Lightweight load-assisting exoskeleton control method
By using an adaptive backplate, a rotating and opening thigh guard, and multi-signal judgment in a lightweight, weight-bearing walking mechanical exoskeleton, the problems of disconnect between the structure and control logic, insufficient accuracy of motion judgment, and inadequate safety protection in existing exoskeleton devices are solved, achieving efficient, safe, and convenient multi-scenario adaptation and improved user experience.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HUANGHE S & T COLLEGE
- Filing Date
- 2026-03-27
- Publication Date
- 2026-06-12
AI Technical Summary
Existing weight-bearing walking exoskeleton devices suffer from problems such as a disconnect between structure and control logic, insufficient accuracy in motion judgment, inadequate safety protection, unclear operation procedures, and weak adaptability, resulting in low assistance efficiency, high usage risk, cumbersome operation, and incompatibility with multiple scenarios.
It adopts a lightweight, weight-bearing walking mechanical exoskeleton device, including an adaptive back panel, a rotating and opening thigh guard, and a dual signal judgment and safety protection mechanism. Through self-testing, posture calibration, assistance level adjustment and safety protection steps, it achieves deep integration of structure and control logic, and is suitable for use in multiple scenarios.
It achieves precise, efficient, safe, reliable, and convenient operation, and is compatible with various scenarios such as walking on flat ground, bending over in place, and walking with loads. It improves the efficiency of assistance by 40%, reduces the failure rate by 60%, and enhances user experience and adaptability.
Smart Images
Figure CN122185127A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of mechanical exoskeleton assistive technology, and in particular relates to a control method for a lightweight, weight-bearing, walking-assistive mechanical exoskeleton. Background Technology
[0002] Mechanical exoskeletons are wearable robotic devices that enhance human mobility through a mechanical frame. Weight-bearing walking exoskeletons primarily improve walking endurance by assisting the hip joint and are widely used in outdoor weight-bearing, rehabilitation walking assistance, and industrial handling. Currently, existing weight-bearing walking exoskeletons and their corresponding control methods suffer from the following core shortcomings: (1) The device structure and control logic are disconnected: the back plate of the existing device has poor fit and will separate from the back of the human body when bending over, resulting in the distortion of the posture data collected by the gyroscope and the control method is prone to misjudgment of the action; the thigh guard plate adopts a single-sided arc plate, and the strap fixation is easy to loosen, resulting in loss of the assist torque transmission and a significant reduction in the assist efficiency of the control method; the motor and the support plate are rigidly connected, which cannot adapt to the natural left and right swing of the thigh, and is prone to motion interference, which limits the torque output range of the control method.
[0003] (2) Insufficient accuracy of motion judgment: Gait identification relies solely on a single sensor signal without combining the adaptability optimization of the device structure, which easily leads to assistance delay and false triggering. It is not compatible with multiple scenarios such as walking on flat ground, bending assistance, and walking with load, and requires manual mode switching, which is cumbersome.
[0004] (3) Inadequate safety protection mechanism: The device does not have redundant protection in combination with the mechanical structure, which can easily lead to problems such as sudden torque, excessive swing, and motor overheating, posing a risk to use. At the same time, the wearing experience is poor.
[0005] (4) Unclear operation process and weak adaptability: There is a lack of full-process operation guidance that matches the structure of the device. After users of different heights and body types adjust the device, the control logic cannot adapt to the user, making it difficult to get started. Summary of the Invention
[0006] To address the aforementioned deficiencies in existing technologies, this invention provides a control method for a lightweight, weight-bearing, assistive mechanical exoskeleton that is deeply integrated with a lightweight, weight-bearing, assistive mechanical exoskeleton device, offering precise and efficient assistance, safety and reliability, ease of operation, and compatibility with multiple scenarios.
[0007] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: A control method for a lightweight weight-bearing walking assistive mechanical exoskeleton is disclosed. The control method is based on a lightweight weight-bearing walking assistive mechanical exoskeleton device. The device includes a back support frame with a fixed shaft on its upper part along the left-right direction. A back plate that can adaptively conform to the human back is rotatably connected to the fixed shaft via a support. A battery pack is mounted on the back support frame, containing a rechargeable battery and a control board. A left hip assist frame and a right hip assist frame are connected to the lower left and right sides of the back support frame via left and right telescopic adjustment rods, respectively. The telescopic adjustment rods are locked to the back support frame via clamp assemblies. A left assist motor is located at the front end of the left hip assist frame. The main shaft of the left assist motor is connected to a left assist support plate via a left hinge. The left hinge includes a first hinge support, a second hinge support, and a hinge shaft. The center line of the hinge shaft intersects perpendicularly with the center line of the main shaft of the left assist motor, allowing the left assist support plate to swing slightly left and right around the hinge shaft. A rotating and opening left thigh guard assembly is located in the middle of the left assist support plate. The system includes a slotted seat containing meshing front and rear gears, which connect to the front and rear thigh guards respectively, enabling simultaneous opening and closing of both guards to wrap around the thighs. The lower end of the left assistive support plate is connected to a telescopically adjustable left lower limb support plate via a left joint bearing. The lower end of the left lower limb support plate is hinged to a left foot pedal via a foot hinge, and the left foot pedal contains a built-in left pressure sensor. The front end of the right hip assistive frame has a right assistive motor, which is connected to the right assistive support plate via a right hinge. The right assistive support plate has a rotating... The right thigh support assembly features a hinged design, with the lower end of the right assist plate connected to a retractable right lower limb support plate via a right joint bearing. The lower end of the right lower limb support plate is hinged to a right foot pedal with a built-in right pressure sensor. The left or right hip assist frame houses a gyroscope, and the outer protective shell contains a cooling fan. The top of the protective shell features a power button switch with a three-color LED indicator and a mode switch. The device also includes an audio output module. A foldable load-bearing plate is hinged to the lower part of the back support frame, and the load-bearing plate is supported by ropes. The control method includes the following steps: S1. Power-on self-test: Press and hold the power button for a preset time to power on the device. The control board will perform a full-process self-test, checking the connection and working status of the pressure sensor, gyroscope, left assist motor, right assist motor, cooling fan, power button, and mode switch. The fault type will be displayed by the LED indicator, and the fault will be announced via the audio output module. After the self-test is completed, the announcement will be made and the LED indicator will switch to power indication mode. S2. Attitude Calibration: After the self-test is completed, the device automatically enters the attitude calibration mode. The audio output module prompts the user to maintain the posture of standing with both feet on the ground and back against the back panel. Press the power button briefly to trigger the calibration. The control board calibrates the current attitude of the gyroscope to the 0° reference and calibrates the current spindle angles of the left and right auxiliary motors to the 0° reference. After the calibration is completed, prompts are output through LED indicator and audio module. S3, Assist Level Adjustment: After calibration, the device enters standby mode with an initial assist level of 0. Short press the mode switch button to cycle through the assist level. Each press increases the assist level by one, with a total of 5 adjustable assist levels. Each switch is announced through the audio output module. S4. Walking Assist Control: The device collects foot pressure signals in real time through pressure sensors on the left and right foot pedals, collects human posture angle signals in real time through a gyroscope, and collects main shaft angle signals in real time through the left and right assist motors. The control board judges human movement based on the three signals and outputs corresponding control commands to the left and right assist motors to achieve unified control of flat walking assistance, bending assistance, and weight-bearing walking assistance. S5. Safety Protection: During device operation, the control board monitors the swing angle of the main shaft of the left and right assist motors in real time. When the swing angle exceeds the preset ±60° limit range, the control motor torque is reduced to zero. When the assist direction or torque level is switched, the control board achieves a smooth torque transition through a preset torque gradient algorithm. At the same time, the motor temperature is monitored in real time. If the temperature exceeds the limit, the cooling fan is started, and the fan is turned off after cooling down. S6. Power off: Press and hold the power button for the preset time. The control board will control the torque of the booster motor to gradually decrease to zero. The power off prompt will be broadcast through the audio output module, the LED indicator will turn off, and the device will be powered off.
[0008] The flat-road walking assistance control in step S4 specifically includes: S4-1-1, Static Standing State Judgment: When the control board detects that the pressure values of both foot pressure sensors are higher than the preset threshold, the gyroscope angle is 0°, and the spindle angles of the left and right assist motors are 0°, it judges the state as static standing and controls the motors not to output assist torque. S4-1-2, Step Start Judgment: When the control board detects that the pressure on one foot is higher than the preset threshold (supporting foot), the pressure on the opposite foot is lower than the preset threshold (swinging foot), the gyroscope angle is positive (body leaning forward), and the main shaft angle of the swinging side motor is positive, it is judged as a step start; S4-1-3, Torque Output: The control board controls the support-side assist motor to output the corresponding level of assist torque, which is transmitted to the assist support plate through the hinge, and then transmitted to the support leg through the rotating and opening thigh guard assembly, driving the support leg to swing backward and propel the human body forward; at the same time, it controls the swing-side assist motor to output a low auxiliary torque, driving the swing-side assist support plate to swing forward and assist in lifting the leg; S4-1-4, Gait Switching: When the control board detects that the pressure on the original swing side foot rises to a preset threshold and the pressure on the original support side foot decreases, it determines that gait switching has occurred. It then controls the motors on both sides to stop the current torque output and switch to a new torque output logic for the support side and swing side, thus continuously assisting walking in a loop. S4-1-5, Stop walking judgment: When the control board detects that the pressure of both feet has returned to the stable threshold, the gyroscope angle is negative (body leaning back), and the main shaft angle of the motors on both sides returns to 0°, it judges that walking has stopped, controls the motor to stop outputting assist torque, and the device returns to standby state.
[0009] The in-situ bending assistance control in step S4 specifically includes: S4-2-1. When the control board detects that the pressure values of both foot pressure sensors are maintained at a stable threshold, the gyroscope angle is positive (body leaning forward), and the main shaft angles of both assist motors are positive, it determines that it is a bending-over motion in place. S4-2-2: The control board controls the left and right assist motors to output the corresponding level of assist torque synchronously, which is transmitted to the hip through the assist support plate and thigh guard plate assembly to provide the user with assistance in straightening the back; during this process, the back plate rotates around the fixed axis with the human body's bending movement, always in close contact with the human body's back, ensuring the accuracy of the gyroscope's attitude acquisition. S4-2-3. When the control board detects that the gyroscope angle has returned to 0° and the main shaft angle of the motors on both sides has returned to 0°, it determines that the upright state has been restored and controls the motor to stop outputting assist torque.
[0010] The weight-bearing walking assistance control in step S4 specifically includes: S4-3-1 The user unfolds the load-bearing support plate at the bottom of the backpack frame to a horizontal position, and places the heavy object on the load-bearing support plate with the support of the rope. The S4-3-2 control board detects increased plantar pressure through a foot pressure sensor and automatically matches the upper limit of the torque for the current assist level, thereby increasing the output torque threshold of the assist motor. S4-3-3 executes walking assistance control according to the control logic of walking assistance on flat roads. The load of heavy objects is transferred to the ground through the load-bearing support plate, back support, lower limb support plate, and foot pedal, reducing the pressure on the human body.
[0011] In step S1, the fault indication of the self-test process includes: when an abnormal connection of the pressure sensor or gyroscope is detected, the LED indicator displays a combination of red / green / yellow lights; when a motor fault is detected, the LED indicator displays a combination of red / blue lights, and a corresponding fault code is broadcast.
[0012] In step S2, after the attitude calibration is completed, the LED indicator flashes 3 times quickly, and the audio output module broadcasts a "calibration complete" message.
[0013] The torque gradient algorithm in step S5 uses a linear increment or S-curve transition method to achieve smooth torque switching, with a switching transition time of 100-300ms.
[0014] In steps S1 and S6, the preset duration for pressing and holding the power button is 3 seconds; when shutting down in step S6, the torque reduction time is 200-500ms to achieve a safe stop.
[0015] Using the above technical solution, the implementation of the control method of the present invention depends entirely on the structural features of the corresponding exoskeleton device. The functional correspondence between each component of the exoskeleton device and the control method is as follows: Back support frame: The load-bearing frame of the device provides the mounting base for components such as battery pack, hip assist frame, and load-bearing support plate, ensuring the installation stability of control-related components. It is the core of the connection between the device structure and control logic.
[0016] Fixed axis, support, and back plate: The back plate rotates freely around the fixed axis via the support, and can adaptively conform to the back as the human body bends or leans back, ensuring that the posture data collected by the gyroscope is completely synchronized with the actual posture of the human body, providing accurate reference data for the action judgment of the control method; the back plate is equipped with chest straps, abdominal straps, and shoulder straps to stably bind the device to the human body, prevent the device from shifting during the assistance process, and ensure effective torque transmission.
[0017] Battery pack: It has a built-in rechargeable battery and control board. The rechargeable battery powers all electrical components, and the control board is the core control unit of this method. It receives all sensor signals, executes control logic, and outputs motor control commands.
[0018] Left telescopic adjustment rod, right telescopic adjustment rod, and clamp assembly: used to adjust the spacing of the left and right hip assist frames to accommodate different users' hip widths, ensure that the main shaft of the assist motor is coaxial with the human hip joint, and make the torque output by the control method consistent with the direction of human hip joint movement to avoid torque deviation.
[0019] Left hip assist frame and right hip assist frame: symmetrically arranged on the left and right sides, providing mounting platforms for the left assist motor, right assist motor and gyroscope, while also having built-in cooling fans to support motor heat dissipation and ensure stable operation of the motor under all operating conditions of the control method.
[0020] Left and right assist motors: The power execution units of the device adopt the Yushu GO-M8010-6 torque motor. They receive instructions from the control board and output stress torque to drive the assist support plate to swing and achieve assistive walking. At the same time, they provide real-time feedback of the main shaft angle signal to the control board, providing core data for action judgment.
[0021] Left and right hinges: connecting the main shaft of the power assist motor and the power assist support plate, consisting of a first hinge support, a second hinge support, and a hinge shaft. The hinge shaft is perpendicular to the main shaft of the motor, allowing the power assist support plate to swing slightly left and right around the hinge shaft in addition to swinging back and forth, adapting to the natural left and right swinging motion of the human thigh, and avoiding motion interference when the control method outputs torque.
[0022] Rotating and opening left / right thigh guard assembly: includes a slotted seat, meshing front and rear gears, front / rear rotating plates, front / rear arc-shaped connecting plates, front thigh guard, and rear thigh guard. The meshing gears enable the simultaneous opening and closing of the two guards, wrapping and fixing the thighs, and transmitting 100% of the torque of the assistive support plate to the human body with no power loss, ensuring that the assistive effect of the control method is fully realized.
[0023] Anti-friction trouser rotating disc: Rotated inside the support plate, it converts the sliding friction between the trousers and the support plate into rolling friction, avoiding damage to the trousers caused by prolonged walking, improving wearing comfort, and ensuring that the device fits stably against the human body throughout the entire control process.
[0024] Left and right joint bearings: connect the support plate and the lower limb support plate, allowing the lower limb support plate to swing in multiple directions with small amplitudes, adapting to the natural movement of the human knee joint and avoiding restriction of knee joint movement when the control method is in operation.
[0025] Left lower limb support plate and right lower limb support plate: They are divided into retractable upper and lower sections, which are locked by connecting bolts. The length can be adjusted to suit the leg length of different users. At the same time, the weight of the device is transferred to the foot pedal, reducing the pressure on the human body and adapting to the control logic of weight-bearing walking.
[0026] Left foot pedal 35, right foot pedal: including vertical connecting plate, horizontal pedal, foot hinge, foot strap. The horizontal pedal has a built-in pressure sensor to collect the pressure signal of the sole of the foot in real time and transmit it to the control board to provide core support data for gait judgment. The foot hinge adapts to the swinging movement of the human foot when walking, ensuring that the pressure sensor fits tightly with the sole of the shoe and the data is collected accurately.
[0027] Gyroscope: Located inside the left or right hip support frame, it collects human posture angle signals in real time and transmits them to the control board, providing core posture data for motion judgment.
[0028] Power button switch: with three-color LED indicator, used for powering on, powering off, and attitude calibration confirmation of the device. At the same time, the LED indicator also provides visual prompts for faults, power level, and calibration status.
[0029] Mode switch button: Used to cycle through the assistance levels to adapt to the assistance needs and usage scenarios of different users.
[0030] Audio output module: used for fault reporting, operation prompts, and status announcements, improving ease of operation and reducing the learning curve for users.
[0031] Cooling fan: Located inside the protective shell of the hip assist frame, it receives instructions from the control board to blow air to cool the assist motor and ensure the stability of the motor during long-term operation.
[0032] Load-bearing support plate and rope: The load-bearing support plate is hinged to the lower part of the back support frame. It can be folded and stored. When unfolded, it is supported by ropes to carry heavy objects. The load of the heavy objects is transferred to the ground through the device, reducing the pressure on the human body and adapting to the control logic of carrying heavy objects.
[0033] In summary, the control method of the present invention includes six major steps: power-on self-test, posture calibration, assist level adjustment, walking assistance control, safety protection, and power-off. The specific overall technical effects of the technical solution are as follows: 1) Deep integration of device structure and control logic for precision and efficiency: The adaptive backplate ensures accurate posture data acquisition, the wrap-around rotating thigh guard ensures lossless torque transmission, and the hinges and joint bearings adapt to the natural movements of the human body to avoid interference. This allows the control logic of triple signal fusion to be fully implemented, with an action recognition accuracy of over 99%, no assist delay, no action misjudgment, and assist efficiency improved by more than 40% compared to existing solutions.
[0034] 2) High safety and reliability: The device features dual protection based on its structure. On the mechanical level, it has a ±60° motor swing angle limit. On the control level, it has a torque gradual change algorithm, motor overheat protection, and emergency stop response mechanism to prevent injury from abnormal wear and torque imbalance. The device's failure rate is reduced by 60%, and the safety of use is greatly improved.
[0035] 3) Easy to operate and highly adaptable: The device features a full-process operation guide that matches its structure, along with LED visual prompts and voice broadcasts, allowing users to quickly get started. The device's hip width and leg length are freely adjustable, and the control method can adapt to users of different heights and body types. It also features 5 adjustable levels of assistance to meet the needs of users with different physical strength and load conditions.
[0036] 4) Good scene compatibility: A unified control system is implemented for walking on flat ground, bending over in place, and walking with load through a set of control logic. There is no need to manually switch modes. It can be adapted to various scenarios such as outdoor load-bearing, rehabilitation walking assistance, and industrial handling, which greatly improves the practicality of the device.
[0037] 5) Excellent wearing comfort: The movable structure of the control logic adaptation device perfectly matches the natural limb movements of the human body, without movement interference or jamming. Combined with the anti-abrasion pants rotating disc, flexible straps and other structures, there is no discomfort even after wearing for a long time, greatly improving the user experience.
[0038] 6) Highly portable and easy to store: The shutdown process of the control method is compatible with the easy-to-disassemble and foldable structure of the device. After shutdown, the device can be folded and stored, occupying only 1 / 3 of the space when in use, which is convenient for transportation and storage. Attached Figure Description
[0039] Figure 1 This is a schematic diagram of the front three-dimensional structure of the lightweight load-bearing walking mechanical exoskeleton device on which the present invention is based; Figure 2 This is a front structural schematic diagram of the lightweight load-bearing walking mechanical exoskeleton device on which the present invention is based; Figure 3 This is a schematic diagram of the rear three-dimensional structure of the lightweight load-bearing walking mechanical exoskeleton device on which the present invention is based; Figure 4 This is a flowchart of the lightweight load-bearing walking mechanical exoskeleton control method of the present invention; Figure labels: 1-Back support frame; 2-Battery pack; 3-Left hip assist frame; 4-Right hip assist frame; 5-Left assist motor; 6-Left assist support plate; 7-Right assist motor; 8-Right assist support plate; 9-Left telescopic adjustment rod; 10-Right telescopic adjustment rod; 11-Holding assembly; 12-Fixed shaft; 13-Support; 14-Back panel; 15-Chest strap; 16-Abdominal strap; 17-Left shoulder strap; 18-Right shoulder strap; 19-First hinge support; 20-Second hinge support; 21-Hinge shaft; 22-Front gear; 23-Rear gear; 24-Front rotating plate; 25 26-Front arc-shaped connecting plate; 27-Front thigh guard; 28-Rear rotating plate; 29-Rear arc-shaped connecting plate; 30-Rear thigh guard; 31-Thigh strap; 32-Anti-abrasion pants rotating disc; 33-Slotted seat; 34-Left joint bearing; 35-Left lower limb support plate; 36-Left foot pedal; 37-Right joint bearing; 38-Right lower limb support plate; 39-Right foot pedal; 40-Rope; 41-Connecting bolt; 42-Vertical connecting plate; 43-Horizontal pedal; 44-Foot hinge; 45-Foot strap; 46-Mode switch button; 47-Power button switch. Detailed Implementation
[0040] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The described embodiments are only used to explain the present invention and are not intended to limit the scope of protection of the present invention.
[0041] The lightweight load-bearing assistive mechanical exoskeleton control method of this embodiment is based on a lightweight load-bearing assistive mechanical exoskeleton device. The specific working process is as follows, with all components participating in the corresponding process: I. Wearing and Fitting Preparation Before implementing the control method, the device and the user must be properly adapted and adjusted: Hip width adjustment: Loosen the clamp assembly 11, and according to the user's hip width, pull out the left telescopic adjustment rod 9 and the right telescopic adjustment rod 10 to insert into the back support 1. Adjust the distance between the left hip assist frame 3 and the right hip assist frame 4 to fit the human hip. Then tighten the clamp assembly 11 to ensure that the assist motor spindle is coaxial with the human hip joint. Leg length adjustment: Loosen the connecting bolts 41 of the left lower limb support plate 34 and the right lower limb support plate 37, pull out the upper and lower sections to adjust the overlap length to fit the user's leg length, and tighten the connecting bolts 41 after adjustment. Back support fixation: Untie the chest strap 15, abdomen strap 16, left shoulder strap 17, and right shoulder strap 18. The user's back should fit against the back panel 14. Wrap the shoulder straps around the shoulders and then tighten the chest strap 15 and abdomen strap 16 in sequence. At this time, the back panel 14 can rotate freely around the fixed axis 12 via the support 13, and adapt to the posture of the human back. Thigh fixation: Untie the thigh straps 30, rotate the front thigh guard plate 26 forward to drive the front gear 22 to rotate, and the meshing rear gear 23 to rotate in the opposite direction, driving the rear thigh guard plate 29 to rotate backward synchronously, opening the guard plate; place the human thigh between the front and rear guard plates, rotate the front thigh guard plate 26 in the opposite direction, the two guard plates rotate towards each other to wrap around the front and back sides of the thigh, tighten the thigh straps 30 to make the guard plate fit tightly against the thigh; Foot fixation: The user places both feet on the horizontal pedals 43 of the left foot pedal 35 and the right foot pedal 38 respectively, and wraps the foot straps 45 around the shoes and locks them in place, ensuring that the pressure sensors inside the horizontal pedals 43 fit tightly against the sole of the shoe without obstruction.
[0042] II. Power-on self-test steps S1 Press and hold the power button switch with the three-color LED indicator for 473 seconds. The rechargeable battery in battery pack 2 will power the control board, gyroscope, left assist motor 5, right assist motor 7, pressure sensor, audio output module, cooling fan, and button module, and the device will start up. The control board performs a full-process self-test, sequentially checking: the connection and signal transmission status of the pressure sensors built into the left foot pedal 35 and right foot pedal 38; the working status of the gyroscope in the hip assist frame; the drive, angle feedback, and temperature detection status of the left assist motor 5 and right assist motor 7; the start / stop status of the cooling fan; the on / off status of the power button switch 47 and mode switch button 46; and the smoothness of rotation of the back plate 14 and the locking status of the telescopic adjustment rod. If a sensor malfunction is detected, the LED indicator will display a combination of red / green / yellow lights, and the audio output module will broadcast the corresponding fault code. If a motor malfunction is detected, the LED indicator will display a combination of red / blue lights, and the corresponding fault code will be broadcast. After all components have completed their self-tests, the audio output module announces "Self-test complete," and the LED indicator switches to power indicator mode, displaying the corresponding color based on the remaining battery power.
[0043] III. Attitude Calibration Step S2 After the self-test is completed, the device automatically enters the attitude calibration mode, and the audio output module announces "Please keep your feet upright, back against the back panel, and press the power button briefly to complete the calibration". The user maintains a natural standing posture with both feet, an upright body, and the back against the back plate 14. The back plate 14 is fully attached to the back of the human body through the support 13 around the fixed axis 12, ensuring that the gyroscope is synchronized with the human body posture. A short press of the power button 47 triggers the calibration operation on the control board, calibrating the current upright posture of the gyroscope to the 0° reference, and calibrating the current spindle angles of the left boost motor 5 and the right boost motor 7 to the 0° reference. After calibration is complete, the LED indicator flashes three times quickly, the audio output module announces "calibration complete", and the device enters standby mode.
[0044] IV. Steps to Adjust Assist Level (S3) After calibration, the device's initial assist level is 0, with no assist output; The user can press the mode switch button 46 briefly. Each short press increases the assist level by one level. There are 1 to 5 adjustable assist levels. The higher the level, the greater the maximum torque output by the assist motor. Each time the assist level is switched, the audio output module will announce "Current assist level X". After cycling through to level 5, pressing again will return to level 0.
[0045] V. Assistive Walking Control Steps S4 During device operation, the control board receives in real time the plantar pressure signals collected by the pressure sensors of the left foot pedal 35 and the right foot pedal 38, the human posture angle signals collected by the gyroscope, and the spindle angle signals collected by the left assist motor 5 and the right assist motor 7. Based on these three signals, the control board executes the following control logic: (1) Level Road Walking Assist Control S4-1-1 Static Standing State Judgment: When the pressure values of the left and right pressure sensors of both feet are higher than the preset standing pressure threshold (fluctuation ≤5%), the gyroscope angle is 0°, and the left and right motor spindle angles are 0°, the control board judges it as a static standing state, controls the left and right assist motors not to output assist torque, the device remains in standby mode, the cooling fan is in standby mode, and the anti-abrasion pants rotating disk 31 is in contact with the inside of the pants without rotation.
[0046] S4-1-2 Step-start Judgment: Taking the left foot on the ground and the right foot raised to take a step as an example, the pressure sensor of the left foot pedal 35 detects a pressure value ≥90% of the standing pressure threshold, and the pressure sensor of the right foot pedal 38 detects a pressure value ≤10% of the standing pressure threshold; the gyroscope detects that the body is leaning forward and the angle is positive; the main shaft of the right assist motor 7 swings forward with the right leg and the angle is positive; the control board combines the three signals to determine that it is a "left foot support, right foot step" starting action.
[0047] S4-1-3 Torque Output: Based on the currently set assist level, the control board outputs a counter-torque command to the left assist motor 5. The left assist motor 5 drives the left assist support plate 6 to swing backward (negative angle) through the left hinge. The rotating and opening left thigh guard assembly on the left assist support plate 6 transmits the torque to the left leg without loss, pushing the left leg to swing backward and providing the main force for the body to move forward. At the same time, the right assist motor 7 outputs a low auxiliary torque command, driving the right assist support plate 8 to swing forward (positive angle) to assist the right leg in lifting and taking a step. During this process, the cooling fan works synchronously with the motor to blow air and dissipate heat for the motor; the left and right assistive support plates swing slightly left and right around the hinge axis 21 via the hinge joint to adapt to the natural movement of the thigh; the anti-friction trouser rotating disc 31 on the inner side of the left assistive support plate 6 and the right assistive support plate 8 rotates with the thigh swing and rubs against the trousers to prevent the trousers from tearing; the left lower limb support plate 34 and the right lower limb support plate 37 swing slightly via the joint bearing to adapt to the movement of the knee joint without movement interference.
[0048] S4-1-4 Gait Switching: When the right foot steps forward and lands, the pressure sensor of the right foot pedal 38 detects that the pressure value rises to ≥90% of the standing threshold. The pressure of the left foot has not yet decreased, and the control board controls the left and right motors to stop the current torque output. The user shifts their body weight forward, switching to a right-foot-on-the-ground and left-foot-off-the-ground configuration. The pressure on the right foot remains high, while the pressure on the left foot drops to ≤30% of the standing threshold. The main shaft of the right assist motor 7 swings to the correct angle. The control panel determines that the user is "supporting with the right foot and stepping with the left foot," and controls the right assist motor 7 to output the corresponding level of assist torque, causing the right assist support plate 8 to swing backward to provide the main force for forward movement. The left assist motor 5 outputs a low assist torque, causing the left assist support plate 6 to swing forward to assist the left leg in lifting and stepping. This logic loop provides continuous walking assistance. The control board also adjusts the torque output speed in real time based on the pressure change rate of the pressure sensor to adapt to different walking speeds.
[0049] S4-1-5 Stop Walking Judgment: The user slows down, leans back naturally, the gyroscope detects a negative angle, the left and right motor spindles gradually return to 0°, and both foot pressure sensors recover to a stable standing pressure threshold (fluctuation ≤5%); the control board judges that walking has stopped, controls the motor to stop outputting torque, the cooling fan shuts down after a 30-second delay, and the device returns to standby mode.
[0050] (2) Bending over in place to assist control S4-2-1 Action Judgment: When the user's feet are parallel to the ground, the foot pressure sensors detect a stable standing threshold (fluctuation ≤8%), the body leans forward and bends over, the gyroscope detects a positive angle, and the left and right assist motor spindles swing to the positive angle with the hips; the control panel judges this as a bending over motion in place.
[0051] S4-2-2 Torque Output: The control board controls the left and right assist motors to synchronously output the assist torque of the current level, which is transmitted to the hip through the left and right assist support plates and thigh guard plate assembly, providing the user with an assist torque to straighten their back and reduce the burden on the waist; during this process, the back plate 14 rotates around the fixed axis 12 with the human body's bending motion, always fitting the human back, ensuring the accuracy of the gyroscope's posture acquisition; the hinge and joint bearing adapt to the limb movements when bending over, and the anti-abrasion pants rotating disc 31 rotates with the slight swing of the thigh.
[0052] S4-2-3 Stop Assist: The user straightens their back and returns to an upright position, the gyroscope angle returns to 0°, the left and right motor spindles reset to 0°, and the pressure on both feet returns to the initial standing threshold; the control board judges that the user is in an upright position, controls the motor to stop outputting assist torque, and the device returns to standby mode.
[0053] (3) Weight-bearing walking assistance control After the user has put on the device, rotate the load-bearing support plate 39 at the bottom of the back support 1 downwards around the hinge point to a horizontal state, pass the middle section of the rope 40 through the left rope hole and the right rope hole of the load-bearing support plate 39 in sequence, so that the rope 40 is supported at the bottom of the load-bearing support plate 39, and place the weight on the load-bearing support plate 39. The S4-3-2 control board detects increased foot pressure through a foot pressure sensor, automatically matches the torque limit of the current assist level, and increases the output torque threshold of the assist motor to adapt to heavy-load scenarios. S4-3-3 executes walking assistance control according to the control logic of walking assistance on flat roads. The load of the heavy object is transferred to the ground through the load-bearing support plate 39, rope 40, back support 1, lower limb support plate, vertical connecting plate 42, and foot pedal, rather than acting directly on the human body, effectively reducing the load pressure on the back and waist of the human body.
[0054] VI. Safety Protection Steps S5 During device operation, the control board monitors the swing angle of the main shaft of the left and right assist motors in real time. The preset maximum swing angle is ±60°. When the motor swing angle exceeds this range, the control board immediately controls the motor torque to drop to zero to prevent injury caused by abnormal wear. When the power assist direction is switched or the power assist level is adjusted, the control board uses a linear incremental or S-curve torque gradient algorithm to complete the smooth transition of torque within 100-300ms, avoiding discomfort and imbalance caused by sudden torque changes. Meanwhile, the control board monitors the motor temperature in real time. When the temperature exceeds the preset threshold of 55℃, the cooling fan is activated. When the temperature drops below 45℃, the fan is turned off to ensure stable motor operation.
[0055] VII. Power off procedure S6 Press and hold the power button for 473 seconds. The control board will trigger the shutdown process. First, the torque of the power assist motor will be gradually reduced to zero within 200-500ms to avoid imbalance caused by sudden stop. Then, the audio output module will announce "Device shutdown", the LED indicator will turn off, the power supply of battery pack 2 will be cut off, and the device will be shut down. After powering off, the user unfastens all straps and releases the device, folds the load-bearing support plate 39 to fit the back support 1, and retracts the telescopic adjustment rod and lower limb support plate to their shortest length to complete storage.
[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.
Claims
1. A lightweight load-bearing assistive mechanical exoskeleton control method, characterized in that: The control method described is based on a lightweight weight-bearing walking mechanical exoskeleton device. This device includes a back support frame with a fixed shaft on its upper part along the left-right direction. A back plate that can adaptively conform to the human back is rotatably connected to the fixed shaft via a support. A battery pack is mounted on the back support frame, containing a rechargeable battery and a control board. A left hip assist frame and a right hip assist frame are connected to the lower left and right sides of the back support frame via left and right telescopic adjustment rods, respectively. The telescopic adjustment rods are locked to the back support frame via a clamp assembly. A left assist motor is located at the front end of the left hip assist frame. The main shaft of the left assist motor is connected to a left assist support plate via a left hinge. The left hinge includes a first hinge support, a second hinge support, and a hinge shaft. The center line of the hinge shaft intersects perpendicularly with the center line of the main shaft of the left assist motor, allowing the left assist support plate to swing slightly left and right around the hinge shaft. A rotating and opening left thigh guard assembly is located in the middle of the left assist support plate. The left thigh guard assembly includes a groove-shaped seat. The seat contains meshing front and rear gears, which connect to the front and rear thigh guards respectively, enabling the dual guards to open and close synchronously to wrap around the thighs. The lower end of the left assistive support plate is connected to a retractable and adjustable left lower limb support plate via a left joint bearing. The lower end of the left lower limb support plate is hinged to a left foot pedal via a foot hinge, and the left foot pedal has a built-in left pressure sensor. The front end of the right hip assistive frame has a right assistive motor, which is connected to the right assistive support plate via a right hinge. The right assistive support plate has a rotating and opening right thigh guard assembly. The lower end of the right assistive support plate is connected to a retractable right lower limb support plate via a right joint bearing, and the lower end of the right lower limb support plate is hinged to a right foot pedal with a built-in right pressure sensor. A gyroscope is installed inside either the left or right hip assistive frame, and a cooling fan is installed inside the outer protective shell. The top of the protective shell has a power button switch with a three-color LED indicator, a mode switch button, and an audio output module. A foldable load-bearing support plate is hinged to the lower part of the back support, and the load-bearing support plate is supported by ropes. The control method includes the following steps: S1. Power-on self-test: Press and hold the power button for a preset time to power on the device. The control board will perform a full-process self-test, checking the connection and working status of the pressure sensor, gyroscope, left assist motor, right assist motor, cooling fan, power button, and mode switch. The fault type will be displayed by the LED indicator, and the fault will be announced via the audio output module. After the self-test is completed, the announcement will be made and the LED indicator will switch to power indication mode. S2. Attitude Calibration: After the self-test is completed, the device automatically enters the attitude calibration mode. The audio output module prompts the user to maintain the posture of standing with both feet on the ground and back against the back panel. Press the power button briefly to trigger the calibration. The control board calibrates the current attitude of the gyroscope to the 0° reference and calibrates the current spindle angles of the left and right auxiliary motors to the 0° reference. After the calibration is completed, prompts are output through LED indicator and audio module. S3, Assist Level Adjustment: After calibration, the device enters standby mode with an initial assist level of 0. Short press the mode switch button to cycle through the assist level. Each press increases the assist level by one, with a total of 5 adjustable assist levels. Each switch is announced through the audio output module. S4. Walking Assist Control: The device collects foot pressure signals in real time through pressure sensors on the left and right foot pedals, collects human posture angle signals in real time through a gyroscope, and collects main shaft angle signals in real time through the left and right assist motors. The control board judges human movement based on the three signals and outputs corresponding control commands to the left and right assist motors to achieve unified control of flat walking assistance, bending assistance, and weight-bearing walking assistance. S5. Safety Protection: During device operation, the control board monitors the swing angle of the main shaft of the left and right assist motors in real time. When the swing angle exceeds the preset ±60° limit range, the control motor torque is reduced to zero. When the assist direction or torque level is switched, the control board achieves a smooth torque transition through a preset torque gradient algorithm. At the same time, the motor temperature is monitored in real time. If the temperature exceeds the limit, the cooling fan is started, and the fan is turned off after cooling down. S6. Power off: Press and hold the power button for the preset time. The control board will control the torque of the booster motor to gradually decrease to zero. The power off prompt will be broadcast through the audio output module, the LED indicator will turn off, and the device will be powered off.
2. The lightweight load-bearing assistive mechanical exoskeleton control method according to claim 1, characterized in that: The flat-road walking assistance control in step S4 specifically includes: S4-1-1, Static Standing State Judgment: When the control board detects that the pressure values of both foot pressure sensors are higher than the preset threshold, the gyroscope angle is 0°, and the spindle angles of the left and right assist motors are 0°, it judges the state as static standing and controls the motors not to output assist torque. S4-1-2, Step Start Judgment: When the control board detects that the pressure on one foot is higher than the preset threshold (supporting foot), the pressure on the opposite foot is lower than the preset threshold (swinging foot), the gyroscope angle is positive (body leaning forward), and the main shaft angle of the swinging side motor is positive, it is judged as a step start; S4-1-3, Torque Output: The control board controls the support-side assist motor to output the corresponding level of assist torque, which is transmitted to the assist support plate through the hinge, and then transmitted to the support leg through the rotating and opening thigh guard assembly, driving the support leg to swing backward and propel the human body forward; at the same time, it controls the swing-side assist motor to output a low auxiliary torque, driving the swing-side assist support plate to swing forward and assist in lifting the leg; S4-1-4, Gait Switching: When the control board detects that the pressure on the original swing side foot rises to a preset threshold and the pressure on the original support side foot decreases, it determines that gait switching has occurred. It then controls the motors on both sides to stop the current torque output and switch to a new torque output logic for the support side and swing side, thus continuously assisting walking in a loop. S4-1-5, Stop walking judgment: When the control board detects that the pressure of both feet has returned to the stable threshold, the gyroscope angle is negative (body leaning back), and the main shaft angle of the motors on both sides returns to 0°, it judges that walking has stopped, controls the motor to stop outputting assist torque, and the device returns to standby state.
3. The lightweight load-bearing assistive mechanical exoskeleton control method according to claim 1, characterized in that: The in-situ bending assistance control in step S4 specifically includes: S4-2-1. When the control board detects that the pressure values of both foot pressure sensors are maintained at a stable threshold, the gyroscope angle is positive (body leaning forward), and the main shaft angles of both assist motors are positive, it determines that it is a bending-over motion in place. S4-2-2: The control board controls the left and right assist motors to output the corresponding level of assist torque synchronously, which is transmitted to the hip through the assist support plate and thigh guard plate assembly to provide the user with assistance in straightening the back; during this process, the back plate rotates around the fixed axis with the human body's bending movement, always in close contact with the human body's back, ensuring the accuracy of the gyroscope's attitude acquisition. S4-2-3. When the control board detects that the gyroscope angle has returned to 0° and the main shaft angle of the motors on both sides has returned to 0°, it determines that the upright state has been restored and controls the motor to stop outputting assist torque.
4. The lightweight load-bearing walking mechanical exoskeleton control method according to claim 1, characterized in that: The weight-bearing walking assistance control in step S4 specifically includes: S4-3-1 The user unfolds the load-bearing support plate at the bottom of the backpack frame to a horizontal position, and places the heavy object on the load-bearing support plate with the support of the rope. The S4-3-2 control board detects increased plantar pressure through a foot pressure sensor and automatically matches the upper limit of the torque for the current assist level, thereby increasing the output torque threshold of the assist motor. S4-3-3 executes walking assistance control according to the control logic of walking assistance on flat roads. The load of heavy objects is transferred to the ground through the load-bearing support plate, back support, lower limb support plate, and foot pedal, reducing the pressure on the human body.
5. The lightweight load-bearing assistive mechanical exoskeleton control method according to claim 1, characterized in that: In step S1, the fault indication of the self-test process includes: when an abnormal connection of the pressure sensor or gyroscope is detected, the LED indicator displays a combination of red / green / yellow lights; when a motor fault is detected, the LED indicator displays a combination of red / blue lights, and a corresponding fault code is broadcast.
6. The lightweight load-bearing assistive mechanical exoskeleton control method according to claim 1, characterized in that: In step S2, after the attitude calibration is completed, the LED indicator flashes 3 times quickly, and the audio output module broadcasts a "calibration complete" message.
7. The lightweight load-bearing assistive mechanical exoskeleton control method according to claim 1, characterized in that: The torque gradient algorithm in step S5 uses a linear increment or S-curve transition method to achieve smooth torque switching, with a switching transition time of 100-300ms.
8. The lightweight load-bearing assistive mechanical exoskeleton control method according to claim 1, characterized in that: In steps S1 and S6, the preset duration for pressing and holding the power button is 3 seconds; when shutting down in step S6, the torque reduction time is 200-500ms to achieve a safe stop.