An intelligent nursing system for bedridden old people and a self-adaptive compliant control method

Abstract

The present application belongs to the technical field of medical care, and particularly relates to an intelligent nursing system for bedridden old people and a self-adaptive compliant control method. The intelligent nursing system for bedridden old people comprises a multi-position nursing bed, a wheelchair mechanism for moving the old people, a moving and carrying device for carrying the old people from the multi-position nursing bed to the wheelchair mechanism; the wheelchair mechanism comprises an omnidirectional chassis, a folding chair plate assembly installed on the omnidirectional chassis, an adjusting mechanism, a containing cavity, a detection module and an autonomous positioning and navigation module. The detection module is used for positioning the relative position of the wheelchair mechanism and the closestool, the autonomous positioning and navigation module is used for receiving the detection data sent by the detection module, and the omnidirectional chassis is controlled to adjust the position and pose and dock with the closestool according to the received detection data, so as to combine the real-time monitoring of the wheelchair mechanism with the autonomous positioning and navigation, and realize the self-adaptive compliant control of the wheelchair-closestool.

Description

Technical Field

[0001] This invention belongs to the field of medical and nursing technology, specifically relating to an intelligent nursing system for bedridden elderly people and an adaptive compliant control method. Background Technology

[0002] In recent years, intelligent care for bedridden elderly people has attracted much attention. For example, the air cushion turning and nursing bed designed by YMM in South Korea, the nursing wheelchair conversion bed designed by Panasonic in Japan, and the dual-arm nursing robot designed by Fudan University are all special designs to facilitate daily care for bedridden elderly people, such as turning over, moving, and using the toilet.

[0003] However, most current smart nursing devices are based on the realization of one function. Multiple nursing devices are independent of each other. Due to the structural limitations of their design, each independent device cannot simultaneously and systematically realize functions such as turning over, transferring, toileting, and bathing for bedridden elderly people. Moreover, toileting for the elderly requires manual pushing or placing the bedpan on a wheelchair, which brings a bad experience to the elderly or caregivers. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of existing technologies that cannot systematically realize multiple functions such as transportation, toileting, and bathing for bedridden elderly people, and cannot automatically and smoothly move wheelchairs, and to provide an intelligent nursing system for bedridden elderly people and an adaptive and smooth control method.

[0005] The technical solution adopted by this invention to solve its technical problem is:

[0006] As a first aspect, an intelligent nursing system for bedridden elderly includes a multi-position nursing bed, a wheelchair mechanism for moving the elderly, and a transfer and transport device for moving the elderly from the multi-position nursing bed to the wheelchair mechanism.

[0007] The wheelchair mechanism includes:

[0008] An omnidirectional chassis and a folding chair panel assembly mounted on the omnidirectional chassis;

[0009] An adjustment mechanism is installed on the omnidirectional chassis at one end and connected to the folding chair panel assembly at the other end, used to change the folding or unfolding state of the folding chair panel assembly;

[0010] A receiving cavity, located at the rear end of the chassis, is used for the toilet to enter and exit;

[0011] A detection module, installed on the omnidirectional chassis, is used to locate the relative positions of the wheelchair mechanism and the corresponding toilet.

[0012] The autonomous positioning and navigation module is used to receive the detection data sent by the detection module, and control the omnidirectional chassis to perform posture adjustment and toilet docking actions based on the received detection data.

[0013] Furthermore, the folding chair assembly includes a backrest frame, a hip frame, a leg frame, and a footrest frame that are rotatably connected in sequence; and a backrest, hip, push plate, and footrest that are correspondingly installed on the backrest frame, hip frame, leg frame, and footrest frame.

[0014] The adjustment mechanism includes:

[0015] An adjusting cylinder is provided, with its fixed end mounted on the back plate and its telescopic end rotatably connected to the omnidirectional chassis.

[0016] Two adjustment plates are symmetrically arranged on both sides of the omnidirectional chassis; one end of each adjustment plate is rotatably connected to the hip plate frame, and the other end is rotatably connected to the foot pedal frame.

[0017] A protective cover is fitted over the adjusting cylinder to prevent bath water from entering the adjusting cylinder.

[0018] Furthermore, when the adjusting cylinder is in the extended state, the folding chair assembly is in a reclining state; when the adjusting cylinder is in the retracted state, the folding chair assembly is in a sitting posture.

[0019] Furthermore, the wheelchair mechanism also includes a toilet opening and closing mechanism mounted on the omnidirectional chassis; the toilet opening and closing mechanism includes a first opening and closing cylinder and a second opening and closing cylinder disposed along the Y-axis at the front end of the omnidirectional chassis; a second opening and closing plate and a first opening and closing plate respectively connected to the telescopic ends of the first opening and closing cylinder and the second opening and closing cylinder;

[0020] The first and second opening and closing cylinders respectively drive the second and first opening and closing plates to move along the Y-axis direction through the guide rail slider assembly set on the hip plate frame.

[0021] Furthermore, the first and second opening and closing plates are semi-circular structures that cooperate with each other, and are both set on the through hole in the middle of the butt plate;

[0022] When both the first and second opening and closing cylinders are in the initial state, the mating surfaces of the first and second opening and closing plates are tightly fitted; when the first and second opening and closing cylinders are in the extended state, a space for the elderly to use the toilet is provided between the mating surfaces of the first and second opening and closing plates.

[0023] Furthermore, sealing plates are provided on both sides and the front end of the omnidirectional chassis.

[0024] Secondly, based on the aforementioned adaptive compliant control method for an intelligent nursing system for bedridden elderly, the following steps are included:

[0025] S1. Construct a "wheelchair-toilet" motion model; set the wheelchair coordinates with the center of the receiving cavity as the coordinate origin; set the toilet coordinates with the center of the toilet as the coordinate origin, and calculate the mapping equation between the two coordinates;

[0026] S2. An autonomous positioning and navigation module is used to perform coarse positioning of the wheelchair mechanism and toilet; that is, the receiving cavity is set in the Y... L The diameter in the direction is larger than that of the toilet in the Y direction. C The diameter in the direction is used to move the wheelchair mechanism to the position in front of the toilet in the receiving cavity.

[0027] S3. Posture recognition, which means that the autonomous positioning and navigation module performs posture recognition on the wheelchair mechanism based on the position and angle information of the wheelchair mechanism and toilet detected by the detection module.

[0028] S4. Calculate the contact force between the wheelchair mechanism and the toilet; that is, calculate the contact force based on the posture of the wheelchair mechanism and the position of the toilet.

[0029] S5. The position and posture adjustment of the wheelchair mechanism, that is, the autonomous positioning and navigation module controls the wheelchair mechanism to adjust to the position of the receiving cavity facing the front of the toilet based on the wheelchair posture mechanism and toilet position information determined in step S3, and the docking contact force calculated in step S4.

[0030] S6. Automatic docking of the wheelchair mechanism with the toilet, i.e., smooth docking of the movable wheelchair mechanism with the toilet;

[0031] S7. Activate the toilet opening and closing mechanism. After the elderly person finishes using the toilet, close the toilet opening and closing mechanism and move the wheelchair mechanism.

[0032] Furthermore, the autonomous positioning and navigation module includes a signal receiving module for receiving data sent by the detection module, a calculation module for calculating the wheelchair posture and docking contact force, a lidar SLAM, and an adaptive compliant controller for controlling the movement of the wheelchair mechanism.

[0033] The calculation module uses the Kalman filter algorithm to calculate the wheelchair pose and docking contact force, specifically including the following calculations:

[0034] Calculation using a priori formulas: ;

[0035] Calculation of prior error covariance using the formula: ;

[0036] Kalman gain calculation formula: ;

[0037] Error covariance formula calculation: ;

[0038] The final estimation formula is calculated as follows: ;

[0039] In the formula, True value, Kalman estimate Kalman estimation error covariance matrix For predicted values, For the prediction error covariance matrix, Let A be the Kalman gain, and A be the state transition matrix. Let B be the system input, and let B be the input gain matrix. H represents process noise, and H is the measurement matrix.

[0040] The calculation module uses the Kalman filter algorithm to calculate the wheelchair posture and docking contact force.

[0041] Furthermore, the detection module includes a distance sensor and a force tactile sensor.

[0042] Furthermore, the wheelchair mechanism is equipped with an obstacle avoidance module during movement. This module includes a lidar and ultrasonic probe installed within the wheelchair mechanism's movement space, as well as an obstacle avoidance controller. The obstacle avoidance controller employs a multi-sensor information fusion algorithm and an improved... The algorithm plans the path.

[0043] The beneficial effects of the intelligent nursing system for bedridden elderly and the adaptive compliant control method of the present invention are:

[0044] The omnidirectional chassis of the wheelchair mechanism of the present invention has a receiving cavity at the rear end for the toilet to enter and exit. A detection module is used to locate the relative position of the wheelchair mechanism and the toilet. An autonomous positioning and navigation module is used to receive the detection data sent by the detection module and control the omnidirectional chassis to adjust its posture and dock with the toilet according to the received detection data. By combining real-time monitoring of the wheelchair mechanism with autonomous positioning and navigation, adaptive and compliant control of the "wheelchair-toilet" is achieved.

[0045] This invention establishes a multi-functional nursing system for bedridden elderly people, including turning over, transferring, toileting, and bathing. It is equipped with a transfer device for transferring between multi-position nursing beds and wheelchairs, and uses a detection module to dynamically adjust the position of the wheelchair mechanism to achieve smooth docking and safe transfer between the wheelchair mechanism and the nursing bed. Attached Figure Description

[0046] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0047] Figure 1 This is an overall flowchart of the intelligent nursing system for bedridden elderly according to an embodiment of the present invention.

[0048] Figure 2 This is a first-view perspective perspective view of the wheelchair mechanism according to an embodiment of the present invention.

[0049] Figure 3 This is a second-view perspective perspective view of the wheelchair mechanism according to an embodiment of the present invention.

[0050] Figure 4 This is a partial structural schematic diagram of the wheelchair mechanism according to an embodiment of the present invention.

[0051] Figure 5 This is a schematic diagram of the toilet opening and closing mechanism according to an embodiment of the present invention.

[0052] Figure 6 This is a simplified adjustment diagram of the folding chair panel assembly and adjustment mechanism according to an embodiment of the present invention.

[0053] Figure 7 This is a control flowchart of the intelligent nursing system for bedridden elderly according to an embodiment of the present invention.

[0054] Figure 8 This is a diagram illustrating the docking process between the wheelchair mechanism and the toilet according to an embodiment of the present invention.

[0055] Figure 9 This is a diagram showing the movement of the wheelchair mechanism according to an embodiment of the present invention.

[0056] Figure 10 This is a flowchart of the obstacle avoidance module in an embodiment of the present invention.

[0057] Figure 11 This is a flowchart of the grid map construction process according to an embodiment of the present invention.

[0058] In the diagram: 1. Multi-position nursing bed; 2. Wheelchair mechanism; 21. Omnidirectional chassis; 22. Folding chair assembly; 221. Backrest frame; 222. Hiprest frame; 223. Legrest frame; 224. Footrest frame; 23. Adjustment mechanism; 231. Adjustment cylinder; 232. Adjustment plate; 233. Protective cover; 24. Receiving cavity; 25. Detection module; 26. Autonomous positioning and navigation module; 27. Toilet opening and closing mechanism; 271. First opening and closing cylinder; 272. Second opening and closing cylinder; 273. Guide rail slider assembly; 274. First opening and closing plate; 275. Second opening and closing plate; 28. Sealing plate; 3. Transfer and transport device; 4. Toilet. Detailed Implementation

[0059] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention, and therefore only show the components relevant to the invention.

[0060] like Figures 1-6 The embodiment of the intelligent nursing system for bedridden elderly shown in this invention includes a multi-position nursing bed 1, a wheelchair mechanism 2 for moving the elderly, and a transfer device 3 for moving the elderly from the multi-position nursing bed 1 to the wheelchair mechanism 2. The wheelchair mechanism 2 includes: an omnidirectional chassis 21 and a folding chair assembly 22 mounted on the omnidirectional chassis 21; an adjustment mechanism 23, one end mounted on the omnidirectional chassis 21 and the other end connected to the folding chair assembly 22, for changing the folding or unfolding state of the folding chair assembly 22; a receiving cavity 24 located at the rear end of the chassis for the entry and exit of a toilet 4; a detection module 25 mounted on the omnidirectional chassis 21 for positioning the relative positions of the wheelchair mechanism 2 and the corresponding toilet 4; and an autonomous positioning and navigation module 26 for receiving detection data sent by the detection module 25 and controlling the omnidirectional chassis 21 to adjust its posture and the docking action of the toilet 4 based on the received detection data.

[0061] The omnidirectional chassis 21 of the wheelchair mechanism 2 of the present invention has a receiving cavity 24 for the toilet 4 to enter and exit at its rear end. A detection module 25 is used to locate the relative position of the wheelchair mechanism 2 and the toilet 4. An autonomous positioning and navigation module 26 is used to receive the detection data sent by the detection module 25 and control the omnidirectional chassis 21 to adjust its posture and dock with the toilet 4 according to the received detection data. By combining the real-time monitoring of the wheelchair mechanism 2 with autonomous positioning and navigation, adaptive and compliant control of the "wheelchair-toilet 4" is achieved.

[0062] It should be noted that the multi-position nursing bed 1 and the transfer device 3 used in this embodiment are structures that can be adapted and designed by those skilled in the art. The multi-position nursing bed 1 enables flexible turning of bedridden elderly people, and the transfer device 3 enables bidirectional transport between the multi-position nursing bed 1 and the wheelchair mechanism 2 for bedridden elderly people. The specific structures of the multi-position nursing bed 1 and the transfer device 3 will not be described in detail here. During the transfer process, based on the motion constraint relationship between the nursing bed, the transfer device, and the wheelchair mechanism 2, the bed-chair mechanism is smoothly connected and safely transported. It should be understood that the main design point of the intelligent nursing system in this embodiment lies in the design of the wheelchair mechanism 2 and the integration of multiple modules. The specific structures of the multi-position nursing bed 1 and the transfer device 3 are not described in detail and will not have a clear impact on the functional realization of the present invention.

[0063] like Figure 2 and Figure 6As shown, in this embodiment, the folding chair panel assembly 22 includes a backrest frame 221, a hip frame 222, a leg frame 223, and a footrest frame 224 that are rotatably connected in sequence; and a backrest, hip, push plate, and footrest that are correspondingly installed on the backrest frame 221, hip frame 222, leg frame 223, and footrest frame 224.

[0064] like Figure 3 and Figure 4 As shown, the adjustment mechanism 23 includes an adjustment cylinder 231, two adjustment plates 232, and a protective cover 233 mounted on the adjustment cylinder. The fixed end of the adjustment cylinder 231 is mounted on the back plate, and the telescopic end of the adjustment cylinder 231 is rotatably connected to the omnidirectional chassis 21. The two adjustment plates 232 are symmetrically arranged on both sides of the omnidirectional chassis 21. One end of the adjustment plate 232 is rotatably connected to the buttock frame 222, and the other end is rotatably connected to the foot pedal frame 224. The protective cover 233 is fitted over the adjustment cylinder 231 to prevent bathing water from entering the interior of the adjustment cylinder 231.

[0065] In use, when the adjusting cylinder 231 is extended, the folding chair assembly 22 is in a reclining position; when the adjusting cylinder 231 is retracted, the folding chair assembly 22 is in a sitting position. Furthermore, to ensure the airtightness of the entire wheelchair mechanism 2, sealing plates 28 are provided on both sides and the front face of the omnidirectional chassis 21. In this embodiment, the power components in the folding chair assembly 22 adopt a sealed design, optimizing material selection and manufacturing assembly processes to achieve the wheelchair's waterproof function, thus enabling the elderly to bathe whether in a sitting or reclining position.

[0066] like Figure 5 As shown, to facilitate the elderly's toileting actions, the wheelchair mechanism 2 in this embodiment also includes a toilet opening and closing mechanism 27 installed on the omnidirectional chassis 21. The toilet opening and closing mechanism 27 includes a first opening and closing cylinder 271 and a second opening and closing cylinder 272 arranged along the Y-axis direction at the front end of the omnidirectional chassis 21. A second opening and closing plate 275 and a first opening and closing plate 274 are respectively connected to the telescopic ends of the first opening and closing cylinder 271 and the second opening and closing cylinder 272. The first opening and closing cylinder 271 and the second opening and closing cylinder 272 respectively drive the second opening and closing plate 275 and the first opening and closing plate 274 to move along the Y-axis direction through the guide rail slider assembly 273 arranged on the hip board frame 222. The first opening and closing plate 274 and the second opening and closing plate 275 are semi-circular structures that cooperate with each other. They are both set on the through hole in the middle of the buttock plate. When the first opening and closing cylinder 271 and the second opening and closing cylinder 272 are in the initial state, the mating surfaces of the first opening and closing plate 274 and the second opening and closing plate 275 are tightly fitted. When the first opening and closing cylinder 271 and the second opening and closing cylinder 272 are in the extended state, a space for the elderly to use the toilet is set between the mating surfaces of the first opening and closing plate 274 and the second opening and closing plate 275.

[0067] This invention establishes a multi-functional nursing system for bedridden elderly people, including turning over, transferring, using the toilet, and bathing. It is equipped with a transfer device 3 for transferring between a multi-position nursing bed 1 and a wheelchair mechanism 2, and uses a detection module 25 to dynamically adjust the position of the wheelchair mechanism 2 to achieve smooth docking and safe transfer between the wheelchair mechanism 2 and the nursing bed.

[0068] The adaptive compliant control method based on the above-mentioned intelligent nursing system for bedridden elderly includes the following steps:

[0069] S1. Construct a motion model of the "wheelchair-toilet 4"; set the wheelchair coordinate X with the center of the receiving cavity 24 as the origin. L O L ,Y L With the center of toilet 4 as the origin, set the X-axis coordinate of toilet 4. C O C ,Y C Calculate the mapping relationship between the two coordinates;

[0070] S2. The autonomous positioning and navigation module 26 is used to perform coarse positioning of the wheelchair mechanism 2 and the toilet 4; that is, the receiving cavity 24 is set in the Y... L The diameter in the direction is greater than that of the toilet in the Y direction. C The diameter in the direction moves the wheelchair mechanism 2 to the position in front of the toilet 4 in the receiving cavity 24;

[0071] S3. Posture recognition, that is, the autonomous positioning and navigation module 26 performs posture recognition on the wheelchair mechanism 2 based on the position and angle information of the wheelchair mechanism 2 and the toilet 4 detected by the detection module 25.

[0072] S4. Calculate the contact force between the wheelchair mechanism 2 and the toilet 4; that is, calculate the contact force based on the posture of the wheelchair mechanism 2 and the position of the toilet 4.

[0073] S5. The position and posture adjustment of the wheelchair mechanism 2, that is, the autonomous positioning and navigation module 26 controls the wheelchair mechanism 2 to adjust to the position of the receiving cavity 24 facing the front of the toilet 4 according to the wheelchair posture mechanism and toilet 4 position information determined in step S3, and the docking contact force calculated in step S4.

[0074] S6. Automatic docking of wheelchair mechanism 2 and toilet 4, through environmental impedance model, i.e., smooth docking of the moving wheelchair mechanism 2 and toilet 4.

[0075] S7. Activate the toilet opening and closing mechanism 27. After the elderly person finishes using the toilet, close the toilet opening and closing mechanism 27 and move the wheelchair mechanism 2.

[0076] The autonomous positioning and navigation module 26 in this embodiment includes a signal receiving module for receiving data sent by the detection module 25, a calculation module for calculating the wheelchair posture and docking contact force, a lidar SLAM, and an adaptive compliant controller for controlling the movement of the wheelchair mechanism 2. The calculation module uses a Kalman filter algorithm to calculate the wheelchair posture and docking contact force. The detection module 25 includes a distance sensor and a force tactile sensor.

[0077] The calculation process of the Kalman filter algorithm in this embodiment is as follows:

[0078] Calculation using a priori formulas: ;

[0079] Calculation of prior error covariance using the formula: ;

[0080] Kalman gain calculation formula: ;

[0081] Error covariance formula calculation: ;

[0082] The final estimation formula is: ;

[0083] In the formula, True value, Kalman estimate Kalman estimation error covariance matrix For predicted values, For the prediction error covariance matrix, Let A be the Kalman gain, and A be the state transition matrix. Let B be the system input, and let B be the input gain matrix. H represents process noise, and H is the measurement matrix.

[0084] This embodiment calculates attitude and contact stress based on the data measured by the aforementioned sensors using an algorithmic integration method. Using a Kalman filter algorithm provides a better filtering effect, quickly extracting results from complex data, resulting in a smoother data curve and improving the accuracy of contact force calculation. Therefore, this method is adopted in this example.

[0085] like Figure 7 and Figure 8As shown, the control process of the autonomous positioning and guidance module is as follows: Based on the data collected by multiple distance sensors and force tactile sensors in step S1, the mapping relationship between the toilet 4 and the wheelchair mechanism 2 is calculated. The relative positions (δ, s, θ) of the wheelchair mechanism 2 and the toilet 4 are set according to the docking area position. The relative position data is transmitted to the adaptive compliant controller in the autonomous positioning and navigation module 26. The adaptive compliant controller controls the movement of the omnidirectional chassis 21 in the wheelchair mechanism 2 for coarse positioning. The data information of the movement of the omnidirectional chassis 21 is transmitted to the environmental impedance calculation module. The environmental impedance calculation module uses the contact force F calculated in step S1 to perform impedance control on the position of the wheelchair mechanism 2 for attitude adjustment and fine positioning. The wheelchair-toilet 4 achieves a three-level automatic docking mode of coarse positioning, attitude recognition and adjustment, and fine positioning, thus realizing the compliant docking of the wheelchair and toilet 4.

[0086] The wheelchair mechanism 2 is also equipped with an obstacle avoidance module during its movement. This module includes a lidar and ultrasonic probe installed within the movement space of the wheelchair mechanism 2; and an obstacle avoidance controller, which employs a multi-sensor information fusion algorithm and an improved... The algorithm plans the path. In this embodiment, a wheelchair sensing and monitoring system is built, and obstacle avoidance strategies and path planning based on multi-sensor information fusion are used to achieve safe walking of wheelchairs in dynamic indoor environments.

[0087] The improved heuristic function in this embodiment The calculation is as follows:

[0088] Set points in the grid The target point is A commonly used heuristic is Euclidean distance:

[0089] ;

[0090] Cost function in this embodiment The calculation is as follows:

[0091] Whenever we move from the starting point to a new node via a path The movement cost to reach that node will be added up. For example, if the movement cost per step is 1, then:

[0092]

[0093] Overall evaluation function The calculation is as follows:

[0094] Combining the two values ​​above, we obtain To evaluate the total cost of nodes, in order to determine which nodes should be prioritized:

[0095] ;

[0096] in, The heuristic function of the algorithm is expressed as: f(n) is the value obtained from the initial state through the state. The cost estimate to reach the target state, g(n), is the cost in the state space from the initial state to the target state. The actual cost, From state The estimated cost of the optimal path to the target state.

[0097] It should be understood that for pathfinding problems, the states are the nodes in the graph, and the cost is the distance. The Astar algorithm is a heuristic search algorithm. Heuristic search evaluates each search position in the state space, obtains the best position, and then searches from that position until the target is reached. This can eliminate a large number of unnecessary search paths, improving efficiency. In heuristic search, the evaluation of positions is crucial. Different evaluations can yield different results.

[0098] Specifically, such as Figure 11 As shown, the obstacle avoidance module's grid map construction process includes the following steps:

[0099] A1. Conduct preliminary measurements of the overall interior dimensions;

[0100] A2. Establish the indoor obstacle avoidance coordinate system and determine the wheelchair position;

[0101] A3. Normalize the measurement data from step A1 with the obstacle avoidance coordinate system from step A2;

[0102] A4. Set the grid map size and grid division to initialize the overall obstacle avoidance controller settings;

[0103] A5. Calculate obstacle locations and update raster map data;

[0104] A6. Calculate whether the safe distance is exceeded. If the safe distance is exceeded, expand the grid. If the safe distance is not exceeded, determine whether the mapping is finished. If the mapping process is finished, end the grid map mapping. If the mapping process is not finished, continue to transmit wheelchair pose data and obstacle distance data, and update the grid map.

[0105] It should be understood that the specific embodiments described above are for illustrative purposes only and are not intended to limit the scope of the invention. Obvious variations or modifications derived from the spirit of the invention are still within the protection scope of the invention.

Claims

1. An adaptive compliant control method for an intelligent nursing system for bedridden elderly people, characterized in that: The intelligent nursing system for bedridden elderly includes a multi-position nursing bed (1), a wheelchair mechanism (2) for moving the elderly, and a transfer device (3) for moving the elderly from the multi-position nursing bed (1) to the wheelchair mechanism (2). The wheelchair mechanism (2) includes: An omnidirectional chassis (21) and a folding chair panel assembly (22) mounted on the omnidirectional chassis (21); The adjustment mechanism (23) is mounted on the omnidirectional chassis (21) at one end and connected to the folding chair panel assembly (22) at the other end, and is used to change the folding or unfolding state of the folding chair panel assembly (22); A receiving cavity (24) is provided at the rear end of the chassis for the toilet (4) to enter and exit; The detection module (25) is installed on the omnidirectional chassis (21) and is used to locate the relative position of the wheelchair mechanism (2) and the corresponding toilet (4); the detection module (25) includes a distance sensor and a force tactile sensor; The autonomous positioning and navigation module (26) is used to receive the detection data sent by the detection module (25) and control the omnidirectional chassis (21) to perform posture adjustment and docking action of the toilet (4) according to the received detection data; The adaptive compliant control method of the intelligent nursing system for bedridden elderly includes the following steps: S1. Construct a motion model of "wheelchair-toilet (4)"; with the center position of the receiving cavity (24) as the origin of the coordinate system, set the wheelchair coordinate (X) L O L ,Y L ); with the center of the toilet (4) as the origin, set the coordinates (X) of the toilet (4). C O C ,Y C ), calculate the mapping relationship between the two coordinates; S2. The autonomous positioning and navigation module (26) is used to perform coarse positioning of the wheelchair mechanism (2) and the toilet (4); that is, the receiving cavity (24) is set in the Y direction. L The diameter in the direction is greater than that of the toilet (4) in the Y direction. C The diameter in the direction is used to move the wheelchair mechanism (2) to the position of the receiving cavity (24) in front of the toilet (4); S3. Posture recognition, that is, the autonomous positioning and navigation module (26) performs posture recognition on the wheelchair mechanism (2) based on the position and angle information of the wheelchair mechanism (2) and the toilet (4) detected by the detection module (25); S4. Calculate the contact force between the wheelchair mechanism (2) and the toilet (4); that is, calculate the contact force based on the posture of the wheelchair mechanism (2) and the position of the toilet (4); the contact force is calculated using the Kalman filter algorithm based on the data from the distance sensor and the force sensor. S5. The position adjustment of the wheelchair mechanism (2) is that the autonomous positioning and navigation module (26) controls the wheelchair mechanism (2) to be adjusted to the front of the toilet (4) based on the wheelchair posture mechanism and toilet (4) position information determined in step S3 and the docking contact force calculated in step S4. S6. Automatic docking of wheelchair mechanism (2) and toilet (4), i.e., smooth docking of the movable wheelchair mechanism (2) and toilet (4); S7. Activate the toilet opening and closing mechanism (27). After the elderly person finishes using the toilet, close the toilet opening and closing mechanism (27) and move the wheelchair mechanism (2).

2. The adaptive compliant control method for an intelligent nursing system for bedridden elderly people according to claim 1, characterized in that: The autonomous positioning and navigation module (26) includes a signal receiving module for receiving data sent by the detection module (25), a calculation module for calculating the wheelchair posture and docking contact force, a lidar SLAM, and an adaptive compliant controller for controlling the movement of the wheelchair mechanism (2). In step S1, the data collected by multiple distance sensors and force tactile sensors are used to calculate the mapping relationship between the toilet (4) and the wheelchair mechanism (2). The relative positions (δ, s, θ) of the wheelchair mechanism (2) and the toilet (4) are set according to the docking area position. The relative position data is transmitted to the adaptive compliant controller. The adaptive compliant controller controls the movement of the omnidirectional chassis (21) in the wheelchair mechanism (2) for coarse positioning. The data information of the movement of the omnidirectional chassis (21) is transmitted to the environmental impedance calculation module. The environmental impedance calculation module adjusts the position of the wheelchair mechanism (2) by impedance control based on the contact force F calculated in step S4 for fine positioning.

3. The adaptive compliant control method for an intelligent nursing system for bedridden elderly people according to claim 2, characterized in that: The calculation module uses the Kalman filter algorithm to calculate the wheelchair posture and docking contact force.

4. The adaptive compliant control method for an intelligent nursing system for bedridden elderly people according to claim 1, characterized in that: The folding chair assembly (22) includes a backrest frame (221), a hip frame (222), a leg frame (223), and a footrest frame (224) that are rotatably connected in sequence; and a backrest, hip, leg and footrest that are respectively installed on the backrest frame (221), hip frame (222), leg frame (223) and footrest frame (224); The adjustment mechanism (23) includes: An adjusting cylinder (231) is installed on the back plate, and the telescopic end of the adjusting cylinder (231) is rotatably connected to the omnidirectional chassis (21). Two adjustment plates (232) are symmetrically arranged on both sides of the omnidirectional chassis (21); one end of the adjustment plate (232) is rotatably connected to the hip board frame (222), and the other end is rotatably connected to the foot pedal frame (224); A protective cover (233) is fitted over the adjusting cylinder (231) to prevent bath water from entering the adjusting cylinder (231).

5. The adaptive compliant control method for an intelligent nursing system for bedridden elderly people according to claim 4, characterized in that: When the adjusting cylinder (231) is in the extended state, the folding chair assembly (22) is in the reclining state; when the adjusting cylinder (231) is in the retracted state, the folding chair assembly (22) is in the sitting position.

6. The adaptive compliant control method for an intelligent nursing system for bedridden elderly people according to claim 4, characterized in that: The wheelchair mechanism (2) also includes a toilet opening and closing mechanism (27) mounted on the omnidirectional chassis (21); the toilet opening and closing mechanism (27) includes a first opening and closing cylinder (271) and a second opening and closing cylinder (272) arranged along the Y-axis at the front end of the omnidirectional chassis (21); and a second opening and closing plate (275) and a first opening and closing plate (274) respectively connected to the telescopic ends of the first opening and closing cylinder (271) and the second opening and closing cylinder (272); The first opening and closing cylinder (271) and the second opening and closing cylinder (272) respectively drive the second opening and closing plate (275) and the first opening and closing plate (274) to move along the Y-axis direction through the guide rail slider assembly (273) set on the hip plate frame (222).

7. The adaptive compliant control method for an intelligent nursing system for bedridden elderly people according to claim 6, characterized in that: The first opening and closing plate (274) and the second opening and closing plate (275) are semi-circular structures that cooperate with each other, and are both set on the through hole in the middle of the butt plate; When the first opening and closing cylinder (271) and the second opening and closing cylinder (272) are both in the initial state, the mating surfaces of the first opening and closing plate (274) and the second opening and closing plate (275) are tightly fitted; when the first opening and closing cylinder (271) and the second opening and closing cylinder (272) are in the extended state, a space for the elderly to use the toilet is provided between the mating surfaces of the first opening and closing plate (274) and the second opening and closing plate (275).

8. The adaptive compliant control method for an intelligent nursing system for bedridden elderly according to claim 1, characterized in that: Sealing plates (28) are provided on both sides and the front end of the omnidirectional chassis (21).

9. The adaptive compliant control method for an intelligent nursing system for bedridden elderly people according to claim 7, characterized in that: The wheelchair mechanism (2) is also equipped with an obstacle avoidance module during movement. The obstacle avoidance module includes a lidar and an ultrasonic probe installed in the movement space of the wheelchair mechanism (2); and an obstacle avoidance controller. The obstacle avoidance controller adopts a multi-sensor information fusion algorithm and an improved... The algorithm plans the path; The improvement The algorithm is represented as: f(n) is the value obtained from the initial state through the state. The cost estimate to reach the target state, g(n), is the cost in the state space from the initial state to the target state. The actual cost, From state The estimated cost of the optimal path to the target state.

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