Fall detection method based on millimeter wave radar

Abstract

The invention discloses a falling detection method based on a millimeter wave radar, relates to the technical field of falling detection, and solves the technical problem that in the prior art, after a passage space is determined according to risk assessment, motion detection of a falling person cannot be carried out. Performing layout detection on the activity area of the falling detection personnel according to a millimeter wave radar technology, and obtaining a passing space in the activity area according to the layout detection; action recognition and early warning: after the passage space is determined, behavior action detection is performed on the fall detection personnel, and the real-time fall risk of the fall detection personnel is evaluated according to the behavior action detection; and spatial layout analysis: according to the spatial layout, obtaining a set object at the position where the tumble detection person has the tumble action, and according to the fact that the limb action of the person and the set object are connected and evaluated when the tumble detection person has the tumble action, deducing whether the tumble detection person needs to be balanced through the set object when the tumble detection person falls.

Description

Technical Field

[0001] The present invention relates to the technical field of fall detection, and in particular to a fall detection method based on millimeter wave radar. Background Art

[0002] Fall detection is a technology used to detect whether a person has fallen, and it is widely used in smart homes, healthcare and other fields. Millimeter-wave radar-based fall detection is a method that uses millimeter-wave radar technology to monitor and judge human falls. It has the advantages of being non-contact, high-precision, and not affected by light and occlusion.

[0003] However, in the prior art, when using millimeter-wave radar for fall detection, it is not possible to conduct risk assessment on the activity area of ​​the fall detection personnel, nor is it possible to detect the movements of the fallen personnel after determining the passage space based on the risk assessment. The efficiency of fall detection cannot be improved based on the movement collection points, which reduces the accuracy of fall risk detection. In addition, it is impossible to re-plan and control the layout of objects in the activity area based on fall movement detection.

[0004] In view of the above technical defects, a solution is now proposed. Summary of the invention

[0005] The purpose of the present invention is to solve the above-mentioned problems and to propose a fall detection method based on millimeter wave radar.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] The fall detection method based on millimeter wave radar, the fall detection method process is as follows:

[0008] Layout detection and annotation: Use millimeter-wave radar technology to perform layout detection on the activity area of ​​the fall detection personnel, and obtain the passage space within the activity area based on the layout detection;

[0009] Motion recognition warning: after determining the passage space, the behavior and motion of the fall detection personnel are detected, and the real-time fall risk of the fall detection personnel is evaluated based on the behavior and motion detection;

[0010] Spatial layout analysis: Based on the spatial layout, the set object at the position where the fall detection person falls is obtained. When the fall detection person falls, the person's body movements are connected and evaluated with the set object to infer whether the fall detection person needs to use the set object to maintain balance when falling.

[0011] As a preferred implementation of the present invention, the process of layout detection and annotation is as follows:

[0012] Set the signal wave emission point, expand the signal wave according to the millimeter wave radar to cover the activity area where the fall detection personnel are located, and determine the set objects in the activity area according to the continuous emission and reception of signal waves by the signal wave emission point, and obtain the shape information of each set object according to the change of the signal wave; after obtaining the shape information of each set object, obtain the space in the activity area except the space occupied by the set object, and mark it as the passage space; according to the continuity of the passage space, obtain the movement trajectory space of the fall detection personnel in the passage space and the corresponding connected passage destination;

[0013] The collected data include the ratio of the area of ​​the movement trajectory space of the fall detection personnel to the area of ​​the passage space, and the ratio of the movement trajectory distance in which the area of ​​the movement trajectory space of the fall detection personnel is greater than the area required for the fall detection personnel to move.

[0014] As a preferred embodiment of the present invention, if the area ratio of the moving trajectory space and the passing space exceeds the space area ratio threshold, or the moving trajectory distance ratio of the falling detection personnel's moving trajectory space area higher than the area required for the falling detection personnel to move does not exceed the moving trajectory distance ratio threshold, a high-risk signal is generated; if the area ratio of the moving trajectory space and the passing space does not exceed the space area ratio threshold, and the moving trajectory distance ratio of the falling detection personnel's moving trajectory space area higher than the area required for the falling detection personnel to move exceeds the moving trajectory distance ratio threshold, a low-risk signal is generated and sent to the guardian terminal.

[0015] As a preferred embodiment of the present invention, the process of motion recognition warning is as follows:

[0016] The center point of the person is obtained according to the body shape of the fall detection person, and the center of gravity is marked to obtain the center of gravity point; the moving point is obtained according to the body shape and moving movements of the fall detection person, and it is marked as a limb point according to the moving point and the moving position of the fall detection person; the position of the center of gravity point is counted when the fall detection person moves, and the center of gravity point at each moment when no fall occurs is linear in the activity area space, and the flapping trajectory of the limb points of the fall detection person when no fall occurs is collected in a reciprocating cycle and marked as a pendulum movement.

[0017] As a preferred embodiment of the present invention, the signal wave is used to identify the action of the fall detection personnel, and the instantaneous decrease speed peak value of the height of the center of gravity point of the fall detection personnel changing the linear shape and the increase span value of the swing amplitude of the limb point after the fall detection personnel corresponding to the limb point changes the pendulum action are collected:

[0018] If the instantaneous decrease speed peak value of the height of the center of gravity point of the fall detection personnel that changes the linear shape exceeds the decrease speed peak threshold, but the center of gravity point returns to the height of the linear shape at the adjacent moment; if the limb point of the fall detection personnel changes the pendulum motion at the corresponding limb point and exceeds the amplitude increase span threshold, but the swing amplitude of the corresponding pendulum motion at the adjacent moment drops to zero and then returns to the swing motion cycle;

[0019] When the above two situations occur at the same time, the real-time action state of the fall detection person is marked as a fall action and a stable balance state, and the action state is sent to the guardian;

[0020] If the instantaneous peak value of the speed reduction of the height of the center of gravity point where the fall detection person changes the straight line exceeds the peak value threshold of the speed reduction, and the center of gravity point has not recovered to the straight line height; if the increase span value of the swing amplitude of the limb point after the fall detection person changes the pendulum action of the corresponding limb point exceeds the amplitude increase span threshold, but the swing amplitude of the corresponding pendulum action at the adjacent moment drops to zero and has not recovered to the swing action cycle;

[0021] When any of the above two situations occurs, the real-time action status of the fall detection person is marked as a fall and the balance state is not stabilized, and the action status is sent to the guardian.

[0022] As a preferred embodiment of the present invention, the process of spatial layout analysis is as follows:

[0023] When a fall occurs and the person maintains balance, the overlapping time of the limb points of the fall detection person and the points of the set objects around the falling action location, as well as the time when the fall detection person maintains balance are collected, and the interval duration is obtained based on the time comparison, and is set as the object-assisted stabilization duration;

[0024] When a person is falling and has not maintained his balance, the distance value between the limb points of the fall detection person and the set objects around the falling action location is collected, and the distance value between the limb points of the fall detection person and the set objects around the falling action location is marked as the object auxiliary distance value.

[0025] As a preferred embodiment of the present invention, the object-assisted stabilization time and the object-assisted interval distance are analyzed:

[0026] If the object-assisted stabilization time exceeds the stabilization time threshold, the currently set object position is marked as a low-effect object position; if the object-assisted stabilization time does not exceed the stabilization time threshold, the currently set object position is marked as a high-effect object position;

[0027] If the object auxiliary interval exceeds the set interval distance threshold, and the limb points of the fall detection person have a tendency to move toward the set object when the fall action occurs, the current set object position is marked as the long-distance object position;

[0028] If the object assistance interval does not exceed the set interval distance threshold, and the limb points of the fall detection person have a tendency to move toward the set object when the fall action occurs, the current set object position is marked as an inefficient object position for assistance;

[0029] If the object assistance interval exceeds the set interval distance threshold, and the limb points of the fall detection personnel do not have a tendency to move toward the set object when the fall action occurs, the corresponding set object distance will be too far to assist in stabilization, and the current set object position will be marked as an unrelated object position;

[0030] If the object assistance interval does not exceed the set interval distance threshold, and the limb points of the fall detection person do not have a tendency to move toward the set object when a fall occurs, the corresponding set object will not meet the assistance stability requirements, and the current set object position will be marked as an invalid assistance object position.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] 1. In the present invention, the layout detection of the activity area of ​​the fall detection personnel is carried out according to the millimeter wave radar technology, and the passage space in the activity area is obtained according to the layout detection, so as to make a preliminary prediction of the fall of the fall detection personnel according to the passage space, and at the same time, the accuracy of the fall warning of the fall detection personnel can be improved according to the trajectory change of the passage space, so as to avoid the increase of the fall risk of the fall detection personnel due to the change of the passage space, and the warning is not given in time but after the fall action occurs, which cannot guarantee the passage safety of the fall detection personnel.

[0033] 2. In the present invention, after determining the passage space, the behavior and action detection is performed on the fall detection personnel, and the real-time fall risk of the fall detection personnel is evaluated based on the behavior and action detection, and an early warning is given in time when a fall risk action occurs, so that the fall detection personnel can get timely rescue after falling, avoiding the impact of the fall detection personnel's fall cannot be reduced.

[0034] 3. In the present invention, a set object is obtained at the position where the fall detection person occurs according to the spatial layout, and the person's body movements are connected and evaluated with the set object when the fall detection person occurs, and it is inferred whether the fall detection person needs to be balanced by the set object when falling, so as to plan the spatial layout according to the actual role of the set object, and at the same time, the space occupied by the set object at the current position is reset. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0036] Figure 1 is a flow chart of the overall method of the present invention;

[0037] Figure 2 This is a flow chart of the layout detection and annotation process in the present invention;

[0038] Figure 3 This is a flow chart of the action recognition warning process in the present invention. DETAILED DESCRIPTION

[0039] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0041] See also Figure 1 As shown, the fall detection method based on millimeter wave radar, the specific fall detection method process is as follows:

[0042] Through millimeter-wave radar, layout detection and marking are performed. According to millimeter-wave radar technology, layout detection is performed on the activity area of ​​the fall detection personnel. According to the layout detection, the passage space in the activity area is obtained, so as to make a preliminary prediction of the fall of the fall detection personnel according to the passage space. At the same time, according to the trajectory change of the passage space, the accuracy of the fall warning of the fall detection personnel can be improved, and the fall risk of the fall detection personnel caused by the change of the passage space is avoided. In addition, the warning is not given in time but after the fall action occurs, which cannot guarantee the safety of the fall detection personnel.

[0043] Action recognition and warning of fall detection personnel: after determining the passage space, the behavior and action detection of the fall detection personnel is carried out, and the real-time fall risk of the fall detection personnel is evaluated based on the behavior and action detection. When the fall risk action occurs, a warning is issued in time, so that the fall detection personnel can get timely assistance after falling, and avoid the fall detection personnel The impact of the fall cannot be reduced;

[0044] Falling action and spatial layout analysis: According to the spatial layout, the set object at the position where the fall detection person has a falling action is obtained. When the fall detection person has a falling action, the person's body movements are connected and evaluated with the set object, and it is inferred whether the fall detection person needs to use the set object to get balance when falling, so as to plan the spatial layout according to the actual role of the set object, and at the same time reset the space occupied by the set object at the current position;

[0045] See also Figure 2 As shown, the layout detection and annotation process is as follows:

[0046] Set the signal wave emission point, expand the signal wave according to the millimeter wave radar to cover the activity area where the fall detection personnel are located, and determine the set objects in the activity area according to the continuous emission and reception of signal waves by the signal wave emission point, and obtain the shape information of each set object according to the change of the signal wave, specifically the shape, height, length and other data;

[0047] After obtaining the shape information of each set object, obtain the space in the activity area except the space occupied by the set object and mark it as the passage space; obtain the movement trajectory space of the fall detection personnel in the passage space and the corresponding connected passage destination according to the continuity of the passage space; and perform all collection and marking;

[0048] The area ratio of the movement trajectory space of the fall detection personnel to the passage space is collected, and at the same time, the movement trajectory distance ratio of the movement trajectory space area of ​​the fall detection personnel is higher than the area required for the fall detection personnel to move is collected; it should be explained that the area of ​​the space is calculated based on the area occupied in the corresponding space; the area required for the movement of the fall detection personnel is calculated based on the steps of the fall detection personnel and the lateral step spacing; and the area ratio of the movement trajectory space of the fall detection personnel to the passage space, and the movement trajectory distance ratio of the movement trajectory space area of ​​the fall detection personnel is higher than the area required for the fall detection personnel to move are compared with the space area ratio threshold and the movement trajectory distance ratio threshold respectively: the threshold is expressed as the threshold value obtained by the personnel in this field during actual monitoring based on the analysis of the fall process of the same type of detection personnel in history;

[0049] If the area ratio of the movement trajectory space of the fall detection personnel and the passage space exceeds the space area ratio threshold, or the movement trajectory distance ratio of the movement trajectory space area of ​​the fall detection personnel higher than the area required for the fall detection personnel to move does not exceed the movement trajectory distance ratio threshold, it is inferred that the fall risk of the current activity area of ​​the fall detection personnel is high, and a high-risk signal is generated and sent to the guardian terminal. After receiving the high-risk signal, the guardian terminal sets the layout plan of the objects in the activity area where the fall detection personnel is located, and expands the passage space according to the needs of the actual destination;

[0050] If the area ratio of the movement trajectory space of the fall detection personnel to the passage space does not exceed the space area ratio threshold, and the movement trajectory distance ratio of the movement trajectory space area of ​​the fall detection personnel higher than the area required for the fall detection personnel to move exceeds the movement trajectory distance ratio threshold, it is inferred that the fall risk of the current activity area of ​​the fall detection personnel is low, and a low risk signal is generated and sent to the guardian terminal;

[0051] See also Figure 3 As shown in the figure, the action recognition warning process is as follows:

[0052] When determining the low-risk fall in the spatial area where the fall detection personnel are located, the movement of the fall detection personnel is identified and detected in real time, and the center point of the personnel is obtained according to the body shape of the fall detection personnel. When the fall detection personnel moves, the center of gravity is marked according to whether the position of the center point floats or not. That is, if the position of the center point floats, the point is collected again. If the position of the center point does not float, the center point is marked as the center of gravity point;

[0053] The moving points are obtained according to the body shape and movement of the fall detection person, and are marked as limb points according to the moving points and the moving positions of the fall detection person;

[0054] When the fall detection personnel moves, the position of the center of gravity is counted, and when no fall occurs, the center of gravity at each moment is linear in the activity area space. It should be explained that when the center of gravity floats within the set range, the float is not considered; and the swing trajectory of the limb points of the fall detection personnel when no fall occurs is collected in a reciprocating cycle and marked as a pendulum action;

[0055] The signal wave is used to identify the action of the fall detection personnel, and the instantaneous reduction speed peak value of the height of the center of gravity point of the fall detection personnel that changes in the straight line is collected. At the same time, the increase span value of the swing amplitude of the limb point after the corresponding limb point of the fall detection personnel changes the pendulum action is collected, and the instantaneous reduction speed peak value of the height of the center of gravity point of the fall detection personnel that changes in the straight line and the increase span value of the swing amplitude of the limb point after the corresponding limb point of the fall detection personnel changes the pendulum action are compared with the reduction speed peak threshold and the amplitude increase span threshold respectively:

[0056] If the instantaneous decreasing speed peak value of the height of the center of gravity point of the falling detection person's change line exceeds the decreasing speed peak threshold value, but the center of gravity point returns to the height of the line at the adjacent moment;

[0057] If the limb point of the fall detection person changes the pendulum motion at the corresponding limb point and exceeds the amplitude growth span threshold, but the swing amplitude of the corresponding pendulum motion at the adjacent moment drops to zero and then returns to the swing motion cycle;

[0058] When the above two situations occur at the same time, the real-time action state of the fall detection person is marked as a fall action and a stable balance state, and the action state is sent to the guardian;

[0059] If the instantaneous peak value of the speed reduction of the height of the center of gravity point where the fall detection person changes the straight line exceeds the peak value threshold of the speed reduction, and the center of gravity point has not recovered to the straight line height; if the increase span value of the swing amplitude of the limb point after the fall detection person changes the pendulum action of the corresponding limb point exceeds the amplitude increase span threshold, but the swing amplitude of the corresponding pendulum action at the adjacent moment drops to zero and has not recovered to the swing action cycle;

[0060] When any of the above two situations occurs, the real-time action status of the fall detection person is marked as a fall action and the balance state is not stabilized, and the action status is sent to the guardian;

[0061] If the instantaneous decreasing speed peak value of the height of the center of gravity point of the fall detection person's linear change does not exceed the decreasing speed peak threshold, and the increase span value of the swing amplitude of the limb point after the fall detection person's corresponding limb point changes the pendulum action exceeds the amplitude increase span threshold but does not exceed the amplitude increase span threshold, it is inferred that the real-time action state of the fall detection person is marked as no fall action, and the action state is sent to the guardian;

[0062] The guardian will give early warning to the fall detection personnel and provide timely assistance to the fall detection personnel;

[0063] The analysis process of falling action and spatial layout is as follows:

[0064] When a fall occurs and the person maintains balance, the overlapping time of the limb points of the fall detection person and the points of the set objects around the falling action location, as well as the time when the fall detection person maintains balance are collected, and the interval duration is obtained based on the time comparison, and is set as the object-assisted stabilization duration;

[0065] When a fall occurs and the balance is not maintained, the distance between the limbs of the fall detector and the set objects around the fall location is collected, and the distance between the limbs of the fall detector and the set objects around the fall location is marked as the object auxiliary distance value;

[0066] Analysis of object-assisted stabilization time and object-assisted interval distance:

[0067] If the auxiliary stabilization time of the object exceeds the stabilization time threshold, it is inferred that the auxiliary stabilization effect of the currently set object is low, and the currently set object position is marked as a low-effect object position;

[0068] If the auxiliary stabilization duration of the object does not exceed the stabilization duration threshold, it is inferred that the auxiliary stabilization effect of the currently set object is high, and the currently set object position is marked as a high-effect object position;

[0069] If the object auxiliary interval exceeds the set interval distance threshold, and the limb points of the fall detection person have a tendency to move toward the set object when the fall action occurs, it is inferred that the corresponding set object distance does not meet the auxiliary stability requirements, and the current set object position is marked as a long-distance object position;

[0070] If the object assistance interval does not exceed the set interval distance threshold, and the limb points of the fall detection person have a tendency to move toward the set object when the fall action occurs, it is inferred that the corresponding set object does not meet the assistance stability requirements, and the current set object position is marked as an inefficient assistance object position;

[0071] If the object assistance interval exceeds the set interval distance threshold, and the limb points of the fall detection personnel do not have a tendency to move toward the set object when the fall action occurs, the corresponding set object distance will be too far to assist in stabilization, and the current set object position will be marked as an unrelated object position;

[0072] If the object auxiliary interval does not exceed the set interval distance threshold, and the limb points of the fall detection person do not have a tendency to move toward the set object when the fall action occurs, the corresponding set object will not meet the auxiliary stability requirements, and the current set object position will be marked as an auxiliary invalid object position;

[0073] The falling action location of the real-time fall detection personnel and the high-action object location, low-action object location, long-distance object location, auxiliary inefficient object location, and auxiliary invalid object location are sent to the guardian terminal. After receiving the location, the guardian terminal re-layouts the activity area where the fall detection personnel are located, that is, the set objects are adjusted according to the set object position types corresponding to the surrounding areas of the falling action location. For example, at the high-action object location, the current set object is retained; at the low-action object location, the object type is replaced or auxiliary stable components, such as handles, are added; at the long-distance object location, the set object location is adjusted; at the auxiliary inefficient object location and the auxiliary invalid object location, the location is adjusted according to the actual layout, and components are added when adjustment is impossible;

[0074] When the present invention is in use, layout detection and marking are performed, and layout detection is performed on the activity area of ​​the fall detection personnel according to the millimeter wave radar technology, and the passage space in the activity area is obtained according to the layout detection; action recognition and warning, after determining the passage space, the behavior and action detection of the fall detection personnel is performed, and the real-time fall risk of the fall detection personnel is evaluated according to the behavior and action detection; spatial layout analysis is performed, and a set object at the position where the fall detection personnel has a fall action is obtained according to the spatial layout, and the person's body movements and the set object are connected and evaluated when the fall detection personnel has a fall action, and it is inferred whether the fall detection personnel needs to be balanced by the set object when falling.

[0075] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A fall detection method based on millimeter wave radar, characterized in that: The fall detection method process is as follows: Layout detection and annotation: Use millimeter-wave radar technology to perform layout detection on the activity area of ​​the fall detection personnel, and obtain the passage space within the activity area based on the layout detection; Motion recognition warning: after determining the passage space, the behavior and motion of the fall detection personnel are detected, and the real-time fall risk of the fall detection personnel is evaluated based on the behavior and motion detection; Spatial layout analysis: Based on the spatial layout, the set object at the position where the fall detection person falls is obtained. When the fall detection person falls, the person's body movements are connected and evaluated with the set object to infer whether the fall detection person needs to use the set object to maintain balance when falling.

2. The fall detection method based on millimeter wave radar according to claim 1, characterized in that: The process of layout detection and annotation is as follows: Set the signal wave emission point, expand the signal wave according to the millimeter wave radar to cover the activity area where the fall detection personnel are located, and determine the set objects in the activity area according to the continuous emission and reception of signal waves by the signal wave emission point, and obtain the shape information of each set object according to the change of the signal wave; after obtaining the shape information of each set object, obtain the space in the activity area except the space occupied by the set object, and mark it as the passage space; According to the continuity of the passage space, the movement trajectory space of the fall detection personnel in the passage space and the corresponding connected passage destination are obtained; The collected data include the ratio of the area of ​​the movement trajectory space of the fall detection personnel to the area of ​​the passage space, and the ratio of the movement trajectory distance in which the area of ​​the movement trajectory space of the fall detection personnel is greater than the area required for the fall detection personnel to move.

3. The fall detection method based on millimeter wave radar according to claim 2, characterized in that: If the area ratio of the moving trajectory space and the passing space exceeds the space area ratio threshold, or the proportion of the moving trajectory distance where the space area of ​​the falling detection personnel's moving trajectory is higher than the area required for the falling detection personnel to move does not exceed the moving trajectory distance ratio threshold, a high-risk signal is generated; if the area ratio of the moving trajectory space and the passing space does not exceed the space area ratio threshold, and the proportion of the moving trajectory distance where the space area of ​​the falling detection personnel's moving trajectory is higher than the area required for the falling detection personnel to move exceeds the moving trajectory distance ratio threshold, a low-risk signal is generated and sent to the guardian terminal.

4. The fall detection method based on millimeter wave radar according to claim 1, characterized in that: The process of motion recognition warning is as follows: The center point of the person is obtained according to the body shape of the fall detection person, and the center of gravity is marked to obtain the center of gravity point; the moving point is obtained according to the body shape and moving movements of the fall detection person, and it is marked as a limb point according to the moving point and the moving position of the fall detection person; the position of the center of gravity point is counted when the fall detection person moves, and the center of gravity point at each moment when no fall occurs is linear in the activity area space, and the flapping trajectory of the limb points of the fall detection person when no fall occurs is collected in a reciprocating cycle and marked as a pendulum movement.

5. The fall detection method based on millimeter wave radar according to claim 4, characterized in that: The signal wave is used to identify the actions of the fall detection personnel, and the instantaneous decrease speed peak value of the height of the center of gravity point of the fall detection personnel's change in the straight line and the increase span value of the swing amplitude of the limb point after the fall detection personnel's corresponding limb point changes the pendulum action are collected: If the instantaneous decrease speed peak value of the height of the center of gravity point of the fall detection personnel that changes the linear shape exceeds the decrease speed peak threshold, but the center of gravity point returns to the height of the linear shape at the adjacent moment; if the limb point of the fall detection personnel changes the pendulum motion at the corresponding limb point and exceeds the amplitude increase span threshold, but the swing amplitude of the corresponding pendulum motion at the adjacent moment drops to zero and then returns to the swing motion cycle; When the above two situations occur at the same time, the real-time action state of the fall detection person is marked as a fall action and a stable balance state, and the action state is sent to the guardian; If the instantaneous peak value of the speed reduction of the height of the center of gravity point where the fall detection person changes the straight line exceeds the peak value threshold of the speed reduction, and the center of gravity point has not recovered to the straight line height; if the increase span value of the swing amplitude of the limb point after the fall detection person changes the pendulum action of the corresponding limb point exceeds the amplitude increase span threshold, but the swing amplitude of the corresponding pendulum action at the adjacent moment drops to zero and has not recovered to the swing action cycle; When any of the above two situations occurs, the real-time action status of the fall detection person is marked as a fall and the balance state is not stabilized, and the action status is sent to the guardian.

6. The fall detection method based on millimeter wave radar according to claim 4, characterized in that: The process of spatial layout analysis is as follows: When a fall occurs and the person maintains balance, the overlapping time of the limb points of the fall detection person and the points of the set objects around the falling action location, as well as the time when the fall detection person maintains balance are collected, and the interval duration is obtained based on the time comparison, and is set as the object-assisted stabilization duration; When a person is falling and has not maintained his balance, the distance value between the limb points of the fall detection person and the set objects around the falling action location is collected, and the distance value between the limb points of the fall detection person and the set objects around the falling action location is marked as the object auxiliary distance value.

7. The fall detection method based on millimeter wave radar according to claim 6, characterized in that: Analysis of object-assisted stabilization time and object-assisted interval distance: If the object auxiliary stabilization time exceeds the stabilization time threshold, the currently set object position is marked as a low-action object position; If the object auxiliary stabilization time does not exceed the stabilization time threshold, the currently set object position is marked as a high-action object position; If the object auxiliary interval exceeds the set interval distance threshold, and the limb points of the fall detection person have a tendency to move toward the set object when the fall action occurs, the current set object position is marked as the long-distance object position; If the object assistance interval does not exceed the set interval distance threshold, and the limb points of the fall detection person have a tendency to move toward the set object when the fall action occurs, the current set object position is marked as an inefficient object position for assistance; If the object assistance interval exceeds the set interval distance threshold, and the limb points of the fall detection personnel do not have a tendency to move toward the set object when the fall action occurs, the corresponding set object distance will be too far to assist in stabilization, and the current set object position will be marked as an unrelated object position; If the object assistance interval does not exceed the set interval distance threshold, and the limb points of the fall detection person do not have a tendency to move toward the set object when a fall occurs, the corresponding set object will not meet the assistance stability requirements, and the current set object position will be marked as an invalid assistance object position.

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