Control system and method of nursing wheelchair with autonomous docking function

Abstract

The invention relates to a control system and method for a nursing wheelchair with an autonomous docking function. The control system comprises a control mode recognition module, a driving control module, a posture adjustment module, a docking recognition module, a transfer execution module and a system scheduling module. The system runs based on an embedded real-time operating system, has task concurrent scheduling and data closed-loop control capabilities, and can realize control processes such as path navigation, autonomous docking, posture linkage and stable transfer of the wheelchair in different nursing scenes; autonomous navigation, accurate docking and barrier-free transfer of various nursing platforms such as a nursing bed, a bathing cabin and a defecation device can be realized, manual intervention is remarkably reduced, the labor intensity of nursing personnel is reduced, the nursing efficiency and the use comfort of long-term bedridden patients are improved, the operation burden of the nursing personnel is effectively reduced, and the working efficiency of the nursing personnel is improved. The purpose of efficient, convenient and low-intervention nursing of long-term bedridden patients is achieved, and the rehabilitation nursing effect and the use experience of the patients are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of medical rehabilitation equipment control, in particular to a nursing wheelchair control method with autonomous navigation, precise docking and posture adjustment functions for long-term bedridden patients, and specifically to a wheelchair control system and method for realizing multi-scene automatic docking and flexible transfer. BACKGROUND

[0002] Most of the current market nursing wheelchairs have single functions and lack complete nursing process support capabilities. Patients still need the assistance of nursing staff during processes such as toilet, bathing, and bed-chair transfer. Although some electric wheelchairs have driving and posture adjustment functions, they still lack in environmental perception, autonomous navigation, and automatic docking, resulting in inconvenient transfer process, high safety risk, and heavy dependence on patients, which makes it difficult to meet the urgent needs of intelligent and barrier-free nursing. How to realize the autonomous positioning, path planning, device docking, and body transfer control of the wheelchair has become an important topic for improving the nursing level of disabled people.

[0003] In existing related patent technologies, such as patent CN120549709B, the bed-chair conversion, toilet, and turning over functions are coordinated by a central control unit, but the docking process relies on a pre-set "accommodation space" and cannot handle the re-docking problem after the nursing bed position changes. Patent CN120478071A uses two-dimensional code to identify the bed position, but once the identification is blocked or contaminated, the entire positioning process will fail. In addition, existing technologies generally lack real-time verification of the state of the target device, and the navigation strategy is single, making it difficult to adapt to multiple nursing scenarios.

[0004] Therefore, there is an urgent need for a nursing wheelchair docking and transfer control system and method that can overcome the above-mentioned defects and realize truly autonomous, safe, and universal nursing wheelchair docking and transfer control. SUMMARY

[0005] To solve the problems of single function, insufficient autonomy, and manual operation for device docking between existing nursing wheelchairs, the present application aims to provide a multifunctional nursing wheelchair autonomous docking and transfer control system and method for long-term bedridden patients. The system can realize autonomous navigation, precise docking, posture adjustment, and flexible transfer of the wheelchair in nursing scenarios without human intervention, significantly improving the autonomous nursing ability and quality of life of bedridden patients, reducing the labor intensity of nursing staff, and improving overall care efficiency.

[0006] To achieve the above-mentioned purpose, the present application proposes the following technical solutions: A control system for a nursing wheelchair with autonomous docking function, comprising: a control mode recognition module, a driving control module, a posture adjustment module, a docking recognition module, a transfer execution module, and a system scheduling module. The control mode recognition module is configured to recognize a current running task state of the wheelchair and switch a control flow and a control mode, and the control mode includes a driving mode and a posture transformation mode. The driving control module is configured to implement a manual driving mode and an automatic driving mode, and the manual driving mode and the automatic driving mode are switched through voice recognition or a wireless remote controller input instruction; the automatic driving mode includes radar navigation and infrared tracking navigation. The posture adjustment module includes a plurality of linkage push rod structures and a limit detection device, and is configured to adjust an angle of a backrest and a leg support of the wheelchair through an electric push rod; and supports adaptive position fine adjustment to adapt to a geometric structure of a target nursing device and to prepare for patient transfer. The docking recognition module includes a magnetic induction device, an infrared sensor array, a reed tube triggering device and a contact switch, and is configured to determine whether the wheelchair and the target nursing device are accurately docked. The transfer execution module adopts a flexible conveying structure, and includes a roller motor, a synchronous driving device and a flexible conveying belt, and is configured to realize patient sliding transfer. The system scheduling module runs on an embedded real-time operating system, and is configured to implement multi-task concurrent scheduling and inter-module coordination.

[0007] Further, in the manual driving sub-mode, the wearer uses a joystick or a remote controller to control the driving direction and speed of the wheelchair in real time, and forward movement, backward movement and turning are realized through a differential driving mode; in the automatic driving mode, radar navigation or tracking navigation is selected according to a navigation recognition result to realize path guidance: the radar navigation is based on an upper computer path planning system, and laser radar and IMU are fused to realize indoor environment mapping, positioning and path generation; the tracking navigation is based on an infrared tracking sensor array installed at the bottom of the wheelchair, and ground guide line deviation information is recognized, and a fuzzy PID control strategy is combined to adjust the speed difference of the driving wheels to realize path tracking.

[0008] Further, the docking recognition module triggers a magnetic field induction area at the bottom of the nursing device through the magnetic induction device, and judges docking success in cooperation with a reed tube signal, and the system controls a lock hook mechanism to lock the device.

[0009] Further, the posture adjustment module automatically sets target angles of the backrest and the leg support according to the type of the target nursing device, including a sitting posture, a supine position and a toilet posture, and can realize synchronous adjustment of the angles of the backrest and the leg support, supports arbitrary angle switching between the sitting posture and the supine position, and meets diversified needs of patient postures for different nursing tasks; the posture adjustment process is controlled by the system scheduling module, and the target angles are automatically set and adjustment commands are executed according to the type of the task.

[0010] Further, the flexible conveyor belt in the transfer execution module is arranged between the seat plate and the back plate of the wheelchair, and is started after the patient completes the docking with the nursing equipment. The conveyor belt is driven to run by the rollers, so that the patient is transferred in a lying state without lifting. When the patient's body triggers the end infrared sensor or the contact switch, the transfer execution module automatically stops running to prevent overpositioning or falling.

[0011] Further, the system scheduling module adopts a priority scheduling mechanism to realize task synchronization among the navigation control, attitude adjustment, and transfer execution modules through a message queue and a semaphore.

[0012] Further, the system further comprises a human-computer interaction module, which supports voice control, wireless remote control, and Hall rocker input. The voice module adopts a local offline recognition chip.

[0013] Further, the voice recognition adopts an LU-ASR01 module, supports recognizing multiple preset commands, and sends control instructions to the main control system through a serial port after recognition. The wireless remote control adopts an ASK mode signal, and the receiving module is connected through a GPIO interrupt mode. The Hall rocker input is converted into a motion speed instruction through periodic sampling of a voltage signal by an ADC, and is used for differential control in a manual mode.

[0014] A control method of a nursing wheelchair with autonomous docking function, based on the control system of the nursing wheelchair with autonomous docking function described above, comprises the following steps: Step one, the control mode recognition module judges the current task state and switches to a driving mode or an attitude transformation mode. In the driving mode, radar navigation or infrared tracking navigation is selected according to the navigation demand, including: in the global navigation stage, environment mapping and positioning are performed based on the laser radar and the inertial measurement unit, and an A* path planning algorithm is used to generate a global path to control the wheelchair to move to the target nursing equipment area; in the local precise docking stage, when the wheelchair enters the preset docking area, the tracking navigation mode is switched to, the ground guide line is recognized by the infrared tracking sensor array, and the path following is performed until the end point by combining the fuzzy PID algorithm. Step two, the docking recognition module detects the alignment state of the wheelchair and the target nursing equipment: after the local precise docking is completed, whether the wheelchair is accurately aligned is judged by the magnetic induction and the reed switch triggering device, and the structure state information of the target nursing equipment is received in real time to verify whether the preset docking safety condition is met. Step three, the attitude adjustment module adjusts the attitude of the wheelchair to adapt to the target equipment: after confirming the alignment and the safety state, the angle of the wheelchair backrest and the leg support is adjusted by the linkage control of the push rod motor according to the current nursing task type, so that it matches the platform geometric structure of the target nursing equipment. Step four, the transfer execution module realizes patient sliding transfer: after the posture adjustment is completed, the flexible conveying device is started, and the patient is smoothly slid to the target nursing platform through the roller motor driving the conveying belt; Step five, the system scheduling module coordinates the task execution of each module.

[0015] Further, in the docking process, the structure state of the target nursing equipment is checked in real time, including height, angle and brake state, and docking is only performed when the state meets the preset safety condition.

[0016] The present application has the following beneficial effects due to the adoption of the above technical solutions: The multifunctional nursing wheelchair control system provided by the present application can realize autonomous navigation, accurate docking and barrier-free transfer of various nursing platforms such as nursing beds, bathing cabins and toilet devices, significantly reducing manual intervention, reducing the labor intensity of nursing personnel, and improving the nursing efficiency and use comfort of long-term bedridden patients.

[0017] The system integrates laser radar navigation, infrared tracking navigation, posture linkage adjustment and roller conveying transfer and other core control modules, and can cope with path guidance and platform docking tasks in complex nursing environments, and has good environmental adaptability and positioning accuracy.

[0018] The control system supports multi-mode human-computer interaction and autonomous task scheduling, and combines an embedded real-time operating system to build a software and hardware closed-loop control architecture, improve the system response speed and stability, and has good expansibility and application promotion value.

[0019] The flexible conveying structure avoids the lifting action in traditional mechanical transfer, reduces the risk of patient falling, injury and other risks, improves the safety and comfort of the transfer process, and helps to improve the participation and independence of patients in the nursing process such as rehabilitation, toilet and bathing.

[0020] In summary, the present application has significant technical advantages in improving nursing efficiency, reducing labor costs, ensuring patient safety and improving user experience, and is suitable for various scenes such as nursing homes, rehabilitation centers and home care, and has broad industrialization and clinical promotion prospects. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is the overall structure schematic diagram of the multifunctional nursing wheelchair of the present application; Figure 2 is the layered architecture schematic diagram of the multifunctional nursing wheelchair control system of the present application; Figure 3 is the control flow chart of the multifunctional nursing wheelchair control system of the present application; Figure 4 is the function mode division diagram of the multifunctional nursing wheelchair of the present application; Figure 5 is a control circuit design schematic diagram of the stepping motor driving system of the application; Figure 6 is a serial communication data receiving flow chart of the application; Figure 7 is a manual control Hall rocker data acquisition and analysis flow chart of the application; Figure 8 is a fuzzy PID control strategy principle block diagram of the application; Figure 9 is an infrared tracking sensor array layout and tracking deviation judgment schematic diagram of the application; Figure 10 is an automatic docking process block diagram of the nursing equipment of the application; Figure 11 is a structure schematic diagram of the docking process of the multifunctional nursing wheelchair and the bathing cabin of the application. DETAILED DESCRIPTION

[0022] In order to make the technical means, creative features, purposes and effects of the application more clear, the following will combine the drawings and specific embodiments to explain the multifunctional nursing wheelchair autonomous docking and transfer control system and its control method in detail.

[0023] As shown in Figures 1 to 11 , the control system of the nursing wheelchair with autonomous docking function of the application comprises a control mode recognition module, a driving control module, a posture adjustment module, a docking recognition module, a transfer execution module and a system scheduling module. The control mode recognition module is used to recognize the current running task state of the wheelchair and switch the corresponding control process. The control mode comprises a driving mode and a posture transformation mode. The driving mode is further divided into a manual driving sub-mode and an automatic driving sub-mode. The user can switch the control mode through voice input, wireless remote control or Hall effect rocker. In the manual driving sub-mode, the wearer can use the rocker or remote control to control the driving direction and speed of the wheelchair in real time. The system realizes forward movement, backward movement and turning through differential drive. The manual driving control module determines the motion direction and speed of the wheelchair by collecting the dual-axis analog voltage signal of the Hall effect rocker. The front and rear axes control forward and backward movement, and the left and right axes control left and right turning. The analog signal is converted to digital signal and then acts on the dual-wheel differential motor drive system to realize stable motion control of the wheelchair in flat or indoor environment. In the automatic driving sub-mode, the system selects one of radar navigation and tracking navigation according to the navigation recognition result to realize path guidance. The radar navigation is based on the host computer path planning system, which realizes indoor environment mapping, positioning and path generation by fusing laser radar and IMU; The tracking navigation is based on the infrared tracking sensor array installed at the bottom of the wheelchair, which identifies the ground guide line deviation information, adjusts the driving wheel speed difference combined with the fuzzy PID control strategy, and realizes path tracking; After the navigation is completed, the system automatically switches to the posture transformation mode, adjusts the angle of the backrest and the leg support through the electric push rod to adapt to the geometric structure of the target nursing equipment, and prepares for patient transfer; The control system is developed based on an embedded real-time operating system platform, has multi-task concurrent scheduling capability, uses semaphore and message queue for task synchronization and switching, and realizes closed-loop control of path guidance, docking detection, posture adjustment and transfer process.

[0024] The docking identification module is used to judge whether the wheelchair and the target nursing equipment (such as a nursing bed, a bathing cabin, and a toilet device) are accurately aligned, the module includes a magnetic induction device, an infrared sensor array, a reed tube triggering device, and a contact switch structure; During the wheelchair retreat process, the tracking plate triggers the magnetic field induction area at the bottom of the nursing equipment, judges the docking success, and the system controls the hook mechanism to lock the equipment to ensure the structural stability and positioning accuracy during the transfer process.

[0025] The reed tube is arranged in the docking area of the target nursing platform to detect the magnetic field triggering event to judge the alignment state of the wheelchair; After the system receives the valid signal, it controls the docking claw mechanism to extend and complete mechanical cooperation with the wheelchair bottom locking device to form a stable docking relationship; After the docking completion signal is triggered, the transfer control module starts the execution program.

[0026] The transfer execution module adopts a flexible conveying structure, which includes a roller motor, a synchronous driving device, and a flexible conveying belt. The conveying device is arranged between the seat plate and the back plate of the wheelchair, the flexible conveying belt is driven by double rollers in synchronization, and the patient is slid from the wheelchair to the docking nursing platform along the horizontal direction; The roller motor is driven by a DC speed reducer, and a limit sensor is arranged. After the patient is docked with the nursing equipment, the roller belt is driven to run, realizing the no-lifting type sliding transfer of the patient in the lying state; When the patient's body triggers the end infrared sensor or the contact switch, the roller motor automatically stops running to prevent overtravel or falling. The system supports reverse sliding and automatic disengagement of the equipment after the task is completed, completing the whole transfer process.

[0027] The posture adjustment module includes a linkage push rod motor and a limit switch device, which can realize synchronous adjustment of the angle of the backrest and the leg support, support arbitrary angle switching between sitting and supine positions, and meet the diversified needs of patient body position for different nursing tasks (such as bathing, toilet, transfer, etc.); The posture adjustment process is controlled by the system scheduling module, which automatically sets the target angle and executes the adjustment command according to the task type.

[0028] The linkage push rod motor is controlled and driven by the PWM signal from the main control system to realize continuous angle adjustment of the backboard from 90° vertical to 0° horizontal, and the leg support is synchronously adjusted to form a complete supine or sitting posture. The limit switch is arranged at both ends of the push rod stroke to feed back the angle state signal in real time, so as to avoid posture over-adjustment or driving error. The posture adjustment is completed in the preset angle configuration before docking, and supports adaptive position fine adjustment in the toilet and bathing scenes.

[0029] The system scheduling module runs on an embedded real-time operating system platform, supports multi-thread task concurrent execution, and uses a priority scheduling mechanism to complete task switching and coordination among modules such as navigation control, posture adjustment, transfer execution and human-computer interaction. The inter-task communication is realized through message queues and semaphores to ensure the state synchronization and closed-loop control among modules.

[0030] The system supports three human-computer interaction modes of voice control, wireless remote control and Hall rocker. The voice module uses a local offline recognition chip to realize command analysis such as "forward", "dock", "toilet mode" and trigger the corresponding control process, which is suitable for users with limited hand function or cognitive impairment. The wireless remote control module supports one-key navigation and docking triggering to improve the operation convenience and accuracy. The Hall rocker supports continuous variable speed direction control to meet the high-precision manual driving demand.

[0031] When the wheelchair completes the navigation task and enters the preset docking area, the system automatically switches to the posture transformation mode, which adjusts the angle of the wheelchair backrest and leg support through linkage control of the push rod motor, adapts to the geometric structure of different docking platforms and prepares for transfer operation; The system scheduling module runs on an embedded real-time operating system platform, adopts a priority-based task scheduling strategy and signal synchronization mechanism to realize multi-module concurrent control. The scheduling module is responsible for the cooperative scheduling of wheelchair navigation, docking recognition, posture adjustment, transfer control and human-computer interaction tasks, and collects state feedback information in each task execution node for closed-loop control correction and task switching judgment to ensure stable, efficient and controllable nursing action process.

[0032] The above control process completes task coordination through an embedded real-time operating system scheduling platform, and each sub-module completes control mode switching and state synchronization through semaphores and message queues.

[0033] As Figure 1As shown, the overall structure of the multifunctional nursing wheelchair system of the application is composed of a wheelchair body, a motion driving assembly, a posture adjusting mechanism, a flexible transfer mechanism, a human-computer interaction module, and a control system. The wheelchair platform adopts a differential driving layout and has the capabilities of forward movement, backward movement, and in-place turning. The posture adjusting mechanism is composed of an electric push rod system linked by a back plate and a leg plate and can complete the switching of sitting, lying, and defecation postures. An openable seat cushion mechanism is arranged in the middle of the seat plate for defecation assistance. The system realizes multi-module cooperation through an integrated embedded control module, supports one-key switching to a specified nursing mode, and completes docking, transfer, and nursing operations.

[0034] As shown in Figure 2 , the navigation and docking control process first selects a nursing task by the user through remote control or voice instruction, and the system judges the target and starts the navigation program. In the initial stage, the wheelchair completes large-scale path planning and obstacle avoidance movement through the laser radar navigation function, switches to the infrared tracking mode when approaching the target, and accurately drives along the black line to the docking endpoint through the TCRT5000 sensor array at the bottom. When the tracking sensor recognizes all hits, the system triggers the stop command and judges the position ready, and then controls the wheelchair to enter the posture adjustment and docking hook locking stage, completes docking, and prepares for the transfer task.

[0035] As shown in Figure 3 , the posture adjusting control process is driven by the system control STM32 microcontroller outputting PWM signals to drive the push rod motor, and the motor forward and reverse switching is realized through the relay to realize the functions of lifting the back and bending the leg. A proximity sensor is arranged at the end of the push rod for limit protection. When the motor acts to the limit point, a stop signal is triggered to avoid overshoot damage. The push rod action sequence follows the requirements of the nursing mode. When switching to the defecation mode, the system first flattens the back, then opens the seat cushion, and finally retracts the tracking plate to leave space for the docking channel.

[0036] As shown in Figure 4 , the flexible transfer control process is started by the system after judging that the user has completed docking and the posture is correct, driving the flexible conveyor belt to act by the built-in roller motor, and sliding the user from the wheelchair to the target nursing platform. The motor is controlled by the relay in forward and reverse directions, and the position control is realized by software timing when the motor is running. When the contact switch on the target device side is triggered by the user's body, the system immediately closes the conveyor device, confirms that the transfer action is completed, and enters the next nursing process.

[0037] As shown in Figure 5As shown, the human-computer interaction module supports multi-modal control methods, including voice recognition, wireless remote control and Hall rocker input. The voice recognition uses the LU-ASR01 module, supports recognizing multiple preset commands, and sends control instructions to the main control system through the serial port after recognition; the wireless remote control uses ASK mode signals, and the receiving module is connected through the GPIO interrupt mode; the Hall rocker input is converted into a motion speed command through periodic sampling of the voltage signal by the ADC, which is used for differential control in manual mode. Each module thread runs in the RT-Thread operating system and is scheduled according to priority.

[0038] As shown in Figure 6 , the system implements a multi-thread scheduling mechanism based on the RT-Thread real-time operating system, and each control thread runs independently. The main control thread is responsible for mode management and state coordination, and the information interaction thread is responsible for serial port, voice and remote control command collection. The push rod control, motion control and transfer control are independent execution threads in the system and do not interfere with each other. Synchronization and mutual exclusion between modules are achieved through semaphore and event flag, ensuring the timeliness and responsiveness of task scheduling.

[0039] As shown in Figure 7 , the controller architecture adopts a three-layer structure of decision planning layer + system control layer + execution driving layer. The decision planning layer is deployed on the Jetson Nano industrial computer, which is used to run path planning, navigation obstacle avoidance and high-level logic; the system control layer takes the STM32F767 single-chip microcomputer as the core, collects sensor data and schedules motor drives; the execution layer includes push rod motors, roller motors and drive wheel stepper motors, which receive control instructions to complete specific actions. The three-layer architecture decouples to achieve high scalability and stability of the system.

[0040] As shown in Figure 8 , the flexible conveying device structure is composed of a pair of roller drive shafts, a surface flexible belt, a steering guide rail and a support frame. The transmission motor drives the conveyor belt to move linearly through the pulley, which can realize the horizontal sliding of the user's body. The device is arranged below the wheelchair seat plate and cooperates with the matching device in the nursing bed or bathing cabin to ensure the stability, low friction and safety of the body during the transition process. The contact switch signal is used to end the sliding.

[0041] As shown in Figure 9 , the voice recognition module communicates with the main control system through the serial port, and the system establishes an independent thread in RT-Thread for voice command recognition and response. The recognition chip locally processes the instructions and outputs the corresponding command number, which is parsed by the STM32 to trigger specific actions. The voice thread is a medium-priority task with high real-time performance. Typical control content includes "forward", "stop", "toilet mode", "bed docking" and other commands, which are suitable for users with severe disabilities.

[0042] As shown in Figure 10As shown, the docking detection structure is composed of wheelchair bottom magnet and nursing equipment bottom dry reed tube to trigger the response, which helps to determine the docking state. The dry reed tube guides the signal to indicate that the wheelchair has entered the designated area, and then the system controls the hook device of the nursing bed or the bathing cabin to extend and complete the mechanical locking. The two-way limit switch and control circuit ensure the accuracy and safety of the locking action, cooperate with the tracking navigation and end point judgment mechanism, and realize stable and reliable precise docking.

[0043] As shown, Figure 11 The conveyor wheelchair 1 is combined with the conveyor pad 2 for the patient's bathing. The motor control module controls the push rod motor, roller motor, etc. through the relay array in forward and reverse directions. The system listens to the control messages transmitted by the main control thread through the RT-Thread thread, outputs the GPIO level according to the target command, controls the direction of the relay attraction, and realizes actions such as lifting, pushing, and sliding. The limit switch or the set time is used to control the motor to stop, ensuring the accuracy and safety of the action. The control process adopts an event-driven mechanism to improve response efficiency.

Claims

1. A control system for a nursing wheelchair with autonomous docking function, characterized in that, include: The system includes a control mode recognition module, a driving control module, a posture adjustment module, a docking recognition module, a transfer execution module, and a system scheduling module. The control mode recognition module is used to identify the current operating status of the wheelchair and switch the control process and control mode. The control modes include driving mode and posture transformation mode. The driving control module is used to realize manual driving mode and automatic driving mode. The manual driving mode and automatic driving mode can be switched by inputting commands through the voice recognition module or wireless remote control. The automatic driving mode includes radar navigation and infrared tracking navigation. The posture adjustment module includes multiple linkage push rod structures and a limit detection device, used to adjust the backrest and leg rest angles of the wheelchair via electric push rods; It also supports adaptive position fine-tuning to fit the geometry of the target care device and prepare for patient transfer; The docking identification module includes a magnetic induction device, an infrared sensor array, a reed switch triggering device, and a contact switch, used to determine whether the wheelchair and the target nursing equipment are accurately aligned. The transfer execution module adopts a flexible conveying structure, including a roller motor, a synchronous drive device and a flexible conveyor belt, to realize the sliding transfer of the patient; The system scheduling module runs on an embedded real-time operating system and is used for multi-task concurrent scheduling and inter-module coordination.

2. The control system for the nursing wheelchair with autonomous docking function according to claim 1, characterized in that, In manual driving mode, the user can control the wheelchair's direction and speed in real time using a joystick or remote control, achieving forward, backward, and turning movements through differential drive. In automatic driving mode, the module selects either radar navigation or line-following navigation based on navigation recognition results for path guidance: radar navigation is based on a host computer path planning system, integrating lidar and IMU to achieve indoor environment mapping, positioning, and path generation; line-following navigation is based on an infrared line-following sensor array installed on the bottom of the wheelchair, identifying ground guide line offset information, and adjusting the speed difference of the drive wheels using a fuzzy PID control strategy to achieve path tracking.

3. The control system for the nursing wheelchair with autonomous docking function according to claim 1, characterized in that, The docking identification module triggers the magnetic field sensing area at the bottom of the nursing equipment through a magnetic induction device, and determines that the docking is successful in conjunction with the reed switch signal. The system then controls the locking hook mechanism to lock the equipment.

4. The control system for the nursing wheelchair with autonomous docking function according to claim 1, characterized in that, The posture adjustment module automatically sets the target angles of the backrest and leg rest according to the type of the target nursing equipment, including sitting, supine, and toileting positions. It can also achieve synchronous adjustment of the backrest and leg rest angles and support any angle switching between sitting and supine positions to meet the diverse needs of patients for different nursing tasks. The posture adjustment process is controlled by the system scheduling module, which automatically sets the target angle and executes the adjustment command according to the task type.

5. The control system for the nursing wheelchair with autonomous docking function according to claim 1, characterized in that, The flexible conveyor belt in the transfer execution module is located between the wheelchair seat and backrest. It is activated after the patient completes the docking with the nursing equipment. The conveyor belt is driven by rollers to achieve a non-lifting sliding transfer of the patient while lying down. When the patient's body triggers the endpoint infrared sensor or contact switch, the transfer execution module automatically stops to prevent over-distance or fall.

6. The control system for the nursing wheelchair with autonomous docking function according to claim 1, characterized in that, The system scheduling module adopts a priority scheduling mechanism and uses message queues and semaphores to achieve task synchronization between navigation control, attitude adjustment, and transfer execution modules.

7. The control system for the nursing wheelchair with autonomous docking function according to claim 1, characterized in that, It also includes a human-computer interaction module that supports voice control, wireless remote control and Hall effect joystick input. The voice module uses a local offline recognition chip.

8. The control system for the nursing wheelchair with autonomous docking function according to claim 7, characterized in that, The voice recognition uses the LU-ASR01 module, which supports the recognition of multiple preset commands. After recognition, the control command is sent to the main control system via serial port. The wireless remote control uses ASK signal, and the receiving module is connected via GPIO interrupt. The Hall joystick input is converted into a motion speed command by periodically sampling the voltage signal through ADC, which is used for differential control in manual mode.

9. A control method for a nursing wheelchair with autonomous docking function, based on the control system of the nursing wheelchair with autonomous docking function according to any one of claims 1-8, characterized in that, Includes the following steps: Step 1: The control mode recognition module determines the current task status and switches to driving mode or posture transformation mode. In driving mode, radar navigation or infrared tracking navigation is selected according to navigation needs, including: in the global navigation stage, environmental mapping and positioning are performed based on lidar and inertial measurement unit, and a global path is generated using A* path planning algorithm to control the wheelchair to move towards the target nursing equipment area; in the local precision docking stage, when the wheelchair enters the preset docking area, it switches to tracking navigation mode, identifies ground guide lines through infrared tracking sensor array, and follows the path until the destination using fuzzy PID algorithm; Step 2: The docking identification module detects the alignment status between the wheelchair and the target nursing equipment. After the local precise docking is completed, the magnetic induction and reed switch triggering device determine whether the wheelchair is in precise position, and receive the structural status information of the target nursing equipment in real time to verify whether the preset docking safety conditions are met. Step 3: The posture adjustment module adjusts the wheelchair posture to match the target equipment: After confirming that it is in place and safe, the push rod motor is linked to adjust the angle of the wheelchair backrest and leg rest according to the current nursing task type, so that it matches the platform geometry of the target nursing equipment. Step 4: The transfer execution module realizes the patient sliding transfer: After the posture adjustment is completed, the flexible conveyor is started, and the conveyor belt driven by the roller motor smoothly slides the patient to the target nursing platform; Step 5: The system scheduling module coordinates the execution of tasks from each module.

10. The control method for a nursing wheelchair with autonomous docking function according to claim 9, characterized in that, During the docking process, the structural status of the target nursing equipment is checked in real time, including its height, angle, and braking status. Docking is only performed when the status meets the preset safety conditions.

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