Sensor devices and sensor systems for monitoring machines

Abstract

The present invention relates to a sensor device (12) including a gyroscope sensor unit (20) and / or an acceleration sensor unit (22) and a wireless interface (18) for data transmission by wireless signals, as well as a sensor system (10) for monitoring a machine (1) including a plurality of such sensor devices (12). The sensor arrangement according to the invention comprises a distance determination unit (26) configured to analyze the received radio signal (FS) and to determine, based on the radio signal (FS), an antenna distance (AA) to the antenna arrangement (7) from which the received radio signal (FS) was transmitted. The determined antenna distance (AA) provides additional information on the spatial position of the sensor arrangement (12) without the need for additional sensors. This allows a relatively simple and reliable monitoring of the operation of the machine.

Description

[Technical Field]

[0001] The present invention relates to a sensor device comprising a gyroscope sensor unit and / or an acceleration sensor unit and a wireless interface for data transmission by wireless signals. The present invention also relates to a sensor system for monitoring machines, in particular construction machines such as excavators, cranes or bulldozers, which comprises a plurality of sensor devices. [Background technology]

[0002] A sensor device with a gyroscope sensor unit and / or an acceleration sensor unit is also called, for example, an angular velocity sensor, a gyro device, an accelerometer, an acceleration sensor, an acceleration meter, a periodic vibration sensor, a vibration sensor, a G sensor, a B-meter or an inertial measurement unit.

[0003] Such sensor devices and sensor systems comprising such sensor devices are frequently used to monitor the operation of machines, with the individual sensor devices of the sensor system typically being arranged in different mutually movable parts of the machine.

[0004] In this document, the term wireless interface refers to any interface that allows wireless data transmission. Typical wireless interfaces are, for example, an RFID interface, a WLAN interface, a mobile radio interface, a Bluetooth interface, or an IrDA interface.

[0005] A sensor system for monitoring the movement of an excavator is known from U.S. Patent Application Publication No. 2018 / 0372498. The sensor system comprises multiple inertial measurement units arranged on each of the mutually movable parts of the excavator. The sensor data of the multiple sensor devices are fused using complex evaluation algorithms to determine the spatial position of the excavator and its individual parts, in particular the bucket. To improve the accuracy of the sensor system, it is preferable to use multiple sensor devices in other forms, such as GPS devices, radar devices, or cameras. Summary of the Invention [Problem to be solved by the invention]

[0006] In view of this background, the object of the present invention is to make it possible to monitor the operation of a machine in a relatively simple and reliable manner. [Means for solving the problem]

[0007] This problem is solved by a sensor device having the features of claim 1.

[0008] In the present invention, the sensor device includes a distance determination unit configured to analyze the received radio signal and determine, based on the radio signal, an antenna distance to an antenna device from which the received radio signal was transmitted. For example, the distance may be determined by analyzing the propagation delay of the radio signal and / or the amplitude of the radio signal. The determined antenna distance provides additional information about the spatial location of the sensor device without requiring an additional sensor.

[0009] The additional position information allows the relative spatial positions of individual machine components to be determined relatively simply and reliably, particularly when a plurality of sensor devices according to the present invention are used in a sensor system, thereby enabling relatively simple and reliable monitoring of the machine. The additional position information also allows for correction of the measurement data of the gyroscope sensor unit and / or the acceleration sensor unit, thereby allowing the spatial orientation of the individual sensor devices, and thus of the respective machine components, to be determined particularly accurately.

[0010] The wireless data interface is preferably a 5G mobile radio interface, which allows for a direct connection of the sensor device to a relatively high bandwidth internet without the need to install additional radio base stations in the vicinity of the sensor device, while the properties of 5G radio signals allow for a relatively accurate determination of the antenna distance.

[0011] The above-mentioned technical problem is further solved by a sensor system for monitoring a machine, which comprises a plurality of sensor devices according to the invention as described above.

[0012] In the present invention, the sensor system includes a positioning unit provided with measurement data of a gyroscope sensor unit and / or measurement data of an acceleration sensor unit and antenna distances of at least two sensor devices. The positioning unit is configured to determine position data of the at least two sensor devices based on the provided gyroscope sensor unit measurement data and / or acceleration sensor unit measurement data and the provided antenna distances. The determined position data indicates the relative spatial positions of the at least two sensor devices with respect to each other. The measurement data of the gyroscope sensor unit and / or measurement data of the acceleration sensor unit typically indicate the spatial orientation of each sensor device. Based on the respective spatial orientations of the sensor devices and the respective antenna distances of the sensor devices, the position data can be determined primarily by geometric relationships. The position data indicates at least the distance between each sensor device. The position data preferably indicates relative 3D coordinates, which are 3D coordinates in machine reference system coordinates, of each sensor device. When absolute 3D coordinates, which are 3D coordinates in Earth reference system coordinates, are known for one of the sensor devices, the relative 3D coordinates can be easily converted into absolute 3D coordinates by the positioning unit or a subsequent data processing device. As no additional sensor devices are required to determine position data, the sensor system according to the invention allows for relatively simple and reliable monitoring of machine operation.

[0013] The sensor system preferably includes at least one sensor device calibration unit configured to calibrate the gyroscope sensor unit and / or the acceleration sensor unit of at least one sensor device based on the antenna distances of the at least two sensor devices. When the distance between the two sensor devices and the antenna distances of the two sensor devices are known, the spatial orientation of the two sensor devices can be determined using a geometric relationship. The gyroscope sensor unit and / or the acceleration sensor unit of each sensor device can then be calibrated so that the spatial position indicated by the measurement data of the gyroscope sensor unit and / or the measurement data of the acceleration sensor unit coincides with the spatial position determined from the distance. To ensure that the distance between the two sensor devices is known, for example, a predetermined machine state can be set. Alternatively, the distance between the two sensor devices can be detected by one or more additional sensor devices. The sensor system can include one central sensor device calibration unit. The calibration unit can be located, for example, in a central data processing device and configured to calibrate several, preferably all, of the sensor devices. Alternatively, it is also conceivable to provide each sensor device with a separate sensor device calibration unit, which is provided with the antenna distance of at least one other sensor device, and which is configured to carry out only the calibration of the respective sensor device itself, so that the distance to the at least one other sensor device is known. The sensor device calibration unit makes it possible to provide particularly accurate and reliable measurement data, thereby making it possible to monitor machines particularly reliably with the sensor device according to the invention.

[0014] The sensor system advantageously includes at least one centrifugal force compensation unit. The centrifugal force compensation unit determines the rotation axis distance to the rotation axis of the monitored machine based on the position data of at least one sensor device. Then, based on the rotation axis distance and the measurement data of the gyroscope sensor unit and / or the acceleration sensor unit of each sensor device, the centrifugal force acting on each sensor device is estimated. The centrifugal force compensation unit is further configured to correct the measurement data of the gyroscope sensor unit and / or the acceleration sensor unit of each sensor device based on the estimated force. In particular, the centrifugal force compensation unit is configured to correct the measurement data of the gyroscope sensor unit and / or the acceleration sensor unit to compensate for measurement errors caused by the centrifugal force in the gyroscope sensor unit and / or the acceleration sensor unit. To enable simple and reliable determination of the rotation axis distance, one sensor device is preferably designed to be mounted at a fixed distance from the machine rotation axis. As a result, the distance to the rotation axis can be directly derived from the distance to this sensor device. More preferably, one sensor device is designed to be mounted directly on the machine's rotation shaft so that the distance to the sensor device is substantially the same as the distance to the machine's rotation shaft. The sensor system can include one central centrifugal force compensation unit. This central centrifugal force compensation unit can be arranged, for example, in a central data processing device and is configured to perform corrections of measurement data from several, preferably all, of the sensor devices. Alternatively, it is conceivable to provide each sensor device with a separate centrifugal force compensation unit configured only to perform calibration of the respective sensor device itself. The centrifugal force compensation unit makes it possible to provide particularly accurate and reliable measurement data. This allows the sensor device according to the present invention to enable particularly reliable monitoring of machines.

[0015] An embodiment of a sensor system according to the invention having a plurality of sensor devices according to the invention will now be described with reference to the drawings. [Brief explanation of the drawings]

[0016] [Figure 1] FIG. 1 shows a schematic diagram of a sensor system according to the invention, comprising a plurality of sensor devices according to the invention arranged on an excavator, and a mobile radio antenna device. [Figure 2] 2 is a schematic top view showing the antenna distances between the individual sensor devices of the sensor system and the mobile radio antenna device, the sensor device distances between the individual sensor devices of the sensor system, and the rotation axis distances between the sensor devices and the mechanical rotation axis in the sensor system and mobile radio antenna device of FIG. [Figure 3] FIG. 3 is a schematic diagram showing the configuration of the sensor device of FIG. [Figure 4] FIG. 4 is a schematic diagram showing the configuration of the central data processing unit of the sensor system of FIG. DETAILED DESCRIPTION OF THE INVENTION

[0017] FIG. 1 shows an excavator 1 having a lower running body 2, an upper rotating body 3 rotatably supported on the lower running body about a rotation axis D, a boom 4 pivotally attached to the upper rotating body 3, an arm 5 pivotally attached to the boom 4, and a bucket 6 pivotally attached to the arm 5.

[0018] Figure 1 also shows the antenna device 7, which in this embodiment is a 5G mobile radio antenna device, meaning that it is configured to transmit and receive mobile radio signals FS in accordance with the 5G standard.

[0019] The sensor system 10 according to the present invention is arranged on the excavator 1 to detect the spatial position and spatial orientation of the excavator 1, as well as the spatial positions and spatial orientations of the individual parts of the excavator 1, namely the undercarriage 2, the upper rotating body 3, the boom 4, the arm 5 and the bucket 6.

[0020] In this embodiment, the sensor system 10 includes four sensor devices 12_1 to 12_4 interconnected via a data transmission network 14. The first sensor device 12_1 is disposed on the upper rotating body 3, the second sensor device 12_2 is disposed on the boom 4, the third sensor device 12_3 is disposed on the arm 5, and the fourth sensor device 12_4 is disposed on the bucket 6. In this embodiment, the first sensor device 12_1 is disposed directly on the rotation axis D.

[0021] 2 shows a schematic top view of the excavator 1 with the boom 4 fully extended and the arm 5 fully extended. FIG. 2 also shows schematically antenna distances AA_1 to AA_4 between the individual sensor devices 12_1 to 12_4 and the antenna device 7, sensor device distances SA_12, SA_23, SA_34 between adjacent sensor devices 12_1 to 12_4, as well as the rotation axis distance DA_4 between the fourth sensor device 12_4 and the rotation axis D, for example.

[0022] The configuration of the sensor devices 12_1 to 12_4 is shown schematically in Fig. 3. Since the sensor devices 12_1 to 12_4 in this embodiment have essentially the same structure, in Fig. 3 and the following description, generic reference numbers, which are reference numbers without indexes 1 to 4, are used for simplicity only when it relates to all of the sensor devices 12_1 to 12_4 or any one of the sensor devices 12_1 to 12_4.

[0023] Each sensor device 12 comprises a wired interface 16 for connection to the data transmission network 14 and a wireless interface 18 for data transmission by wireless signals FS. In this embodiment, the wireless interface 18 is a 5G mobile wireless interface, which means that it is configured to transmit and receive mobile wireless signals in accordance with the 5G standard.

[0024] In this embodiment, each sensor device 12 further comprises a three-axis gyroscope sensor unit 20 configured to detect rotation rates along three spatial axes and provide corresponding gyroscope sensor unit measurement data, and a three-axis acceleration sensor unit 22 configured to detect accelerations along the three spatial axes and provide corresponding acceleration sensor unit measurement data.

[0025] Each sensor device 12 further comprises a calculation unit 24. The calculation unit 24 is connected to the gyroscope sensor unit 20 and the acceleration sensor unit 22 and configured to process the gyroscope sensor unit measurement data and the acceleration sensor unit measurement data. The calculation unit 24 comprises a distance determination unit 26 configured to analyze the radio signal FS received from the antenna device 7 and to determine an antenna distance AA from each sensor device 12 to the antenna device 7 based on the radio signal FS.

[0026] In this embodiment, the sensor system 10 further comprises a central data processing device 28 arranged on the upper rotating body 3. The central data processing device 28 is connected to all the sensor devices 12 via the data transmission network 14 and has access to the gyroscope sensor unit measurement data of the gyroscope sensor unit 20, the acceleration sensor unit measurement data of the acceleration sensor unit 22, and the antenna distances AA of the individual sensor devices 12 determined by the distance determination unit 26.

[0027] The central data processing device 28 comprises a position determination unit 30. The position determination unit 30 is configured to determine individual position data for each sensor device 12 based on the measurement data and the antenna distances AA provided by the sensor devices 12. The respective position data indicate the spatial positions of the sensor devices relative to one another. The position determination unit 30 is further configured to provide the position data to each sensor device 12.

[0028] In this embodiment, the individual position data includes the sensor device distance SA from each sensor device 12 to each other sensor device 12. The sensor device distance SA between any two sensor devices 12 can be easily determined using a geometric relationship from the antenna distances AA of the two sensor devices 12 and the measurement data of the two sensor devices. For example, the sensor device distance SA_12 shown in FIG. 2 can be determined by the following equation:

[0029]

number

[0030] Here, the angles α_12 and β_12 can be derived from the measurement data of the first sensor device 12_1 and the measurement data of the second sensor device 12_2. Similarly, all other sensor device distances SA between two sensor devices 12 can be determined based on the antenna distances AA of the respective sensor devices 12 and the angles α and β, which can be derived from the measurement data of the respective sensor devices 12.

[0031] The position data preferably also includes, for each sensor device 12, relative 3D coordinates, meaning coordinates relative to a machine reference system, and / or absolute 3D coordinates, meaning coordinates relative to an Earth reference system.

[0032] The central data processing device 28 further comprises a sensor device calibration unit 32. The sensor device calibration unit 32 is configured to perform calibration 20 of the gyroscope sensor unit and / or calibration of the acceleration sensor unit 22 of one or more of the sensor devices 12 based on the antenna distances AA of the sensor devices 12. When the sensor device distance SA between two sensor devices 12 is known and, for example, a defined excavator state is set, the angles α_12 and β_12 shown in Fig. 2 can be determined, for example, from the antenna distances AA_1, AA_2 and the sensor device distance SA_12 by the following equations:

[0033]

number

[0034]

number

[0035] Based on the determined angles α_12 and β_12, the gyroscope sensor units 20 and / or acceleration sensor units 22 of the first sensor device 12_1 and the second sensor device 12_2 can be calibrated, respectively, so that the angles α_12 and β_12 that can be derived from the measurement data of the two sensor devices 12 match the angles α_12 and β_12 determined based on the antenna distance AA and the sensor device distance SA. Similarly, the gyroscope sensor units 20 and / or acceleration sensor units 22 of all other sensor devices 12 can also be calibrated based on their respective antenna distances AA and their respective sensor device distances SA.

[0036] The central data processing device 28 further includes a centrifugal force compensation unit 34. The centrifugal force compensation unit 34 is configured to determine a rotation axis distance DA from the rotation axis D for each of the sensor devices 12 based on the position data determined by the position determination unit 30. In this embodiment, since the first sensor device 12_1 is arranged directly on the rotation axis D, the rotation axis distance DA_1 of the first sensor device 12_1 is zero, and the rotation axis distances DA_2 to DA_4 of the remaining sensor devices 12_2 to 12_4 are each substantially equal to the sensor device distance SA between the respective sensor device 12 and the first sensor device 12_1. The centrifugal force compensation unit 34 is further configured to determine a centrifugal force acting on each of the sensor devices 12 when rotating about the rotation axis D based on the determined rotation axis distance DA and the measurement data of the individual sensor devices 12. Then, the centrifugal force compensation unit 34 is configured to perform correction of the gyroscope sensor unit measurement data and / or acceleration sensor unit measurement data of the individual sensor devices 12 based on the determined centrifugal force.

[0037] It is expressly noted that the functions of the central data processing device 28 provided in this embodiment can be performed in whole or in part by the computing units 24 of one or more sensor devices 12. In particular, the positioning unit 30, the sensor device calibration unit 32, and / or the centrifugal force compensation unit 34 can be included in the computing unit 24 of one of the sensor devices 12. Furthermore, it is also conceivable that there are several distributed positioning units, sensor device calibration units, and / or centrifugal force compensation units, which perform corresponding functions only for some of the sensor devices 12. For example, each sensor device 12 may have a separate positioning unit, sensor device calibration unit, and / or centrifugal force compensation unit, which perform corresponding functions only for the respective sensor device 12 itself.

[0038] Furthermore, it is explicitly pointed out that the sensor system according to the invention can be used universally for monitoring any kind of machine, in particular it can also be used for monitoring other construction machines, for example for monitoring cranes or bulldozers. [Explanation of symbols]

[0039] 1. Excavator 2 Undercarriage 3 Upper rotating body 4. Boom 5 Arm 6 buckets 7 Antenna equipment 10 Sensor System 12 Sensor device 14 Data Transmission Network 16 Wired Interfaces 18 Wireless Interface 20 Gyroscope Sensor Unit 22 Acceleration sensor unit 24 computing units 26 Distance Determination Unit 28 Central Data Processing Unit 30 Positioning Unit 32 Sensor device calibration unit 34 Centrifugal Force Compensation Unit AA Antenna Distance D rotation axis DA Rotation axis distance FS radio signal SA Sensor Device Distance

Claims

1. A sensor system (10) for monitoring a machine (1), said sensor system (10) comprising a plurality of sensor devices (12) and a position determination unit (30); Each of the plurality of sensor devices (12) a gyroscope sensor unit (20) and / or an acceleration sensor unit (22); a radio interface (18) for data transmission by radio signals; a distance determination unit (26) configured to analyze the received radio signal (FS) and to determine, based on said radio signal (FS), an antenna distance (AA) to the antenna arrangement (7) from which said received radio signal (FS) was transmitted, the positioning unit (30) is configured to be provided with measurement data from the gyroscope sensor unit (20) and / or measurement data from the acceleration sensor unit (22) and the antenna distances (AA) of at least two sensor devices (12) of the plurality of sensor devices (12); The position determination unit (30) is configured to determine position data for the at least two sensor devices (12) based on the provided measurement data and the antenna distance (AA), the position data indicating the relative spatial positions of the at least two sensor devices (12) to each other, in the sensor system (10).

2. 2. The sensor system (10) of claim 1, further comprising a sensor device calibration unit (32), wherein the sensor device calibration unit (32) is configured to perform calibration of the gyroscope sensor unit (20) and / or the acceleration sensor unit (22) of at least one sensor device (12) based on the antenna distances (AA) of the at least two sensor devices (12).

3. The centrifugal force compensation unit (34) further comprises: determining a rotation axis distance (DA) to a rotation axis (D) of the machine (1) to be monitored based on position data of at least one of the sensor devices (12); estimating a centrifugal force acting on each of the plurality of sensor devices (12) based on the determined rotation axis distance (DA) and the measurement data of the gyroscope sensor unit (20) and / or the measurement data of the acceleration sensor unit (22) of each of the plurality of sensor devices (12); 3. The sensor system (10) of claim 1, configured to perform correction of the measurement data of the gyroscope sensor unit (20) and / or the measurement data of the acceleration sensor unit (22) of each of the plurality of sensor devices (12) based on the estimated centrifugal force.

4. The sensor system (10) of claim 1, wherein the wireless interface (18) is a 5G mobile wireless interface. That's all.

Images