25 may be in the form of the transmitter and the locating sensor 10 may be in the form of the receiver.

[0054] In each of the variant embodiments shown, three locating sensors are mounted on the items to be located. This allows not only the position of the respective item to be located 13, 14, 15 but also the orientation thereof in space to be ascertained, which may be advantageous for the intended process monitoring. Location and determination of the orientation of an item to be located 13, 14, 15 would also be possible with only one locating sensor in combination with an inertial sensor.

[0055] As can be discerned from FIG. 1, there is provision at each workpiece 4, 5 for a locating device 6, 7 mounted at a fixed location in relation to the workpiece 4, 5. By way of location of an item to be located 13, 14, 15 and possibly the orientation of the item, the relative position of the item to be located in relation to the workpiece 4, 5 and the orientation with respect thereto are thus immediately known. It is, therefore, possible for the movements of the items to be located 13, 14, 15 in relation to the workpieces 4, 5 to be monitored by the central supervisory unit 20.

[0056] Depending on the work step to be monitored, the process support computer can receive information about the nature or type of the applicable item to be located. If required, however, an individual identification can also be carried out by way of the separate data connection. Additionally, other information, such as, for example, rotation speed, torque or the like, can also be transferred during an assembly operation. A tool detected as an item to be located can also be adjusted by the central supervisory unit 20 by way of this data connection.

[0057] Items to be located that can be put on by a member of assembly personnel, for example, the glove 14, can be used to track movements of assembly personnel. This allows the assembly movements to be monitored or the assembly personnel to be guided through the process steps that are to be performed.

[0058] Assembly parts, that is to say parts to be mounted on the workpieces 4, 5, can also be monitored as appropriate, as shown schematically using a vehicle door 15.

[0059] In one particular embodiment, the locating sensors 8, 9, 10 of the locating devices 6, 7 are equipped with transmitters for the time-of-flight signal, for example, with ultrasonic transmitters. Accordingly, the mobile items to be located 13, 14, 15 require only receivers for the time-of-flight signal. This significantly reduces the energy requirement for these mobile items. The separate data connection by way of the communication units 19 means that the items to be located can also be used with passive receiving sensors 16 for a time-of-flight measurement.

[0060] The locating devices 6, 7 arranged at fixed locations with the workpieces can be connected to larger energy stores or to a power supply grid without any problem. In principle, the separate data connection on the locating devices 6, 7 can also be made by wire to the process support computer or a similar unit having a comparable function.

[0061] It is sufficient for the flexibility of the process support device if the items to be located 13, 14, 15 are able to move freely relative to the location at which the workpieces 4, 5 are worked on.

[0062] The display 23 and the signal transmitter 24 can firstly be used to provide information about process steps performed to persons involved in the process to be monitored. A warning signal in the event of an erroneous process step can also be generated by way of these two units, for example. Process management is similarly possible by way of these units, for example, by virtue of the location of the next process step being shown or highlighted. A person who is in the process can also be audibly guided to the location of the next process step.

[0063] The image capture unit 31 is placed such that any item 13, 14, 15 to be monitored is regularly taken into the image capture area. The data from the image capture are then used to calibrate the inertial sensors 29, 30.

[0064] To this end, the image evaluation unit 33 is connected to the central supervisory unit 20, which in turn communicates with the inertial sensors 29, 30. The data processing of an inertial sensor 29, 30 can be performed in the supervisory unit or even in the sensor itself. Accordingly, the calibration then also takes place either in the central supervisory unit 20 or, following appropriate data transfer, in the applicable inertial sensor 29, 30. Data processing in the peripheral area of a network, i.e. in the present case in the sensor or sensors, is also referred to as edge computing.

[0065] The inertial sensors mean that items to be located that are connected to the process to be monitored can be used, which do not necessarily have to be constantly connected to the respective locating device. When they leave the range of the locating device, it is possible to determine the position and/or attitude and/or movement of the tool, starting from a specified initial position, on the basis of the captured sensor data from the inertial sensors 29, 30.

[0066] Preferably, the locating device is in the form of an ultrasonic locating device for detecting the item or items to be located by means of ultrasonic waves, and/or an additional and/or separate data transmission unit for transmitting process-related actual and/or target data is in the form of a radio data transmission unit for transmitting process-related actual and/or target data by means of electromagnetic waves.

[0067] By way of example, the different times of flight of firstly ultrasonic waves and secondly (much faster) electromagnetic radio transmission or electrical data transmission by means of electrical cables or electrical wired connections and/or by means of optical data line, in particular fiber-optic cables, allow an (electromagnetic) trigger signal to be used, or, when a trigger signal is sent, the time-of-flight measurement of ultrasonic location of the locating sensor or sensors, to ascertain the distance or the exact position of the item to be located and, if need be, to process them further. If necessary, the new 5G radio standard can also be used for position finding.

[0068] Instead of the assembly line 1, there may also be provision, in another exemplary embodiment, for a large workpiece such as an aircraft in assembly, there being multiple ultrasonic transmitters and receivers of a locating device in a stationary distributed arrangement around the aircraft. One or more image capture units are then distributed over the work area such that each tool to be monitored is regularly taken into an image capture area. The data from the image capture are then used to calibrate one or more inertial sensors on the tool or tools.

[0069] To this end, an image evaluation unit, not shown in more detail, is connected to a supervisory unit for the inertial sensor or sensors, which in turn communicates with the inertial sensor or sensors. The data processing of an inertial sensor can be performed in the supervisory unit or even in the sensor itself. Accordingly, the calibration then also takes place either in the supervisory unit or, following appropriate data transfer, in the sensor.

[0070] In combination with the device for ultrasonic location shown, the position and/or attitude and/or movement of the tool can be determined by way of matching against these location data. To this end, a supervisory unit of the locating device is available in combination with the supervisory unit of the inertial sensor or sensors and/or the image evaluation unit. The image evaluation unit, and the supervisory units of the locating device and/or the supervisory unit for the inertial sensor or sensors, can also be combined into one or two supervisory units or connected to a central supervisory unit.

[0071] The data from the inertial sensors can be used in combination with the location data, for example, in order to reduce the number of locating sensors or to perform data matching. However, the invention's calibration of the inertial sensors is not limited to use in combination with a locating device according to the exemplary embodiments described.

LIST OF REFERENCE SIGNS

[0072] 1 assembly line [0073] 2 deflection roller [0074] 3 upper run [0075] 4 automobile [0076] 5 automobile [0077] 6 locating device [0078] 7 locating device [0079] 8 locating sensor [0080] 9 locating sensor [0081] 10 locating sensor [0082] 11 communication unit [0083] 12 electromagnetic waves [0084] 13 screwdriver [0085] 14 glove [0086] 15 assembly part [0087] 16 locating sensor [0088] 17 inertial sensor [0089] 18 inertial sensor [0090] 19 communication unit [0091] 20 central supervisory unit [0092] 21 communication unit [0093] 22 control unit [0094] 23 display [0095] 24 signal transmitter [0096] 25 locating sensor [0097] 26 locating sensor [0098] 27 locating sensor [0099] 28 communication unit [0100] 29 inertial sensor [0101] 30 inertial sensor [0102] 31 image capture unit [0103] 32 wireless data channel [0104] 33 image evaluation unit