Detection system, detection method, and detection program

Abstract

To enable object detection to be performed using a simple system. [Solution] The detection system 1 includes a sensor 10 that measures the capacitance generated between itself and an object, and a processing device 2 that performs object detection processing based on the measured capacitance and a reference value which is a reference capacitance. The processing device 2 includes a determination unit 21 that determines whether the object is in a non-proximity state, a proximity state, or a contact state based on the measured value, the reference value, and approach and contact thresholds set in the sensor 10, a calibration unit 22 that performs calibration of the reference value when it is determined to be in a non-proximity state, and does not perform calibration when it is determined to be in a proximity state or a contact state, a correction unit 23 that creates and outputs a correction value when it is determined to be in a contact state, and a processing unit 24 that performs correction processing to correct the reference value or measured value by the correction value when the correction value is output.

Description

Technical Field

[0001] The present invention relates to a detection system and a detection method for detecting an object, and a detection program for causing a computer to execute the detection method.

Background Art

[0002] As a sensor system provided with a capacitance sensor, in paragraph

[0026] and FIG. 1 of Japanese Patent No. 7420374, the proximity of an object (100) is detected by measuring the capacitance generated between the object (100) and an electrode that is close to the object (100). Further, in this sensor system, it is described that a reference change process for changing a reference capacitance during the measurement of capacitance is executed (see claims 1, 6, 7, paragraphs

[0007] ,

[0011] ,

[0046] ,

[0048] , and FIG. 4 of the same publication).

Summary of the Invention

Problems to be Solved by the Invention

[0003] However, in the system described in the above publication, the above reference change process is always executed during the measurement of capacitance (that is, not only when the object is not approaching (including when stopped), but also when approaching and contacting the object (that is, after the approach state transition)). Therefore, very complicated control is required, and the system has become complicated.

[0004] The present invention has been made in view of such a conventional situation, and the problem to be solved by the present invention is to enable detection of non-approach, approach, and contact of an object with a simple system.

Means for Solving the Problems

[0005] The detection system according to the present invention is for detecting an object and comprises a sensor that measures the capacitance generated between itself and the object, and a processing unit that performs object detection processing based on the measured capacitance value measured by the sensor and a reference value which is a reference capacitance in the sensor. The processing unit comprises a determination unit that determines whether the object is in a non-approach state, an approach state, or a contact state based on the measured value, the reference value, and approach and contact threshold values ​​set in the sensor, a calibration unit that performs calibration of the reference value when the determination unit determines that the object is in a non-approach state, and does not perform calibration when the determination unit determines that the object is in an approach state or a contact state, a correction unit that creates and outputs a correction value when the determination unit determines that the object is in a contact state, and a processing unit that performs correction processing to correct the reference value or measured value by the correction value when the correction value is output from the correction unit.

[0006] In this invention, the capacitance generated between the object and the sensor is measured by a sensor, and the processing unit performs object detection processing based on the measured capacitance value and a reference value which is the reference capacitance in the sensor. During the detection processing, the determination unit determines whether the object is in a non-proximity state, a proximity state, or a contact state based on the measured value, the reference value, and the proximity and contact threshold values ​​set in the sensor. When the determination unit determines that the object is in a non-proximity state, the calibration unit performs calibration of the reference value. When the determination unit determines that the object is in a proximity state or a contact state, calibration is not performed by the calibration unit. When the determination unit determines that the object is in a contact state, the correction unit creates and outputs a correction value. When the correction unit outputs a correction value, the processing unit performs correction processing to correct the reference value or measured value by the correction value.

[0007] Thus, in this invention, calibration of the reference value by the calibration unit is performed when the determination unit determines that the object is not approaching, but not when the determination unit determines that the object is approaching or in contact. Furthermore, correction processing of the reference value by the processing unit is performed when the determination unit determines that the object is in contact. Therefore, calibration and correction processing are not performed continuously while capacitance is being measured. This makes it possible to detect non-approaching, approaching, and contacting states of an object with a simple system.

[0008] In this invention, when a correction value is output from the correction unit, each threshold value is corrected using that correction value.

[0009] In this invention, when a correction value is output from the correction unit, the correction value is reset stepwise when calibration is performed when transitioning to a non-proximity state.

[0010] In the present invention, the approach threshold has an approach ON threshold applied when the object transitions to an approach state and an approach OFF threshold applied when the object moves away from the approach state, and the contact threshold has a contact ON threshold applied when the object transitions to a contact state and a contact OFF threshold applied when the object moves away from the contact state.

[0011] In this invention, when a correction value is output from the correction unit, the correction value is added to each threshold value to correct each threshold value, and the difference between the approach ON threshold and the approach OFF threshold, and the difference between the contact ON threshold and the contact OFF threshold remain constant before and after the correction.

[0012] In this invention, when a non-proximity state is determined, calibration is performed using the average value of the measured values ​​over a certain period as the new reference value.

[0013] In this invention, the determination unit uses the difference between the measured value and the reference value as the determination value, and determines whether the object is in a non-proximity state, a proximity state, or a contact state by comparing the determination value with each threshold value.

[0014] In this invention, the sensor is for measuring the capacitance generated between a robot or moving body and an object.

[0015] The detection method according to the present invention is a method for detecting an object, and comprises the following steps. i) A process of measuring the capacitance generated between the object and the sensor. ii) A step of determining whether the object is in a non-proximity state, a proximity state, or a contact state, based on the measured capacitance value measured by the sensor, a reference value which is the reference capacitance in the sensor, and the proximity and contact thresholds set in the sensor. iii) A step of performing calibration of the reference value when it is determined that the state is not close, not performing calibration when it is determined that the state is close or in contact, and creating and outputting a correction value when it is determined that the state is in contact. iv) When a correction value is output, the process of correcting the reference value or measured value using the said correction value.

[0016] In this invention, when a correction value is output, the correction value is added to the threshold to correct the threshold.

[0017] In this invention, when a correction value is output, the correction value is reset stepwise during calibration when the system transitions to a non-proximity state.

[0018] The detection program according to the present invention is for causing a computer to execute the above-described detection method. [Effects of the Invention]

[0019] As described above, according to the present invention, there is an effect that detection of non-approach, approach, and contact with respect to an object can be realized with a simple system.

Brief Description of the Drawings

[0020] [Figure 1] It is a front view of a vertical articulated robot to which the detection system according to the present invention is applied. [Figure 2] It is a view taken in the direction of arrow II of FIG. 1. [Figure 3] It is a sectional view taken along line III-III of FIG. 2. [Figure 4] It is a schematic block configuration diagram of a detection system according to an embodiment of the present invention. [Figure 5] It is a flowchart for explaining the control flow by the detection system (FIG. 4). [Figure 6] It is an operation graph showing an example of a measurement value by a capacitance sensor constituting the detection system (FIG. 4) and an example of a method of calibration and correction for this.

Modes for Carrying Out the Invention

[0021] Hereinafter, embodiments of the present invention will be described based on the accompanying drawings. FIGS. 1 to 6 are diagrams for explaining a detection system and a detection method according to an embodiment of the present invention.

[0022] FIG. 1 shows a robot to which the detection system according to this embodiment is applied. Here, a vertical articulated robot is taken as an example. The robot 100 has three arms 101, 102, 103 and an end effector 104, and each of the arms 101, 102, 103 and the end effector 104 is driven and controlled by a drive control signal from a controller 110.

[0023] Arm 101 is equipped with a non-contact sensor 10 that detects objects (such as people or objects) without contact. A capacitive sensor is used as the non-contact sensor 10. The capacitive sensor 10 is, for example, a sheet-like device that is wrapped around arm 101. The capacitive sensor 10 may be attached to other arms or all arms, or it may be attached to the end effector 104. By providing such a capacitive sensor 10 to the robot 100, a collaborative robot that works in cooperation with humans can be realized.

[0024] As shown in Figures 2 and 3, the capacitance sensor 10 can be in a wrapped state, where it is wound around the outer surface of the arm 101 in a ring shape in the circumferential direction, and in an unfolded state (not shown) where it is spread out on a plane. A pair of hook fasteners 11 and 12 are attached to both ends of the sheet-like capacitance sensor 10, and the capacitance sensor 10 can be attached to and detached from the arm 101 by the hook fasteners 11 and 12.

[0025] Figure 4 shows a schematic block configuration of the detection system according to this embodiment. As shown in the figure, the detection system 1 comprises a capacitance sensor 10 and a processing unit 2 to which it is connected. The capacitance sensor 10 is a sensor for measuring the capacitance generated between it and an object (such as a person or object), and detects the approach or contact of the object based on the measured capacitance (and its changes). The controller 110 of the robot 100 is connected to the processing unit 2.

[0026] The processing unit 2 is a device for detecting an object based on the capacitance measurement value measured by the capacitance sensor 10, the reference value (Base value) which is the reference capacitance in the capacitance sensor 10, and the approach and contact threshold values ​​set in the capacitance sensor 10. The processing results of the processing unit 2 are input to the controller 110 of the robot 100, which then enables various operational controls, such as operating the robot 100 in a deceleration mode to reduce its operating speed when an object is approaching, and operating the robot 100 in an emergency stop mode to make an emergency stop when an object makes contact.

[0027] The processing unit 2 is connected to the capacitance sensor 10 and includes a determination unit 21 that determines whether the object is in a non-proximity state, a proximity state, or a contact state based on the measured value, reference value (Base value), and each threshold (described later) output from the capacitance sensor 10; a calibration unit 22 that performs calibration of the reference value at predetermined intervals when the determination unit 21 determines that the object is in a non-proximity state, and does not perform calibration when the determination unit 21 determines that the object is in a proximity state or a contact state; a correction unit 23 that creates and outputs a correction value when the determination unit 21 determines that the object is in a contact state; and a processing unit 24 that performs correction processing to correct the reference value by the correction value (specifically, by adding the correction value to the reference value) when the correction value is output from the correction unit 23.

[0028] Next, the control flow (i.e., operation control) by the processing unit 2 will be explained based on the flowchart in Figure 5, with reference to the operation graph in Figure 6.

[0029] In Figure 6, the thick line graph shows an example of the change in capacitance measured by the capacitance sensor 10. Also in the same figure, the four thin, stepped lines indicate the approach and contact thresholds set for the capacitance sensor 10. The approach threshold has an approach ON threshold applied when the object transitions to an approach state and an approach OFF threshold (< approach ON threshold) applied when the object moves away from the approach state. The contact threshold has a contact ON threshold applied when the object transitions to a contact state and a contact OFF threshold (< contact ON threshold) applied when the object moves away from the contact state. The thresholds are set in descending order of value (i.e., from top to bottom in Figure 6): contact ON threshold, contact OFF threshold, approach ON threshold, and approach OFF threshold.

[0030] Furthermore, in Figure 6, the thin line graph below the proximity OFF threshold shows the Average value (Ave value), which is the average value of capacitance measurements over a certain period. The thick, stepped line overlapping with the Average value is the reference value (Base value) set based on the Average value. In the example shown in Figure 6, calibration and correction processing is performed on the reference value (Base value), and also on each of the four thresholds (details will be described later).

[0031] When the control flow program starts, first, in step S1 in Figure 5, the capacitance sensor 10 (Figures 1 and 4) measures the capacitance (see "Normal Operation Section I" on the far left of Figure 6). The measured value output from the capacitance sensor 10 is input to the determination unit 21 of the processing unit 2 (Figure 4). Once the capacitance measurement is complete, the program proceeds to step S2.

[0032] In step S2, the determination unit 21 (Figure 4) performs a process in which the difference between the input measurement value and the reference value (Base value), which is the reference capacitance of the capacitance sensor 10, is used as the determination value (i.e., the difference is substituted into the determination value). The reference value (Base value) is set based on the Average value, which is the average value of the capacitance measurement values ​​over a certain period, as described above.

[0033] Furthermore, in step S2 and beyond, the determination of whether the detected object is in a non-proximity, proximity, or contact state is made based on this determination value. That is, as will be described later, the determination of whether the object is in a non-proximity, proximity, or contact state is made by comparing the determination value with the threshold value. Note that in Figure 6, for illustrative purposes, a graph of measured values ​​is shown instead of determination values, but each threshold value is positioned at the location corresponding to the measured value. Therefore, in the following explanation, the flowchart in Figure 5 will be explained using the determination value, but in the operation graph in Figure 6, the determination value can be rephrased as the measured value.

[0034] Next, in step S3, it is determined whether the object (a person or object such as a worker) is approaching or in contact with the object. Here, the object is determined to be approaching (i.e., in an approaching state) when the judgment value rises above the approach ON threshold (Figure 6) (in the same figure, the intersection of the approach ON threshold and the graph is labeled "approaching ON"). Conversely, if the judgment value does not exceed the approach ON threshold, the object is in a non-approaching state. Also, the object changes from an approaching state to a non-approaching state while moving away when the judgment value falls below the approach OFF threshold (Figure 6) (in the same figure, the intersection of the approach OFF threshold and the graph is labeled "approaching OFF"). Similarly, the object is determined to be in contact (i.e., in a contacting state) when the judgment value rises above the contact ON threshold (Figure 6) (in the same figure, the intersection of the contact ON threshold and the graph is labeled "contact ON"). Furthermore, the transition from a contact state to a non-contact state during separation occurs when the judgment value falls below the contact OFF threshold (Figure 6) (in the same figure, the intersection of the contact OFF threshold and the graph is labeled "contact OFF").

[0035] In step S3, if it is determined that the object is neither approaching nor in contact with the object, i.e., in a non-approaching state, the determination in step S3 becomes "No," and the process proceeds to step S4. Here, the non-approaching state of the object means, as described above, that the judgment value does not exceed the approach ON threshold while the object is approaching (or, while the object is moving away, the judgment value does not exceed the approach OFF threshold) (see "Normal Operation Sections I and II" in Figure 6).

[0036] In step S4, the measurement count (n) is incremented (i.e., 1 is added to n), and the Average value (the average value of capacitance measurements over a certain period) is updated. Next, in step S5, it is determined whether the number of measurements exceeds the specified number. If the number of measurements exceeds the specified number, the determination in step S5 becomes "Yes," and the process proceeds to step S6.

[0037] In step S6, calibration is performed. Generally, capacitance measured by a capacitance sensor fluctuates due to external factors such as ambient temperature, humidity, and the influence of other equipment, even when the object is not close. Therefore, calibration is performed to prevent the measured value from being affected by such fluctuations in capacitance due to external factors. In step S6, the calibration unit 22 (Figure 4) performs calibration by substituting the updated Average value into the reference value (Base value) to correct and update the reference value (Base value) (see "Normal Operating Interval I" in Figure 6). In this example, the reference value (Base value) is corrected to the positive side (i.e., the upper side in Figure 6). In this example, the calibration unit 22 also performs calibration not only on the reference value (Base value) but also on each threshold value (see "Normal Operating Interval I" in Figure 6).

[0038] Next, in step S7, the correction function is enabled and the correction flag is set to 0. Then, in step S8, the measurement count is set to 0. After the processing in step S8, the process proceeds to step S9.

[0039] Furthermore, if it is determined in step S5 that the number of measurements has not exceeded the specified number, the determination in step S5 will be "No," and the process will proceed to step S9.

[0040] In step S9, it is determined whether or not to terminate the program. If it is determined not to terminate, the program returns to step S1 and performs the next capacitance measurement. Alternatively, in step S9, if it is determined to terminate the program, such as by pressing the program termination button or turning off the robot's power, the program will terminate.

[0041] On the other hand, if it is determined in step S3 that the object is approaching or in contact with it, the determination in step S3 becomes "Yes" and the process proceeds to step S10. In step S10, it is determined whether or not the object is in contact with the object.

[0042] In step S10, if it is determined that the object is in contact, the determination in step S10 becomes "Yes" and the process proceeds to step S11. Here, the object being in contact means, as described above, that the judgment value exceeds the contact ON threshold while the object is approaching (or, while the object is moving away, the judgment value exceeds the contact OFF threshold). In step S11, it is determined whether the correction function is enabled (i.e., whether the correction flag is equal to 0). In step S11, if it is determined that the correction flag is enabled, the determination in step S11 becomes "Yes" and the process proceeds to step S12.

[0043] In step S12, a correction process is performed to correct the reference value (Base value). The reasons for performing the correction process are as follows: In capacitance sensor measurements, the measured capacitance may change due to state changes caused by contact with the object. If the measured capacitance exceeds the contact OFF threshold due to the state change caused by contact, the contact state will remain maintained. Therefore, a correction process is performed to facilitate the return to a normal judgment state when the object becomes non-proximity after the state change caused by contact.

[0044] In this case, the correction unit 23 (Figure 4) creates and outputs a correction value based on the increase in capacitance due to contact with the object. The output correction value is input to the processing unit 24 (Figure 4). The processing unit 24 performs a correction process to correct the base value by adding the correction value to the base value and substituting the result back into the base value. As a result of the correction process, the base value increases and is corrected to the positive side (see the "Correction Processing Interval" in the middle of Figure 6).

[0045] The correction value created by the correction unit 23 is set to a region (capacitance) smaller than the region (capacitance) between the proximity ON threshold and the proximity OFF threshold, so as not to affect the proximity determination.

[0046] Furthermore, in this example, the contact ON threshold, contact OFF threshold, proximity ON threshold, and proximity OFF threshold are each set to have a predetermined difference from the reference value. Therefore, the correction processing of the reference value (Base value) by the correction unit 23 causes each threshold to rise with respect to the judgment value (measured value), effectively correcting it to the positive side (see "Correction Processing Interval" in Figure 6).

[0047] Furthermore, the difference between the approach ON threshold and the approach OFF threshold, and the difference between the contact ON threshold and the contact OFF threshold, remain constant before and after the correction process. That is, for each contact threshold (ON / OFF threshold), the increment (correction value) due to the correction process is the same, and similarly, for each approach threshold (ON / OFF threshold), the increment (correction value) due to the correction process is the same.

[0048] Next, in step S13, the correction function is disabled and the correction flag is set to 1. After the processing in step S13, the program proceeds to step S8. Also, if it is determined in step S11 that the correction flag is not valid (the correction flag is not 0), the determination in step S11 becomes "No", and the program proceeds to step S8.

[0049] Here, in step S11, the statement "Yes only for the first contact" is to ensure that correction processing is always performed when there is initial contact with the object. The reason for specifying "only" is that if the correction processing were performed every time a contact determination is made while the contact state is continuous, the correction values ​​added to the Base value would accumulate, resulting in a smaller determination value. This would cause the contact state to be released and the object to be judged as approaching even in cases where the contact state should not be released. This is to avoid such a situation.

[0050] As shown in steps S11 to S13 above, in this contact state flow, calibration is not performed (standby state), and the updating of the average value is also stopped. This maintains the contact detection state.

[0051] On the other hand, if it is determined in step S10 that the object is not in contact (i.e., in approaching state), the determination in step S10 becomes "No" and the process proceeds to step S8. Here, being in an approaching state means, as described above, that the judgment value exceeds the approach ON threshold while the object is approaching (or that the judgment value exceeds the approach OFF threshold while the object is moving away). More specifically, it is the state between when the judgment value reaches the approach ON threshold and when it reaches the contact ON threshold, or between when the judgment value reaches the contact OFF threshold and when it reaches the approach OFF threshold.

[0052] As shown in steps S10→S8 above, in this approach state flow, no correction processing is performed, calibration is not executed (standby state), and the updating of the average value is stopped.

[0053] Furthermore, when the object transitions from an approaching state to a non-approaching state while moving away, in the flowchart of Figure 5, Step S10 → S8 → S9 → [S1 → S2 → S3 → S4 → S5 → S6 → S7 → S8 → S9] → [] Repeat Through this flow, calibration is performed repeatedly, so the correction value set at the time of contact with the object is reset in stages (see "Normal Operation Section II" in Figure 6, where calibration is performed three times in the non-proximity state).

[0054] Thus, according to this embodiment, calibration and correction processes are not performed continuously during capacitance measurement, enabling the detection of non-proximity, proximity, and contact with an object to be performed using a simple system.

[0055] Furthermore, according to this embodiment, if it is determined that a contact state is occurring, a correction process is performed on the reference value (Base value), and then, if it is determined that a non-proximity state is occurring, calibration is performed, making it easier to return to a normal state even if a state change occurs due to contact.

[0056] Each process in the detection system 1 described above (i.e., each control for executing the detection method) is stored in the form of a program (detection program) in, for example, a memory unit (not shown) provided by the detection system 1, and each process is executed when a computer (not shown), such as a processor in the processing unit 2, reads and executes this program. Here, the memory unit is composed of one or more of the following: volatile memory such as DRAM or SRAM, non-volatile memory such as flash memory, and magnetic storage device such as a hard disk drive.

[0057] [First variation] In the above embodiment, an example was shown in which not only the reference value (Base value) but also the threshold value was corrected (in this case, corrected to the positive side) during the correction process. However, in the present invention, only the reference value (Base value) may be corrected.

[0058] [Second variation] In the above embodiment, an example was shown in which the reference value (Base value) and threshold value were corrected to the positive side during the correction process, but the application of the present invention is not limited to this. The measured value may also be corrected to the negative side (conversely, if the reference value (Base value) and threshold value are corrected to the negative side, the measured value will be corrected to the positive side). In this case as well, the correction value is reset in stages by repeated calibration executions, similar to the above embodiment.

[0059] [Other variations] The embodiments and modifications described above should be considered in all respects merely as examples of the invention and not as limiting. Those skilled in the art to which the invention relates can construct various modifications and other embodiments that employ the principles of the invention, without deviating from the spirit and essential features of the invention, by considering the teachings described above, even if not explicitly stated herein.

[0060] [Other application examples] In the above embodiments and their respective modifications, a vertical articulated robot was used as an example of an object to which the detection system according to the present invention is applied. However, the detection system according to the present invention may also be applied to other robots, such as horizontal articulated robots, SCARA robots, and various other types of robots, as well as to the movable parts of industrial vehicles (forklifts, cranes, hydraulic excavators, etc.). Furthermore, it may be applied to automated guided vehicles (AGVs) and autonomous mobile robots (AMRs), and can even be applied to service robots (serving robots) used for serving and clearing food in restaurants and the like.

[0061] In the case of AGVs, AMRs, and food delivery robots, even if they do not have movable parts such as robotic arms, there is a risk of approaching or coming into contact with people or objects as the vehicle or robot itself moves. Therefore, by attaching capacitive sensors to the bumper, main body, or torso, a detection system according to the present invention can be constructed. Furthermore, it is not limited to robots, but can also be applied to movable parts of movable equipment and devices such as doors. [Industrial applicability]

[0062] This invention is useful for detection systems that detect proximity / contact between objects such as moving parts of machinery and people or objects such as operators. [Explanation of Symbols]

[0063] 1: Detection System 2: Processing unit 21: Judgment part 22: Calibration section 23: Correction section 24: Processing Unit 10: Capacitive sensor (sensor) [Prior art documents] [Patent Documents]

[0064] [Patent Document 1] Japanese Patent Publication No. 7420374 (see claims 1, 6, 7, paragraphs

[0007] ,

[0011] ,

[0026] ,

[0046] ,

[0048] and Figures 1 and 4)

Claims

1. A detection system for detecting an object, A sensor for measuring the capacitance generated between the object and the aforementioned object, The apparatus comprises a processing device that performs object detection processing based on the measured capacitance value obtained by the sensor and a reference value which is a reference capacitance in the sensor, The aforementioned processing device A determination unit that determines whether the object is in a non-approach state, an approach state, or a contact state based on the measured value, the reference value, and the approach and contact thresholds set for the sensor, A calibration unit which performs calibration of the reference value when the determination unit determines that the state is not close, and does not perform calibration when the determination unit determines that the state is close, and when the state is in contact, A correction unit that creates and outputs a correction value when the contact state is determined by the determination unit, When the correction unit outputs the correction value, the processing unit performs a correction process to correct the reference value or measured value using the correction value, A detection system equipped with [the following features].

2. In claim 1, When the correction value is output from the correction unit, the threshold values ​​are corrected using the correction value. A detection system characterized by the following:

3. In claim 1, When the correction unit outputs the correction value, the correction value is reset in stages when the calibration is performed upon transitioning to the non-proximity state. A detection system characterized by the following:

4. In claim 1, The approach threshold comprises an approach ON threshold applied when the object transitions to the approach state and an approach OFF threshold applied when the object moves away from the approach state. The threshold for contact includes a contact ON threshold applied when the object transitions to the contact state and a contact OFF threshold applied when the object moves away from the contact state. A detection system characterized by the following:

5. In claim 4, When the correction unit outputs the correction value, the correction value is added to each of the thresholds to correct them, and the difference between the approach ON threshold and the approach OFF threshold, and the difference between the contact ON threshold and the contact OFF threshold remain constant before and after the correction. A detection system characterized by the following:

6. In claim 1, When the aforementioned non-proximity state is determined, the calibration is performed using the average value of the measured values ​​over a certain period as the new reference value. A detection system characterized by the following:

7. In claim 1, The determination unit uses the difference between the measured value and the reference value as a determination value, and determines whether the object is in the non-approach state, the approach state, or the contact state by comparing the determination value with each threshold value. A detection system characterized by the following:

8. In claim 1, The sensor is for measuring the capacitance generated between the robot or movable body and the object. A detection system characterized by the following:

9. A detection method for detecting an object, The capacitance generated between the object and the sensor is measured by a sensor. Based on the measured capacitance value measured by the sensor, the reference value which is the reference capacitance in the sensor, and the approach and contact threshold values ​​set in the sensor, it is determined whether the object is in a non-approach state, an approach state, or a contact state. When the non-proximity state is determined, the calibration of the reference value is performed; when the proximity state is determined and when the contact state is determined, the calibration is not performed; and when the contact state is determined, a correction value is created and output. When the aforementioned correction value is output, the reference value or measured value is corrected using that correction value. A detection method characterized by the above.

10. In claim 1, When the aforementioned correction value is output, the threshold value is added to correct the threshold. A detection method characterized by the above.

11. In claim 1, When the aforementioned correction value is output, the said correction value is reset stepwise during the calibration when the state transitions to the non-proximity state. A detection method characterized by the above.

12. A detection program for causing a computer to execute the detection method described in any one of claims 9 to 11.

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