Nurse call system

Abstract

This system provides a nurse call system that can detect patient-induced alerts more accurately than conventional systems. [Solution] The system includes a camera 8 that images the area around the bed, including the bed itself, and a millimeter-wave radar device 9 equipped with a millimeter-wave antenna 24 that inputs and outputs wireless signals to and from the area around the bed, including the bed itself. When a warning activation is detected based on the image captured by the camera 8, if the similarity of the detection is less than a second threshold, the system determines whether the detection is correct or incorrect based on the analysis results of the millimeter-wave radar device 9. On the other hand, if the similarity is equal to or greater than the second threshold, the system determines that the detection is correct.

Description

Technical Field

[0001] The present invention relates to a nurse call system having a function of checking a patient's condition based on imaging by a camera and detection by a millimeter-wave radar device.

Background Art

[0002] As a conventional nurse call system, there is one having a function of checking a patient's condition by a camera that images a patient on a bed. For example, in the nurse call system described in Patent Document 1, when a situation where a patient gets up on the bed or leaves the bed is detected by the camera, the occurrence of the situation is notified to the nurse call master unit, and it is configured to be notified in the nurse call master unit.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the nurse call system described in Patent Document 1, since the patient's condition is checked only based on the video imaged by the camera, there is room for improvement in terms of reliability.

[0005] Therefore, the present invention has been made in view of the above problems, and an object thereof is to provide a nurse call system capable of detecting a patient's attention-calling operation more accurately than before.

Means for Solving the Problems

[0006] To achieve the above objective, the invention described in claim 1 of the present invention comprises a nurse call sub-unit for a patient to call a nurse, a nurse call master unit for responding to calls from the nurse call sub-unit, a control unit for controlling communication between the nurse call sub-unit and the nurse call master unit, a camera for imaging the area around the bed, including the bed itself, and a control means, wherein the control means compares feature quantities obtained from images captured by the camera with pre-learned feature quantities to determine similarity and detects a predetermined attention trigger by the patient based on the similarity, and comprises a millimeter-wave radar device equipped with a millimeter-wave antenna that inputs and outputs wireless signals toward the area around the bed, including the bed itself, and a millimeter-wave analysis unit that analyzes the signals input via the millimeter-wave antenna, wherein when an attention trigger is detected based on images captured by the camera, the control means determines whether the detection is correct or incorrect based on the analysis results of the millimeter-wave radar device if the similarity related to the detection is less than a certain threshold, while determining that the detection is correct if the similarity is above a certain threshold.

[0007] Furthermore, in order to achieve the above objective, the invention described in claim 2 of the present invention comprises a nurse call sub-unit for a patient to call a nurse, a nurse call master unit for responding to calls from the nurse call sub-unit, a control unit for controlling communication between the nurse call sub-unit and the nurse call master unit, a millimeter-wave radar device equipped with a millimeter-wave antenna that outputs and inputs wireless signals toward the area around the bed, including the bed, and a millimeter-wave analysis unit that analyzes the signals input via the millimeter-wave antenna, and a control means, wherein the control means uses feature quantities obtained from the analysis results of the millimeter-wave radar device and pre-learned features A nurse call system that determines the degree of similarity by comparing it with a given feature quantity and detects a predetermined alert trigger by a patient based on the degree of similarity, comprising a camera equipped with an imaging unit that images the area around the bed, including the bed itself, and an image analysis unit that analyzes the images captured by the imaging unit, wherein the control means, when an alert trigger is detected based on the analysis results of a millimeter-wave radar device, determines whether the detection is correct or incorrect based on the analysis results of the camera if the degree of similarity related to the detection is below a certain threshold, while determining that the detection is correct if the degree of similarity is above a certain threshold. [Effects of the Invention]

[0008] According to the present invention, the system comprises a camera and a millimeter-wave radar device. When a warning trigger is detected based on the image captured by the camera, the control means determines whether the detection is correct or incorrect based on the analysis results of the millimeter-wave radar device if the similarity related to the detection is below a certain threshold (Claim 1). When a warning trigger is detected based on the analysis results of the millimeter-wave radar device, the control means determines whether the detection is correct or incorrect based on the analysis results of the camera if the similarity related to the detection is below a certain threshold (Claim 2). On the other hand, if the similarity is above a certain threshold, the control means determines that the detection is correct. Therefore, it is possible to detect warning triggers by patients more accurately than in the conventional system, which relied solely on the image captured by the camera. [Brief explanation of the drawing]

[0009] [Figure 1]This is an explanatory diagram showing the overall configuration of the nurse call system. [Figure 2] This is a block diagram of the camera. [Figure 3] This is a block diagram of a millimeter-wave radar system. [Figure 4] This is a flowchart for detecting patient-induced alerts in the nurse call system. [Modes for carrying out the invention]

[0010] The following describes in detail, based on the drawings, a nurse call system that is one embodiment of the present invention.

[0011] Figure 1 is an explanatory diagram showing the overall configuration of the nurse call system. Figure 2 is a block diagram of camera 8. Figure 3 is a block diagram of millimeter-wave radar device 9. Figure 4 is a flowchart related to the detection of patient alert activation by the nurse call system.

[0012] The nurse call system comprises nurse call sub-units 1, 1... installed at each bedside for patients to call a nurse, corridor lights 2, 2... installed near the entrance to the patient room that notify the patient of a call operation by the nurse call sub-unit 1 by flashing, etc., and display patient information in the patient room, a nurse call master unit 3 installed at the nurse station, etc., that notifies the patient of a call operation from the nurse call sub-units 1, 1... and responds to such calls, mobile terminals 4, 4... such as smartphones carried by each nurse to respond to calls from patients, base stations 5, 5... such as access points that communicate with the mobile terminals 4, 4..., a switch 6 for managing communication via the base station 5, a controller 7 for controlling calls / communications between each device, and cameras 8, 8... and millimeter-wave radar devices 9, 9... installed at each bedside to check the condition of the patient on or around the bed. Furthermore, the corridor lights 2, 2, ..., the nurse call master unit 3, and the exchange unit 6 are connected to the control unit 7 via LAN line L1, each nurse call slave unit 1 is connected to the corridor light 2 via transmission line L2, and each camera 8 is connected to the corridor light 2 via transmission line L3.

[0013] Here, we will describe in detail how to check the patient's condition using the camera 8 and millimeter-wave radar device 9, which are the essential components of the present invention. Camera 8 includes a camera CPU 11 that controls its own movements, an imaging unit 15 that images the bed and its surroundings, an image analysis unit 12 that analyzes the images captured by the imaging unit 15, a determination unit 18 that determines the patient's movements based on the analysis results from the image analysis unit 12 and the analysis results from the millimeter-wave radar device 9, as described later, a communication interface 14 to which the transmission line L3 is connected, a speaker 16 that emits a predetermined alarm sound, a storage unit 13 that stores various thresholds, etc., and an interface 17 for connecting the millimeter-wave radar device 9.

[0014] The millimeter-wave radar device 9 includes a radar CPU 21 that controls its own operation, a millimeter-wave antenna 24 that inputs and outputs millimeter waves for object detection, a millimeter-wave analysis unit 22 that analyzes the signals input to the millimeter-wave antenna 24, a storage unit 23 that stores various thresholds, etc., and an interface 25 for connecting the camera 8.

[0015] The detection of patient alert-activated actions using the aforementioned camera 8 and millimeter-wave radar device 9 will be explained according to the flowchart shown in Figure 4. First, the camera 8 continuously captures images of the bed and its surroundings using the imaging unit 15, and the images are analyzed by the video analysis unit 12. Based on the analysis results, the camera detects predetermined attention-raising actions performed by the patient. Specifically, when a patient in bed gets up from a prone position, the camera detects the patient's movement as a getting-up action, which is one of the attention-raising actions. Similarly, when a patient moves from the bed to outside the bed, the camera detects the patient's movement as an exit from bed, which is another attention-raising action. Furthermore, as described in Japanese Patent Publication No. 2014-229266, the detection of these attention-raising actions is performed by comparing the features obtained from the captured images with pre-trained features to determine their similarity. The determination unit 18 determines that an attention-raising action has been detected when the similarity exceeds a predetermined first threshold.

[0016] Meanwhile, the millimeter-wave radar device 9 constantly outputs a wireless signal from the millimeter-wave antenna 24 toward the bed and its surroundings, and also inputs the reflected signal, which is then analyzed by the millimeter-wave analysis unit 22. Based on the analysis results, the device detects the patient's position. In other words, it detects whether or not the patient is on the bed, and the patient's position on the bed, or in other words, the patient's posture.

[0017] Then, when camera 8 detects the aforementioned alert-triggering action based on the analysis results of the video analysis unit 12 (determined as YES in S1), the judgment unit 18 determines whether the similarity related to this detection exceeds a second threshold (a specific threshold) which is higher than the first threshold (S2). If the result of this determination is that the similarity is equal to or greater than the second threshold (determined as NO in S2), it is determined that the patient has taken an alert-triggering action, that is, the detection of the alert-triggering action by camera 8 is correct, and the judgment result is notified to the nurse call master unit 3 to be announced on the nurse call master unit 3, and an alarm operation is performed in which a predetermined alarm sound is emitted from speaker 16 (S4).

[0018] On the other hand, when the similarity is less than the second threshold value (judged as YES in S2), a position request signal is transmitted to the millimeter-wave radar device 9. Also, when the millimeter-wave radar device 9 receives the position request signal, it returns patient position information including the position of the patient based on the analysis result by the millimeter-wave analysis unit 22 to the camera 8. Then, the camera 8 determines, in the determination unit 18, whether or not the position of the patient corresponding to the attention-arousing operation has been detected in the millimeter-wave radar device 9 based on the received patient position information (S3). Specifically, when a rising motion is detected in S1, it is determined in S3 whether or not the posture of the patient on the bed is in a predetermined rising posture. Also, when a getting-out-of-bed motion is detected in S1, it is determined in S3 whether or not the position of the patient is outside the bed. And when the camera 8 determines that the position of the patient is at a position corresponding to the attention-arousing operation (judged as YES in S3), it determines that the detection of the attention-arousing operation by the camera 8 based on the analysis result in the millimeter-wave radar device 9 is correct, notifies the determination result to the nurse call master unit 3 to cause the nurse call master unit 3 to give an alarm, and executes an alarm operation of sounding a predetermined alarm sound from the speaker 16 (S4).

[0019] Note that although the camera 8 has detected an attention-arousing operation, if the similarity is less than the second threshold value and it is determined that the position of the patient in the millimeter-wave radar device 9 is not at a position corresponding to the attention-arousing operation (judged as NO in S3), it is determined that the detection of the attention-arousing operation by the camera 8 based on the analysis result in the millimeter-wave radar device 9 is incorrect, and alarm operations such as notification to the nurse call master unit 3 and sounding of an alarm sound are not executed. Also, when silencing the alarm sound being sounded from the speaker 16, an unillustrated button provided on the nurse call slave unit 1 may be operated. Furthermore, the notification operation in the nurse call master unit 3 can also be stopped by operating a button or the like on the nurse call master unit 3.

[0020] According to the nurse call system having the above configuration, it includes a camera 8 that images the surroundings of the bed including the area on the bed, and a millimeter-wave radar device 9 having a millimeter-wave antenna 24 that inputs and outputs wireless signals toward the surroundings of the bed including the area on the bed. When an alert operation is detected based on the video imaged by the camera 8, if the similarity related to the detection is less than the second threshold value, the correctness of the detection is determined based on the analysis result of the millimeter-wave radar device 9. On the other hand, if the similarity is greater than or equal to the second threshold value, the detection is determined to be correct. Therefore, it is possible to detect an alert operation by the patient more accurately than in the past, which was based only on the video imaged by the camera.

[0021] Note that the nurse call system according to the present invention is not limited to the aspects of the above embodiment. Not only the overall configuration of the nurse call system, but also the configuration related to confirming the patient's condition by the millimeter-wave radar device, etc., can be appropriately changed as needed without departing from the spirit of the present invention.

[0022] For example, in the above embodiment, the position of the patient can be detected by the millimeter-wave radar device, but the movement of the patient may also be detected by the millimeter-wave radar device. When a millimeter-wave radar device capable of detecting the movement of the patient is adopted in this way, the control related to the detection of the alert operation by the patient is as follows.

[0023] First, in the millimeter-wave radar device, a wireless signal is constantly output from the millimeter-wave antenna toward the bed and the surroundings of the bed, and the reflected signal is input and analyzed by the millimeter-wave analysis unit. It is assumed that the movement of the patient is detected based on the analysis result. Regarding the detection of the movement of a person using this millimeter-wave radar, it can be performed by a method such as that described in Japanese Patent Application Laid-Open No. 2024-109538. Also, the determination unit provided in the camera in the above embodiment is provided in the millimeter-wave radar device.

[0024] Here, as in the above embodiment, if the camera detects a patient's attention-raising action and the similarity to the detection is less than the second threshold, the camera transmits an operation confirmation signal to the millimeter-wave radar device, including the content of the detected attention-raising action. On the other hand, when the millimeter-wave radar device receives the operation confirmation signal, it uses a determination unit to determine whether the same action as the attention-raising action detected by the camera has been detected, based on the analysis results of the millimeter-wave analysis unit, within a predetermined time before and after the time the operation confirmation signal was received (for example, within 5 seconds). If the millimeter-wave radar device also determines that the same action as the attention-raising action detected by the camera has been detected, the millimeter-wave radar device sends an alert signal back to the camera. Furthermore, upon receiving the alert signal, the camera notifies the nurse call master unit 3 to make an announcement on the nurse call master unit 3 and performs an alarm operation by sounding a predetermined alarm sound from the speaker 16. On the other hand, if the millimeter-wave radar system determines that it has not detected the same alert activation action as detected by the camera, it sends a clear signal back to the camera, and the camera does not perform the aforementioned alarm action.

[0025] As described above, in a nurse call system that enables the detection of patient movements using a millimeter-wave radar device, similar to the nurse call system of the above embodiment, if the similarity of the detection of a patient's alert action by the camera falls below the second threshold, the accuracy of the detection is determined based on the analysis results of the millimeter-wave radar device. Therefore, it is possible to detect patient's alert actions more accurately than in the conventional system which relied solely on images captured by the camera.

[0026] Furthermore, while the above embodiments and modified examples are configured to refer to the analysis results of the millimeter-wave radar device based on the analysis results of the image captured by the camera, the opposite configuration is also possible, where the camera's image analysis results are referred to based on the analysis results of the millimeter-wave radar device. That is, in the millimeter-wave radar device, similar to the camera in the above embodiments, the similarity is determined by comparing the feature quantities obtained from the analysis results of the millimeter-wave radar device with pre-trained feature quantities, and a predetermined attention trigger by the patient is detected based on this similarity. When an attention trigger is detected in the millimeter-wave radar device, it is determined whether the similarity related to the detection is above a certain threshold, and if it is above the certain threshold, it is determined that the detection of an attention trigger in the millimeter-wave radar device is correct, and a predetermined notification action is performed. On the other hand, if it is below the certain threshold, the image analysis results from the camera are referred, and the notification action is performed only if the corresponding attention trigger is also detected in the camera. In this type of nurse call system, as with the nurse call system of the above embodiment, it is possible to detect patient alert activations more accurately than in conventional systems that relied solely on images captured by a camera.

[0027] Furthermore, as another example of modification, in the above embodiment, the speaker installed on the camera is configured to function as a notification means, but the speaker on the nurse call sub-unit could also be used as a notification means, or the corridor light could be turned on / flashed as a notification means, and the specific structure of the notification means can be modified as appropriate.

[0028] Furthermore, the video analysis unit and millimeter-wave analysis unit may be installed in corridor lights or control units instead of cameras or millimeter-wave radar equipment. Furthermore, although the above embodiment provides control means to the camera, the control means may also be provided to the millimeter-wave radar device, or to the corridor light or control unit. In addition, instead of configuring the camera and millimeter-wave radar system as separate devices, it is also possible to configure them as an integrated device, that is, a device that includes both an imaging unit and a millimeter-wave antenna. [Explanation of Symbols]

[0029] 1. Nurse call sub-unit, 2. Corridor light, 3. Nurse call master unit, 7. Control unit, 8. Camera, 9. Millimeter-wave radar device, 11. Camera CPU (control means), 12. Image analysis unit, 16. Speaker, 18. Judgment unit (control means), 21. Radar CPU, 22. Millimeter-wave analysis unit, 24. Millimeter-wave antenna.

Claims

1. The system comprises a nurse call sub-unit for the patient to call a nurse, a nurse call master unit for responding to calls from the nurse call sub-unit, a control unit for controlling communication between the nurse call sub-unit and the nurse call master unit, a camera for imaging the area around the bed, including the bed itself, and control means. The control means is a nurse call system that compares feature quantities obtained from images captured by the camera with pre-learned feature quantities to determine similarity, and detects a predetermined alert activation action by the patient based on the similarity, The device includes a millimeter-wave radar system that inputs and outputs wireless signals toward and around the bed, including the bed itself, and a millimeter-wave analysis unit that analyzes the signals input via the millimeter-wave antenna. When the control means detects the warning activation based on the image captured by the camera, if the similarity related to the detection does not fall below a certain threshold, it determines whether the detection is correct or incorrect based on the analysis results of the millimeter-wave radar device, A nurse call system characterized in that it determines the detection is positive if the similarity is greater than or equal to a specific threshold.

2. The system comprises a nurse call sub-unit for patients to call a nurse, a nurse call master unit for responding to calls from the nurse call sub-unit, a control unit for controlling communication between the nurse call sub-unit and the nurse call master unit, a millimeter-wave radar device equipped with a millimeter-wave antenna that outputs and receives wireless signals toward and around the bed, including the bed itself, and a millimeter-wave analysis unit for analyzing signals received via the millimeter-wave antenna, and control means. The control means is a nurse call system that compares feature quantities obtained from the analysis results of the millimeter-wave radar device with pre-learned feature quantities to determine the similarity, and detects a predetermined alert activation action by the patient based on the similarity, The system includes a camera equipped with an imaging unit that captures images of the area around the bed, including the bed itself, and an image analysis unit that analyzes the images captured by the imaging unit. When the warning activation is detected based on the analysis results of the millimeter-wave radar device, if the similarity related to the detection does not fall below a certain threshold, the control means determines whether the detection is correct or incorrect based on the analysis results of the camera, A nurse call system characterized in that it determines the detection is positive if the similarity is greater than or equal to a specific threshold.

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