Encoder and system with such an encoder

Abstract

Encoder (10) for monitoring translational and / or rotational movements of a moving component (50), wherein the encoder (10) comprises: a sensor device (1) which is designed to determine motion information about the monitored component (50); an output unit (3) which is configured to communicate with a higher-level control unit (20); and an evaluation unit (5) which is designed to generate jerk information from the determined motion information, indicating a jerk of the monitored component (50), wherein the evaluation unit (5) is further designed to: to pass the generated jerk information together with at least some of the determined motion information to the output unit (3); and / or to make corrections to the determined motion information based on the generated jerk information and to pass at least part of the corrected motion information to the output unit (3); wherein the output unit (3) is designed to: to output the generated jerk information together with some of the determined motion information to the higher-level control unit (20); and / or to output part of the corrected motion information to the higher-level control unit (20).

Description

[0001] The present invention relates to an encoder for monitoring translational and / or rotational movement of a movable component, and to a system with such an encoder.

[0002] In a wide variety of systems, it is necessary to monitor the movement of a moving component and transmit the corresponding information to a higher-level control unit. This higher-level control unit then controls appropriate components, such as actuators, depending on the specific movement. The motion information gathered typically includes position and velocity data, and possibly acceleration data as well. This motion information is usually generated from motion signals transmitted by a sensor or encoder to the higher-level system. However, due to relatively large distances, for example, the connection between the encoder and the higher-level control unit often results in a significant limitation of the data transmission rate.In other words, the connection between the encoder and the higher-level control unit is only capable of transmitting a portion, specifically a fraction, of the information acquired by the encoder. For example, values ​​averaged over certain periods for the respective motion information are transmitted. This is generally not a problem, as the usual transmission rates are sufficient for adequate control of the relevant components.

[0003] However, there are applications where very short jerk events, in the form of a jolt (specifically a peak in the change in acceleration) of the moving component, are particularly problematic. These jerk events can lead to faulty motion information or even trigger a warning or error message, requiring the user to react accordingly. Consequently, in certain systems, it is necessary to reliably identify such jerk events and take them into account for the operation of the higher-level control unit.

[0004] Previously, such jerk events were always identified by analyzing motion information in the higher-level control unit. However, it has become apparent that such systems are not reliably capable of identifying particularly short jerk events in all applications.

[0005] The purpose of the invention is therefore to further develop known systems for better jerk detection.

[0006] To solve this problem, an encoder according to claim 1 and a system with such an encoder are proposed according to the invention.

[0007] The present invention relates to an encoder for monitoring translational and / or rotational movements of a moving component. An encoder according to the invention comprises: a sensor device configured to detect motion information about the monitored component; an output unit configured to communicate with a higher-level control unit; and an evaluation unit configured to generate jerk information from the detected motion information, indicating a jerk of the monitored component. The evaluation unit is further configured to transmit the generated jerk information, together with at least a portion of the detected motion information, to the output unit. Alternatively, orIn addition, the evaluation unit can also be configured to make corrections to the determined motion information based on the generated jerk information and to transfer at least a portion of the corrected motion information to the output unit. The output unit is configured to output the generated jerk information, along with a portion of the determined motion information or a portion of the corrected motion information, to the higher-level control unit.

[0008] Each of the individual components, such as the output unit, the evaluation unit, and / or the higher-level control unit, can include at least one dedicated processing unit, for example, in the form of an application-specific integrated circuit (ASIC), an FPGA (Field Programmable Gate Array), and / or a programmable microcontroller. The evaluation unit in the encoder makes it possible to use all the motion information provided by the sensor to determine jerk information. This allows even the shortest jerk events to be reliably detected and the subsequent control by the higher-level control unit to be adjusted accordingly. In particular, jerk events can also be detected that would otherwise be too slow to be resolved by the higher-level control unit due to the necessary reduction in the transmission rate required for data transfer.By transmitting relevant jerk information to the higher-level control unit, it can then react appropriately to the detected jerk event. Alternatively, the control system can be indirectly adjusted by directly correcting the determined motion information via the evaluation unit. This can, for example, save computing power at the higher-level control unit or allow the use of a simpler control unit without jerk correction, as this is performed directly in the encoder.

[0009] Preferably, the respective motion information includes position, velocity and / or acceleration information for the monitored component.

[0010] Such information can be obtained in a relatively simple and reliable way and is particularly well suited for jerk analysis.

[0011] Preferably, the evaluation unit is configured to generate jerk information such that it displays at least one value for the change in acceleration of the moving component. In particular, the evaluation unit is configured to determine said value for the change in acceleration of the moving component using the third derivative of the time course of determined position information, the second derivative of the time course of determined velocity information, and / or the first derivative of the time course of determined acceleration information. In short, the jerk information can include the first derivative of the acceleration information.

[0012] Determining jerk information in this way is relatively simple and reliable. Combining these methods allows for particularly reliable and detailed results.

[0013] Preferably, the output unit is configured to transmit information only at a rate lower than the rate at which the evaluation unit can provide the corresponding information. In other words, the evaluation unit can determine jerk information more frequently than the output unit transmits information to the higher-level control unit. To enable such frequent determination of jerk information, the evaluation unit can, for example, be configured to communicate directly with the sensor device and evaluate (high-frequency sampled) raw data from the sensor device to determine the jerk information. For example, in this way, the evaluation unit can receive position, velocity, and / or acceleration information from the sensor device so frequently that no jerk events go undetected.

[0014] This allows for a simple and inexpensive output to be used in the encoder and / or the higher-level control unit to be positioned particularly far away from the encoder, thus making it particularly flexible and user-friendly.

[0015] This results in advantages over the current state of the art. For example, monitoring of mechanical components (so-called condition monitoring) is possible even during operation. For multi-turn encoders, it is possible, for instance, to monitor wear effects in the gear stages and issue warning or error signals in the event of changes. Mechanical changes outside the encoder (e.g., of a bearing in the motor) can also be monitored. Furthermore, position, speed, and / or acceleration accuracy can be increased.

[0016] The evaluation unit can be an integrated circuit (IC), for example a DSP (Digital Signal Processor), an FPGA (Field Programmable Gate Array), or an ASIC (Application Specific Integrated Circuit). The evaluation unit and the sensor device can be located, for example, within the encoder, preferably within the same housing.

[0017] Preferably, the sensor device comprises at least one, and in particular several, sensors, especially in the form of linear sensors and / or angle sensors, which detect the movement of a measuring instrument, for example via magnetic sensors, brightness sensors and / or photodiodes.

[0018] Multiple sensors enable particularly precise and reliable monitoring of the movement of the moving component. The sensors mentioned as examples are particularly reliable types of suitable sensors.

[0019] Preferably, the evaluation unit is designed such that the correction of the determined motion information only leads to an adjustment of the values ​​from the motion information if at least one value displayed by the jerk information reaches or exceeds a preset or variable threshold and is still below a preset or variable limit value.

[0020] The threshold allows for the avoidance of minor corrections to the motion information to save computing resources. The limit defines a range beyond which corrections to the motion information are no longer sufficient to ensure reliable system control. The term "variable" encompasses both user-adjustable values ​​and values ​​that can change depending on other values.

[0021] Preferably, the evaluation unit is designed to provide the generated jerk information with a warning or error message, or to output jerk information in the form of such a warning or error message, if the value displayed by the jerk information exceeds or has exceeded the preset or variable limit.

[0022] Such a warning or error message is to be understood as a separate indication of the aforementioned exceedance and therefore does not require a separate analysis by the higher-level control unit to determine such an exceedance. The respective limit value is, in particular, encoder-specific, i.e., dependent on the individual encoder and stored or storable within it. This facilitates the integration of an encoder according to the invention into a system with a corresponding higher-level control unit.

[0023] Preferably, the evaluation unit is configured to generate the jerk information from digitized motion information from the sensor device. The digitized motion information can, in particular, be generated with a sampling rate that is at least 10 times, preferably 100 times, higher than the rate or frequency with which the output unit communicates information to the control unit.

[0024] Specifically, the sensor device is also designed to digitize the measurement signals from its sensors and transmit them to the evaluation unit as digitized signals that can be easily processed further.

[0025] The evaluation unit can also be designed to generate jerk information from analog motion information from the sensor device and, in particular, to digitize the corresponding information before it is transmitted to the higher-level control unit.

[0026] This allows for the use of particularly simple sensor devices and simplified processing of the digitized information. In particular, this digitization also enables the wireless transmission of the respective information to the higher-level control unit.

[0027] Preferably, the encoder further comprises a memory and / or a register. The evaluation unit is configured to store generated jerk information, in particular together with an associated timestamp, in the memory or to write it to the register.

[0028] This allows the generated jerk information to be saved in the encoder itself, and thus enables subsequent evaluation of this information, regardless of whether the jerk information was transmitted to the higher-level control unit or not.

[0029] A system according to the invention comprises a movable component, a higher-level control unit, and a previously described encoder. The encoder is designed to monitor the movement of the movable component and is coupled to the higher-level control unit for transmitting determined motion information, jerk information, and / or corrected motion information.

[0030] The integration of an encoder according to the invention into a corresponding system enables particularly reliable and suitable control of the system components, especially in the case of particularly sensitive systems.

[0031] Preferably, the system also includes an actuator for the targeted movement of the component. The higher-level control unit is designed to control the operation of the actuator based on the information received from the encoder.

[0032] Such an actuator represents a simple and reliable way to utilize the information transmitted to the higher-level control unit.

[0033] Preferably, the higher-level control unit is designed to correct motion information received from the encoder based on jerk information received from the encoder.

[0034] Specifically, the higher-level control unit is thus able to make necessary adjustments to the motion information based on the jerk information and to generate corrected motion information itself. The higher-level control unit does not need to attempt to generate suitable jerk information itself from the reduced set of motion information it receives.

[0035] Preferably, the system further comprises a user interface and is designed to output a warning or error signal via the user interface, in particular visually and / or audibly, when the jerk information received from the encoder indicates that a value displayed by the jerk information exceeds a preset or variable limit, or when a corresponding warning or error message is received from the encoder.

[0036] Such a user interface facilitates operation by a user and, in particular, the error analysis of the system.

[0037] Further details will follow from the description of the figures below. The figures show: Fig. 1 a schematic structural extension of an exemplary system according to the present invention; and Fig. 2. A process diagram to illustrate the functionality of the in Fig. 1 of the encoders shown.

[0038] As in Fig. As shown in Figure 1, a system 100 according to the invention comprises, for example, a movable component 50, a higher-level control unit 20 and an encoder 10. The encoder 10 is communicatively coupled with the higher-level control unit 20.

[0039] The encoder 10 is configured to monitor translational and / or rotational movements of the movable component 50. For this purpose, the encoder 10 comprises a sensor device 1 and an evaluation unit 5. The sensor device 1 includes at least one sensor 7 and, in the illustrated embodiment, a data acquisition and processing unit 9, which is configured to receive signals from the sensors 7 and to process them in preparation for further evaluation.

[0040] In the illustrated embodiment, the sensors 7 are brightness sensors, e.g. photodiodes, which are directed onto a measuring track illuminated by light sources (see Fig. 1) are aligned with the moving component 50. The data collection and processing unit 9 is designed to receive analog brightness signals from the sensors 7 and convert them into motion information, in particular in the form of position or speed information, for the moving component 50 and forward them to the evaluation unit 5 of the encoder.

[0041] The evaluation unit 5 is designed to analyze the received motion information and generate so-called jerk information, i.e., information about jerky movements of component 50. Specifically, the evaluation unit 5 does this by performing a triple derivative of the time course of position information, a double derivative of the time course of velocity information, and / or a single derivative of the time course of acceleration information from the received motion information. A peak in the curve of the respective derivative directly indicates a jerk in the movement of the moving component 50.

[0042] The evaluation unit 5 is configured to store or enter the generated jerk information in a designated memory or register 12. This is preferably done together with a corresponding timestamp. Furthermore, the evaluation unit 5 can either use the generated jerk information to correct the determined motion information and transfer at least part of the corrected motion information to a corresponding output unit 3 for transmission to the higher-level control unit 20, or transfer the generated jerk information together with the determined motion information to a corresponding output unit 3 for transmission to the higher-level control unit 20.

[0043] Output unit 3 is coupled to the higher-level control unit 20 for communication and transmits the information received from evaluation unit 5 to the higher-level control unit 20 in a suitable manner. Only a portion of the information generated by sensor unit 1 is transmitted to the higher-level control unit 20 in compressed or abstracted form. This compression or abstraction is necessary to achieve real-time transmission of the information and is therefore required by the available transmission rate between output unit 3 and the higher-level control unit 20.

[0044] In this case, evaluation unit 5 is designed such that the correction of the determined motion information only leads to an adjustment of the values ​​from the motion information if at least one value displayed by the jerk information reaches or exceeds a preset or variable threshold and is still below a preset or variable limit value. In other words, a correction of the determined motion information only takes place within a specific range.

[0045] This leads to the following three situations: A) The jerk information is used by evaluation unit 5 to correct the determined motion information; however, because the threshold is not exceeded, the corrections do not change the motion information. This is effectively equivalent to foregoing the correction of the motion information when the threshold is not exceeded. B) The jerk information is used by the evaluation unit 5 to correct the determined motion information, whereby the corrections due to reaching or exceeding the threshold result in actual changes to the motion information. C) The jerk information is not used by evaluation unit 5 to correct the determined motion information because the limit value is exceeded. In this case, evaluation unit 5 adds a warning or error message to the generated jerk information or outputs the jerk information in the form of such a warning or error message.

[0046] Data transmission from the data collection and processing unit 9 to the evaluation unit 5 can be either analog or digital, although the transmission of information to the higher-level control unit 20 is preferably always digital. This enables more flexible and efficient transmission and further processing of the respective information.

[0047] For clarity, a flowchart illustrating the basic functionality of the encoder 10 shown is included in Fig. 2 is shown, but will not be described in detail again below to avoid unnecessary repetition.

[0048] Returning to Fig. In the exemplary system 100, an actuator 30 is also included for the targeted movement of the component 50. The higher-level control unit 20 is designed to control the operation of the actuator 30 depending on the information received from the encoder 10.

[0049] If the higher-level control unit 20 receives motion information and jerk information from the encoder 10, it can either correct the motion information itself or adjust its behavior in other ways depending on the jerk information received.

[0050] Finally, the system 100 can also include a user interface 40, through which, for example, a warning or error signal can be output visually and / or audibly when jerk information received from the encoder 10 indicates that a value displayed by the jerk information exceeds a preset or variable limit, or when a corresponding warning or error message is received from the encoder 10.

[0051] Finally, it should be noted that the illustrated embodiment is merely one of many possible ways to implement the claimed design. The described embodiment is not intended to directly limit the scope of protection. This is defined solely by the independent patent claims. Reference symbol list 1 sensor device 3 Output unit 5 evaluation units 7 Sensor 9 Data collection and processing unit 10 encoders 12 Memory locations or registers 20 higher-level control unit 30 actuator 40 User interface 50 moving component 100 System

Claims

[1] Encoder (10) for monitoring translational and / or rotational movements of a movable component (50), the encoder (10) comprising: a sensor device (1) which is designed to determine movement information about the monitored component (50); an output unit (3) which is designed to communicate with a higher-level control unit (20); and an evaluation unit (5) which is designed to generate jerk information indicating a jerk of the monitored component (50) from the determined movement information, wherein the evaluation unit (5) is further designed to: to transfer the generated jerk information together with at least part of the determined movement information to the output unit (3); and / or to make corrections to the determined movement information based on the jerk information generated and to transfer at least part of the corrected movement information to the output unit (3); wherein the output unit (3) is designed to: output the jerk information generated together with a portion of the determined movement information to the higher-level control unit (20); and / or to output part of the corrected movement information to the higher-level control unit (20). [2] Encoder (10) according to claim 1, wherein the movement information comprises position, speed and / or acceleration information about the monitored component (50). [3] Encoder (10) according to claim 2, wherein the evaluation unit (5) is designed to generate the jerk information in such a way that it indicates at least one value for the acceleration change of the movable component (50), wherein the evaluation unit (5) is designed in particular to determine said value for the change in acceleration of the movable component (50) with the aid of the third derivative of the temporal course of determined position information, the second derivative of the temporal course of determined speed information and / or the first derivative of the temporal course of determined acceleration information. [4] Encoder (10) according to one of the preceding claims, wherein the output unit (3) is designed only to transmit information at a rate which is lower than the rate at which the evaluation unit (5) can provide the corresponding information. [5] Encoder (10) according to one of the preceding claims, wherein the sensor device (1) comprises at least one, in particular several sensors (7), in particular in the form of linear sensors and / or angle sensors, which detect the movement of a measuring embodiment in particular via magnetic sensors, brightness sensors and / or photodiodes. [6] Encoder (10) according to one of the preceding claims, wherein the evaluation unit (5) is designed such that the correction of the determined movement information only leads to an adjustment of the values ​​from the movement information if at least one value indicated by the jerk information reaches or exceeds a preset or variable threshold value and is still below a preset or variable limit value. [7] Encoder (10) according to claim 6, wherein the evaluation unit (5) is designed to provide the generated jerk information with a warning or error message or to output jerk information in the form of such a warning or error message if the value indicated by the jerk information exceeds or has exceeded the preset or variable limit value. [8] Encoder (10) according to one of the preceding claims, wherein the evaluation unit (5) is designed to generate the jerk information from digitized movement information from the sensor device (1). [9] Encoder (10) according to one of claims 1 to 7, wherein the evaluation unit (5) is designed to generate the jerk information from analogue movement information from the sensor device (1) and in particular to digitise the corresponding information before it is transmitted to the higher-level control unit (20). [10] Encoder (10) according to one of the preceding claims, further comprising a memory (12) and / or a register (12), wherein the evaluation unit (5) is designed to store generated jerk information, in particular together with an associated time stamp, in the memory (12) or to write it into the register (12). [11] System (100) with a movable component (50), a higher-level control unit (20) and an encoder (10) according to one of the preceding claims, wherein the encoder (10) is designed to monitor the movement of the movable component (50) and is coupled to the higher-level control unit (20) for transmitting determined movement information and jerk information or corrected movement information. [12] System (100) according to claim 11, wherein the system (100) further comprises an actuator (30) for the targeted movement of the component (50) and the higher-level control unit (20) is designed to control the operation of the actuator (30) depending on the information received from the encoder (10). [13] System (100) according to claim 11 or 12, wherein the higher-level control unit (20) is designed to correct movement information received from the encoder (10) based on jerk information received from the encoder (10). [14] System (100) according to one of claims 11 to 13, wherein the system (100) further comprises a user interface (40) and is designed to output a warning or error signal via the user interface (40), in particular visually and / or acoustically, if the jerk information received from the encoder (10) indicates that a value displayed thereby exceeds a preset or variable limit value, or if a corresponding warning or error message is received from the encoder (10).

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