DE202022103366U1 - Device for monitoring the functionality of a device for determining position, length or angle - Google Patents

Abstract

Device (10) for monitoring a functionality of a device for determining position, length or angle, the device (10) comprising:
- a transmission area (100), comprising at least one transmission element (110);
- a reception area (200), comprising at least one reception element (210);
- a coding area (300) which forms a code word (310) with a predefined, finite length from a plurality of successive elements (311-320) which represent a logical one or a logical zero;
- wherein the transmission area (100), the reception area (200) and the coding area (300) are arranged and designed to be movable relative to one another in such a way that the receiving element (210) depends on the position of the coding area (300) and/or the transmission area (100 ) receives a logical one or a logical zero to the reception area (200); and
- an evaluation unit (400) which is designed to detect all transitions from a logical one to a logical zero and all transitions from a logical zero to a logical one of the code word (310) and compare them with a reference value of the code word.

Description

The invention relates to a device for monitoring the functionality of a device for determining position, length or angle.

Devices for determining position, length or angle, also known as encoders or coders, are devices that can record and output signals from mechanical movements.

There are both devices that are designed to be rotational, i.e. detect a rotational movement, and devices that are designed to be linear, i.e. detect a longitudinal movement. These devices can, for example, work optically, magnetically, capacitively or inductively and thus record a position, a length or an angle.

For example, external influences can cause the detection to be falsified, as a result of which the detection of a position, a length or an angle is falsified. In order to detect this falsification, a device is used to monitor the functionality of a device for determining position, length or angle.

From the publication EP 2 647 967 B1 For example, a system and method for monitoring output signals of an encoder is known.

It is an object of the present invention to provide an improved device and an improved method for monitoring the functionality of a device for determining position, length or angle.

This object is achieved by a device for monitoring the functionality of a device for determining position, length or angle according to independent claim 1.

This device according to the invention initially comprises a transmission area with at least one transmission element. The transmitting element is designed to send out a signal. The transmitting element can be optical, magnetic, capacitive or inductive and can emit a corresponding signal. In the case of an optical transmitting element, it can be, for example, a semiconductor light source, in particular an LED. The transmission area can in particular have more than one transmission element, for example two, four, eight or more transmission elements.

The device further comprises a reception area with at least one reception element. The receiving element is designed to receive the signal emitted by the transmitting element. The receiving element can also be designed optically, magnetically, capacitively or inductively and can receive a corresponding signal. In particular, the receiving element is designed to correspond to the transmitting element. In the case of an optical receiving element, it can be, for example, a semiconductor light receiver, in particular a photodiode. The reception area can also have several reception elements, in particular the same number as there are transmission elements.

The device also includes a coding area that forms a code word. The code word consists of a predefined finite length of several consecutive elements that represent a logical one or a logical zero. The coding area can also be optical, magnetic, capacitive or inductive. In particular, the coding area is designed to correspond to the transmitting element and the receiving element. In the case of an optical coding element, an element representing a logical one is a portion that is transparent to light, and an element representing a logical zero is a portion that is opaque, or vice versa, that is, an element that is a logical zero represents a section that is translucent and an element that represents a logical one is a section that is opaque.

For example, the code word includes at least one and one zero. In particular, the code word comprises more than two elements, in particular four, eight, nine, ten, twelve or 16 elements, which consist of consecutive ones and zeros.

In particular, the code word is an absolute code word.

The transmission area, the reception area and the coding area are arranged and designed to be movable relative to one another in such a way that the receiving element receives a logical one or a logical zero depending on the position of the coding area and/or the transmission area in relation to the reception area.

The device also includes an evaluation unit which is designed to detect all transitions from a logical one to a logical zero and all transitions from a logical zero to a logical one of the code word and compare them with a reference value of the code word.

For this purpose, the evaluation unit includes an application-specific integrated circuit (ASIC), a field-programmable gate arrangement (FPGA) and/or a microcontroller.

The solution according to the invention makes it possible to permanently or continuously monitor the function of the device for determining position, length or angle during operation. In particular, the solution according to the invention, in contrast to the prior art, compares the entire code word, which makes it possible to determine both global and local distortions in the detection of the position, length or angle.

The device can be further developed in that the evaluation unit is designed to detect a time of the transitions from a logical one to a logical zero and the transitions from a logical zero to a logical one and compare them with a reference value of the times.

In particular, the evaluation unit is designed to record the temporal and/or spatial distance between the transition from a logical zero to a logical one and vice versa. This distance between edges of the signal can also be referred to as the duty cycle or duty cycle and corresponds to the position of the switching threshold for each individual receiving element.

This further development enables a particularly precise comparison.

The device can be further developed in that the evaluation unit is also designed to detect a deviation, in particular a standard deviation and/or an expected value of the transitions from a logical one to a logical zero and the transitions from a logical zero to a logical one to a respective reference value capture.

This makes it particularly easy to detect global falsifications.

The device can be further developed in that the evaluation unit is also designed to determine a correction value based on the comparison.

This correction value can in particular be a correction value that is provided to the device for position, length or angle determination in order to use it during the detection and thus correct any falsification.

This can be done in particular by adapting the transmission element based on the correction value. Alternatively or additionally, the receiving element can also be adapted. For example, the transmitting element and/or the receiving element can be readjusted.

The device can be further developed in that the evaluation unit is further designed to output an error based on the comparison.

The error can be output both on the device according to the invention and on the device for determining position, length or angle.

In particular, the evaluation unit can be designed to detect and output a degree of error, for example a degree of falsification.

In addition, the evaluation unit can also be designed to detect a deterioration in the adulteration and, in particular, to output this deterioration.

Likewise, the evaluation unit can also be designed to output a determined expected value and/or a determined standard deviation.

In particular, the evaluation unit can be designed to issue a maintenance and/or replacement recommendation of a component of the device for position, length or angle determination, further in particular based on the degree of falsification and/or deterioration.

The task mentioned at the beginning is also solved by a method for monitoring the functionality of a device for determining position, length or angle. The method includes providing a device for monitoring a functionality of a device for position, length or angle determination, in particular a device according to one of the previously described embodiments, detecting all transitions from a logical one to a logical zero and all transitions from one logical zero to a logical one of a code word; and comparing the captured transitions with a reference value of the code word.

The method can be further developed in that it additionally includes determining a correction value based on the comparison.

The method can be further developed in that it additionally includes adjusting the transmitting element and/or the receiving element based on the correction value.

The method can be further developed in that it additionally includes outputting an error based on the comparison.

With regard to the advantages and embodiments of the method, reference is made to the advantages and embodiments of the device described above.

• 1 eine schematische Ansicht einer Vorrichtung zur Überwachung einer Funktionalität eines Geräts zur Positions-, Längen- oder Winkelbestimmung;
• 2 ein Ablaufdiagramm eines Verfahrens zur Überwachung einer Funktionalität eines Geräts zur Positions-, Längen- oder Winkelbestimmung;
• 3 eine beispielhafte Auswertung die durch eine Vorrichtung zur Überwachung einer Funktionalität eines Geräts zur Positions-, Längen- oder Winkelbestimmung, wie in 1 gezeigt, und/oder ein Verfahren zur Überwachung einer Funktionalität eines Geräts zur Positions-, Längen- oder Winkelbestimmung, wie in 2 gezeigt, erfolgt; und
• 4 eine weitere beispielhafte Auswertung die durch eine Vorrichtung zur Überwachung einer Funktionalität eines Geräts zur Positions-, Längen- oder Winkelbestimmung, wie in 1 gezeigt, und/oder ein Verfahren zur Überwachung einer Funktionalität eines Geräts zur Positions-, Längen- oder Winkelbestimmung, wie in 2 gezeigt, erfolgt.

Embodiments of a device and a method for monitoring the functionality of a device for position, length or angle determination will now be described in more detail in connection with the following figures. Show it:

• 1 a schematic view of a device for monitoring a functionality of a device for determining position, length or angle;
• 2 a flowchart of a method for monitoring a functionality of a device for determining position, length or angle;
• 3 an exemplary evaluation carried out by a device for monitoring the functionality of a device for position, length or angle determination, as in 1 shown, and/or a method for monitoring a functionality of a device for position, length or angle determination, as in 2 shown, done; and
• 4 a further exemplary evaluation carried out by a device for monitoring the functionality of a device for position, length or angle determination, as in 1 shown, and/or a method for monitoring a functionality of a device for position, length or angle determination, as in 2 shown, takes place.

The same reference numbers designate the same or similar features.

1 shows a schematic view of a device 10 for monitoring the functionality of a device for determining position, length or angle.

The device 10 includes a transmission area 100 with a transmission element 110 and a reception area 200 with a reception element 210.

The device 10 also includes a coding area 300 which forms a code word 310 with a predefined, finite length from a plurality of successive elements 311, 312, 313, 314, 315, 316, 317, 318, 319 and 320, which are a logical one or a represent logical zero. By way of example, a code word 310 is formed with ten elements, the element 311 being a one, the element 312 being a zero, the element 313 being a zero, the element 314 being a one, the element 315 being a zero, the element 316 being a one, the element 317 represents a zero, the element 318 represents a zero, the element 319 represents a zero and the element 320 represents a one. The code word 310 corresponds to the number sequence 1 0 0 1 0 1 0 0 0 1.

By way of example, the transmitting element 110 is shown as an LED, the receiving element 210 as a photodiode and the code word made up of translucent and opaque areas. The elements 312, 313, 315, 317, 318 and 319, which represent a zero, are therefore opaque and the elements 311, 314, 316 and 320, which represent a one, are translucent.

The transmission area 100, the reception area 200 and the coding area 300 are arranged and designed to be movable relative to one another along a direction R in such a way that the receiving element 210 receives a logical one or a logical zero depending on the position of the coding area 300 relative to the reception area 200.

The device 10 also includes an evaluation unit 400, which is designed to detect all transitions from a logical one to a logical zero and all transitions from a logical zero to a logical one of the code word 310 and compare them with a reference value of the code word.

In particular, the evaluation unit 400 is designed to detect a point in time of the transitions from a logical one to a logical zero and the transitions from a logical zero to a logical one and to compare it with a reference value of the points in time.

The evaluation unit 400 is also designed to detect a deviation, in particular a standard deviation and/or an expected value of the transitions from a logical one to a logical zero and the transitions from a logical zero to a logical one to a respective reference value.

The evaluation unit 400 is further designed to determine a correction value based on the comparison or the detected deviation and adjust a function of the transmitting element 110 and/or the receiving element 210 based on this correction value.

Likewise, the evaluation unit 400 is further designed to output an error based on the comparison or the detected deviation.

The functions of the device 10 are now based on the in 1 Code word 310 shown is explained as an example. As stated before, the code word, which can also be referred to as the absolute word, is 1 0 0 1 0 1 0 0 0 1. It is now based on the distance of the edges, which can also be referred to as the duty cycle, between the elements One and zero recorded by the evaluation device. For the example shown, this is two elements for the distance 1 0 0 1, one element for the distance 0 1 0, one element for the distance 1 0 1, one element for the distance 0 1 0 and three elements for the distance 1 0 0 0 1.

In order for the distances to be comparable, they must first be standardized. For this purpose, the average value is formed for all periods between the edges, so that the standardized distance is the same for these areas. The standardized duty cycle is half of the standardized distance.

In the example shown here, it is assumed that the transparency of the code area or the elements of the code word has changed globally. For the aforementioned example, the receiving element 210 initially receives the following distance: 2.2, 0.9, 1.1, 0.9 and 3.3. The resulting standardized distance for the code word 310 between the total of ten elements is therefore 1.1, 1.1, 0.9, 1.1, 0.9, 1.1, 1.1, and 1.1. The standardized duty cycle is therefore 0.45 or 0.55, depending on whether the duty cycle is referenced to zero or one.

This absolute word can then be determined over the entire resolution of, for example, 1024 bits and recorded in a table.

This table can then be recorded over several times t1 to t2 and evaluated statistically. A continuous deterioration can then be derived from this, for example because the duty cycle increases over time.

Based on this, warnings and/or instructions can then be issued

2 shows a flowchart of a method 1000 for monitoring the functionality of a device for determining position, length or angle.

The method 1000 begins in a first step 1010, in which a device for monitoring a functionality of a device for position, length or angle determination, in particular a device as in 1 shown is provided.

In a subsequent step 1020, all transitions from a logical one to a logical zero and all transitions from a logical zero to a logical one of a code word are recorded.

In a subsequent step 1030, the detected transitions are compared with a reference value of the code word.

In a further step 1040, a correction value is determined based on the comparison.

In a further step 1050, the transmitting element and/or the receiving element is adjusted based on the correction value.

In a further step 1060, an error is issued based on the comparison.

3 shows an exemplary evaluation carried out by a device for monitoring the functionality of a device for position, length or angle determination, as in 1 shown, and/or a method for monitoring a functionality of a device for position, length or angle determination, as in 2 shown, takes place.

It can be seen that over time the transparency of the code area changes, in particular worsens. This changes both the expected value and the standard deviation of the comparison.

4 shows a further exemplary evaluation carried out by a device for monitoring the functionality of a device for determining position, length or angle, as in 1 shown, and/or a method for monitoring a functionality of a device for position, length or angle determination, as in 2 shown, takes place.

It can be seen that the vast majority of code elements function properly. The switching threshold for these is 0.5. However, a few code elements are affected by contamination, for example. The switching threshold for these is 0.8. Through clever evaluation, in particular Through clustering, these few code elements can be captured and ignored in global computation.

Reference symbol list

10

contraption

100

transmission range

110

Send element

200

Reception area

210

Receiving element

300

Code area

310

code word

311

Code element

312

Code element

313

Code element

314

Code element

315

Code element

316

Code element

317

Code element

318

Code element

319

Code element

320

Code element

400

Evaluation unit

1000

Proceedings

1010

Procedural step

1020

Procedural step

1030

Procedural step

1040

Procedural step

1050

Procedural step

1060

Procedural step

R

Direction

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 2647967 B1 [0005]

Claims (7)

Device (10) for monitoring a functionality of a device for determining position, length or angle, the device (10) comprising: - a transmission area (100), comprising at least one transmission element (110); - a reception area (200), comprising at least one reception element (210); - a coding area (300) which forms a code word (310) with a predefined, finite length from a plurality of successive elements (311-320) which represent a logical one or a logical zero; - wherein the transmission area (100), the reception area (200) and the coding area (300) are arranged and designed to be movable relative to one another in such a way that the receiving element (210) depends on the position of the coding area (300) and/or the transmission area (100 ) receives a logical one or a logical zero to the reception area (200); and - an evaluation unit (400) which is designed to detect all transitions from a logical one to a logical zero and all transitions from a logical zero to a logical one of the code word (310) and compare them with a reference value of the code word. Device (10) after Claim 1 , wherein the evaluation unit (400) is designed to detect a time of the transitions from a logical one to a logical zero and the transitions from a logical zero to a logical one and compare them with a reference value of the times. Device (10) according to one of the preceding claims, wherein the evaluation unit (400) is further designed to detect a deviation of the transitions from a logical one to a logical zero and the transitions from a logical zero to a logical one to a respective reference value. Device (10) after Claim 3 , wherein the evaluation unit (400) is further designed to record a standard deviation over the transitions from a logical one to a logical zero and the transitions from a logical zero to a logical one to a respective reference value. Device (10) according to one of the preceding claims, wherein the evaluation unit (400) is further designed to determine a correction value based on the comparison. Device (10) after Claim 5 , wherein the evaluation unit (400) is further designed to adapt the transmitting element (110) and/or the receiving element (210) based on the correction value. Device (10) according to one of the preceding claims, wherein the evaluation unit (400) is further designed to output an error based on the comparison.

Images