Active robotic knee brace system and method for assisting mobility in paraplegic individuals

Abstract

The invention pertains to an active robotic knee brace system designed to assist mobility in paraplegic individuals. It comprises a plurality of inertial measurement units (IMUs), including a first IMU sensor module (2) and a second IMU sensor module (7), and electromyography (EMG) sensors, including a first EMG signal module (1) and a second EMG signal module (8), to capture real-time motion data and detect muscular activity. A rotary type absolute encoder (5) provides angular position feedback, while a control unit and power source compartment (3) processes data to generate torque commands. An electric actuator (6) applies force to assist knee joint motion, with an upper part (4) and lower part (9) connected by adjustable attachment mechanisms (10, 11) for secure fitting. The system utilizes sensor fusion to dynamically adapt to the user's gait cycle, offering real-time responsive support.

Description

[0001] FIELD OF THE INVENTION

[0002] The present invention generally relates to the field of assistive devices for individuals with mobility impairments, and more particularly to an active robotic knee brace system and method designed to assist mobility in paraplegic individuals by providing enhanced support and adaptive movement capabilities.

[0003] BACKGROUND OF THE INVENTION

[0004] Paraplegia results in significant mobility impairment, affecting the quality of life for individuals who often sustain such injuries at a young age. The inability to walk or stand independently not only limits personal autonomy but also leads to secondary health issues, including muscle atrophy, decreased bone density, and cardiovascular problems. For those affected, regaining mobility is crucial to improving their overall well-being and independence.

[0005] Historically, passive orthotic devices such as long-leg braces and reciprocating gait orthoses (RGOs) have been employed to aid mobility. These devices provide structural support but require substantial upper body strength to operate, resulting in slow movement and high physical exertion. Additionally, passive orthoses lack the capability to adapt to dynamic movements or offer adequate assistance during complex tasks, limiting their effectiveness.

[0006] The introduction of powered orthoses has sought to overcome the limitations of passive devices by incorporating actuators and sensors to facilitate movement. These systems aim to reduce user effort and promote more natural gait patterns. Despite these advancements, current powered orthoses often suffer from issues such as excessive bulk, limited responsiveness, and inadequate torque, which hinder their practical application.

[0007] Page 2 of 28The need for improved mobility solutions remains, particularly for systems that combine lightweight actuators with advanced sensor technology to provide precise and responsive support. The Active Robotic Knee Brace System and Method for Assisting Mobility in Paraplegic Individuals addresses these deficiencies, offering a promising advancement in the field of assistive mobility technology.

[0008] OBJECTS OF THE INVENTION

[0009] One object of the invention is to provide an active knee brace that integrates a combination of two inertial measurement units (IMUs), two-channel electromyography (EMG) sensors, and a rotary encoder to accurately detect user intent and analyze gait patterns, thereby enhancing the precision and responsiveness of the assistance provided.

[0010] Another object of the invention is to offer a lightweight yet high-torque electric actuator system that delivers dynamic assistance, ensuring a more efficient and natural user experience by improving mobility and mitigating the physiological effects of prolonged immobility.

[0011] Yet another object of the invention is to incorporate advanced sensor fusion and control systems that dynamically adapt to varying mobility needs, allowing the knee brace to provide real-time responsiveness and minimize the user's physical exertion while promoting safe and effective mobility.

[0012] A further object of the invention is to address the limitations of existing powered orthoses, such as bulkiness, lack of responsiveness, and limited adaptability, by providing a superior solution that is lightweight, highly adaptive, and efficient, thereby improving the quality of life for users.

[0013] An additional object of the invention is to utilize a high-speed microcontroller capable of real-time operation, maintaining sensor reading sampling rates at 2000Hz, and ensuring overall system latency remains within a range of 5 to 20ms, thus enhancing the system's responsiveness and accuracy.

[0014] Page 3 of 28Another object of the invention is to employ a BLDC motor with a 64:1 gear ratio achieved using a planetary gearbox, providing torque in the range of 20Nm to 40Nm, and ensuring good back drivability and low cogging torque for smooth and natural knee joint motion.

[0015] Yet another object of the invention is to implement a robust power management system using a Lithium polymer battery pack with a 48V DC power supply, incorporating buck-boost converters, heat dissipation, overheating protection, and a battery management system to ensure reliable and efficient operation.

[0016] A further object of the invention is to design the structure of the knee brace using high-strength, lightweight polymers that are resistant to environmental conditions, such as moisture and UV light, and are anticorrosive, providing durability and comfort for the user.

[0017] An additional object of the invention is to enhance user comfort and support through the use of Velcro straps with a width of 5cm and a thickness of 1 to 2mm, ensuring sufficient strength and comfort while allowing for proper motion transfer and offloading of knee load to the robotic structure.

[0018] Another object of the invention is to provide a method for implementing intent detection using advanced signal processing in the EMG sensor module, with a sampling rate of 2000Hz, enabling the system to predict user movement intentions with high accuracy and facilitate a feedforward control system.

[0019] SUMMARY OF THE INVENTION

[0020] The present invention is described in the following sections by various embodiments. However, it should be understood that the invention can be implemented in various forms and is not limited to the specific embodiment provided herein. In the context of the present disclosure, it should be understood that the described embodiments in this section are put forth for illustrative purposes only. Those skilled in the art will appreciate Page 4 of 28that various modifications, adaptations, and alternative designs may be employed without departing from the scope and spirit of the invention. Accordingly, the present invention should not be limited to the specific embodiments illustrated herein, but rather should be construed according to the claims and description that follow.

[0021] Embodiments of the present invention provide an active robotic knee brace system for assisting mobility in paraplegic individuals. The system comprises a plurality of inertial measurement units (IMUs), including a first IMU sensor module and a second IMU sensor module, configured to capture real-time motion data of a user's leg. Additionally, the system includes a plurality of electromyography (EMG) sensors, comprising a first EMG signal module and a second EMG signal module, designed to detect muscular activity of the user. A rotary type absolute encoder is configured to provide angular position feedback of the knee joint. The system further comprises a control unit and power source compartment that processes data from the IMUs, EMG sensors, and encoder to generate torque commands. An electric actuator, coupled with a gearbox, is configured to apply force to assist knee joint motion. The system also includes an upper part attached to the thigh and a lower part attached to the calf, connected by adjustable attachment mechanisms for secure fitting. The control unit is configured to utilize sensor fusion to dynamically adapt to the user's gait cycle, providing real-time responsive support.

[0022] The advantages offered by this embodiment include enhanced mobility for paraplegic individuals through the integration of advanced sensor arrays and a lightweight actuator. The system's ability to dynamically adapt to the user's gait cycle ensures a more natural and efficient gait, reducing physical exertion and promoting safe mobility. The lightweight design and intelligent control system make it a practical tool for improving the quality of life for users.

[0023] Page 5 of 28In accordance with an embodiment of the present invention, the electric actuator is a brushless DC motor with a 64:1 gear ratio, providing torque in the range of 20 Nm to 40 Nm. This configuration allows the actuator to deliver high torque while maintaining a lightweight profile, essential for dynamic assistance in knee joint motion.

[0024] In accordance with another embodiment of the present invention, the control unit and power source compartment houses a high-speed microcontroller board running a real-time operating system (RTOS) to maintain sensor reading sampling rates at 2000 Hz. This ensures precise and timely processing of sensor data, enabling the system to respond swiftly to changes in the user's gait.

[0025] In accordance with yet another embodiment of the present invention, the EMG sensor modules include advanced signal processing capabilities with an instrumentation amplifier and filters to accurately detect user intent. This feature enhances the system's ability to interpret muscular signals, contributing to the accurate generation of torque commands.

[0026] In accordance with a further embodiment of the present invention, the IMU sensor modules provide 9 degrees of freedom information, including acceleration, position, and angle of rotation in the x, y, and z axes. This comprehensive data collection allows for a detailed analysis of the user's motion, facilitating precise control of the knee brace.

[0027] In accordance with an additional embodiment of the present invention, the rotary type absolute encoder is positioned at the knee joint's rotational axis to aid in understanding the user's gait cycle. This positioning ensures accurate feedback on the knee joint's angular position, crucial for effective assistance.

[0028] In accordance with another embodiment of the present invention, the upper part and lower part are made from high-strength, lightweight polymer materials resistant to environmental conditions. This material choice

[0029] Page 6 of 28ensures durability and comfort, making the knee brace suitable for various environments.

[0030] In accordance with a further embodiment of the present invention, the system is powered by a lithium polymer battery pack providing 48V DC power, with buck-boost converters and a battery management system for reliable power supply. This power configuration supports the system's high-performance requirements while ensuring safety and efficiency.

[0031] In accordance with yet another embodiment of the present invention, the attachment mechanisms include Velcro straps for easy attachment and secure fitting to the user's leg. This design allows for quick adjustments and a comfortable fit, enhancing user convenience.

[0032] The invention represents a significant advancement in powered orthotic devices, offering a highly adaptive and efficient knee brace that enhances mobility while mitigating the physiological consequences of immobility.

[0033] BRIEF DESCRIPTION OF DRAWINGS

[0034] In order to facilitate a comprehensive understanding of the detailed features of the present invention, a more specific description of the invention, briefly summarized above, may have been referenced through various embodiments, some of which are depicted in the accompanying drawings. It should be emphasized, however, that the provided drawings merely exemplify typical embodiments of the present invention and should not be construed as limiting its scope, as the invention may encompass other equally efficacious embodiments.

[0035] These and additional features, advantages, and benefits of the present invention will become apparent by consulting the following textual illustration, wherein similar reference numerals denote similar components throughout the various views.

[0036] Page 7 of 28Fig. 1 illustrates a cross-sectional view of the device, showing the EMG signal module, IMU sensor module, control unit and power source compartment, upper part, rotary type absolute encoder, electric motor with gearbox, and attachment mechanisms to the lower leg with tightening possibilities, in accordance with an embodiment of the present invention;

[0037] Fig. 2 illustrates a top view of the device, depicting the EMG signal module, IMU sensor module, control unit and power source compartment, upper part, rotary type absolute encoder, electric motor with gearbox, and attachment mechanisms to the lower leg with tightening possibilities, in accordance with an embodiment of the present invention;

[0038] Fig. 3 illustrates a side view of the device, featuring the EMG signal module, IMU sensor module, control unit and power source compartment, upper part, rotary type absolute encoder, electric motor with gearbox, and attachment mechanisms to the lower leg with tightening possibilities, in accordance with an embodiment of the present invention;

[0039] Fig. 4 illustrates a front view of the device, highlighting the EMG signal module, IMU sensor module, control unit and power source compartment, upper part, rotary type absolute encoder, electric motor with gearbox, and attachment mechanisms to the lower leg with tightening possibilities, in accordance with an embodiment of the present invention.

[0040] DETAILED DESCRIPTION OF THE INVENTION

[0041] The present invention is subsequently described herein using various embodiments with reference to the accompanying drawing, wherein the reference numerals utilized in the accompanying drawing correspond to the similar elements throughout the description. While the present invention is illustratively described herein by way of example using embodiments and accompanying drawings, those skilled in the art will acknowledge that the invention is not limited to the described embodiments or drawings and is not intended to represent the scale of the different components. Furthermore,

[0042] Page 8 of 28certain components that may constitute a part of the invention might not be depicted in specific figures for the purpose of simplified illustration, and such omissions do not restrict the outlined embodiments in any manner. It should be comprehended that the drawings and the detailed description provided are not intended to limit the invention to the particular disclosed form, but instead, the invention is intended to encompass all modifications, equivalents, and alternatives falling within the scope of the present invention as defined by the appended claim. Throughout this description, the term 'may' is used in a permissive sense, indicating the potential to, rather than in a mandatory sense, indicating a requirement. Additionally, the words 'a' or 'an' signify at least one, and the word 'plurality' signifies 'one or more' unless otherwise specified. Moreover, the terminology and phraseology employed herein are solely for descriptive purposes and should not be construed as limiting in scope. Terms such as 'including', 'comprising', 'having', 'containing', or 'involving', and their variations, are intended to be broad and encompass the listed subject matter thereafter, as well as equivalents and additional subject matter not explicitly mentioned, and should not be interpreted as excluding other additives, components, integers, or steps. Similarly, the term 'comprising' is considered synonymous with the terms 'including' or 'containing' for applicable legal purposes.

[0043] The present invention pertains to an active robotic knee brace system designed to assist mobility in individuals with paraplegia and other conditions affecting lower limb function. This innovative system integrates advanced sensor arrays, including two inertial measurement units (IMUs), two-channel electromyography (EMG) sensors, and a rotary encoder, to accurately detect user intent and analyze gait patterns. The system processes this sensor data to generate torque commands for an electric actuator, which is lightweight yet capable of delivering high torque, thereby providing dynamic assistance to the knee joint. This approach ensures a

[0044] Page 9 of 28more efficient and natural user experience, enhancing mobility and mitigating the physiological effects of prolonged immobility.

[0045] The invention's key novelty lies in its ability to dynamically adapt to the user's gait cycle through sensor fusion, offering real-time responsive support. The IMUs provide nine degrees of freedom information, capturing acceleration, position, and angle of rotation in the x, y, and z axes. The EMG sensors, equipped with advanced signal processing capabilities, detect muscular activity to implement a feedforward control system. The rotary encoder, positioned at the knee joint's rotational axis, aids in understanding the user's gait cycle, contributing to the feedback control system. The control unit, housed within a power source compartment, processes the data from these sensors to generate appropriate torque commands for the electric actuator, which is a brushless DC motor with a 64:1 gear ratio, providing torque in the range of 20 Nm to 40 Nm.

[0046] The system's design emphasizes user comfort and ease of use, featuring an upper part attached to the thigh and a lower part attached to the calf, both made from high-strength, lightweight polymer materials resistant to environmental conditions. Adjustable attachment mechanisms, including Velcro straps, ensure a secure fit. The entire system is powered by a lithium polymer battery pack providing 48V DC power, with buck-boost converters and a battery management system for reliable power supply. This invention represents a significant advancement in powered orthotic devices, offering a practical and effective tool for improving the quality of life for users by enhancing mobility and reducing the burden of immobility.

[0047] Various modifications to these embodiments are evident to those skilled in the art based on the description. The principles associated with the various embodiments described herein can be applied to additional embodiments. Consequently, the description is not intended to be limited to the embodiments but aims to provide the broadest scope consistent with the principles and the innovative and inventive features disclosed or Page 10 of 28suggested herein. Therefore, the invention is expected to encompass all other such alternatives, modifications, and variations falling within the scope of the present invention.

[0048] Figure 1 illustrates a cross-sectional view of the active robotic knee brace system, highlighting the integration of various components essential for its operation. The system comprises an upper part (4) and a lower part (9), both constructed from high-strength, lightweight polymer materials that are resistant to environmental conditions such as moisture and UV light. These materials are selected for their anti-corrosive properties, ensuring durability and longevity of the device. The upper part (4) is designed to attach to the thigh, while the lower part (9) is secured to the calf, providing a stable and comfortable fit for the user.

[0049] The attachment mechanism (10, 11) to the lower leg includes Velcro straps, which are 5 cm wide and 1 to 2 mm thick, offering sufficient strength and comfort. These straps feature a hook on one side and a loop on the other, allowing for easy adjustment and secure fastening. This mechanism ensures that the brace remains in place during various activities, such as walking, sitting, and standing, while also facilitating the offloading of knee stress to the robotic structure, thereby reducing knee pain.

[0050] The system incorporates an EMG signal module (1 , 8) and an IMU sensor module (2, 7) to detect user intent and analyze gait patterns. The EMG sensors are equipped with advanced signal processing capabilities, including an instrumentation amplifier, bandpass filter, and notch filter, to accurately capture muscular activity. The IMU sensors provide nine degrees of freedom information, capturing acceleration, position, and angle of rotation in the x, y, and z axes. These sensors work in conjunction with a rotary type absolute encoder (5) positioned at the knee joint's rotational axis, which aids in understanding the user's gait cycle and contributes to the feedback control system.

[0051] Page 11 of 28In one embodiment of the invention, the control unit and power source compartment (3) houses a high-speed microcontroller board capable of implementing real-time operating systems. This microcontroller processes data from the sensors, generating torque commands for the electric motor with a gearbox (6). The motor, a brushless DC motor with a 64:1 gear ratio, provides torque in the range of 20 Nm to 40 Nm, ensuring smooth and natural knee joint movement. The motor's design includes a field-oriented control (FOC) system for precise position and torque control, enhancing the system's responsiveness to user movements.

[0052] Additionally, the system is powered by a lithium polymer battery pack providing 48V DC power. The power management system includes buckboost converters to lower voltages for different electronic components, along with heat dissipation and overheating protection circuits. A battery management system is integrated to prevent over-discharge, ensuring reliable and safe operation. This power configuration supports the system's high-speed operation, maintaining sensor sampling rates and overall system latency within optimal ranges for real-time responsiveness.

[0053] In accordance with yet another embodiment, the system's hybrid control system utilizes sensor fusion to achieve dynamic adaptability. The EMG sensors detect muscular potential for feedforward control, while the IMU sensors and encoder provide feedback control, allowing the system to adjust to the user's gait cycle in real-time. This integration of advanced sensor arrays and intelligent control algorithms ensures that the knee brace system offers a superior solution for individuals seeking to regain mobility, enhancing their quality of life by providing efficient and responsive assistance.

[0054] Figure 2 illustrates a top view of the active robotic knee brace system, showcasing the arrangement and integration of its key components. The EMG signal modules (1 , 8) are strategically positioned to capture muscular activity, providing critical data for the system's feedforward control Page 12 of 28mechanism. The IMU sensor modules (2, 7) are placed to gather comprehensive motion data, including acceleration, position, and rotational angles, which are essential for the feedback control system. These sensors are integral to the system's ability to detect user intent and adapt to varying mobility needs.

[0055] The control unit and power source compartment (3) is centrally located, housing the high-speed microcontroller board responsible for processing sensor data and executing control algorithms. This compartment is designed to protect the electronic components from environmental factors while ensuring efficient heat dissipation. The rotary type absolute encoder (5) is aligned with the knee joint's rotational axis, providing precise measurements of knee angle and contributing to the system's ability to predict user movement with high accuracy.

[0056] In one embodiment of the invention, the electric motor with a gearbox (6) is configured to deliver the necessary torque for knee joint assistance. The motor's integration with the control unit allows for seamless communication via a CAN bus, ensuring that torque commands are executed promptly and accurately. The motor's design, featuring a brushless DC configuration and a 64:1 gear ratio, provides the required torque range while maintaining low cogging torque for smooth operation.

[0057] The attachment mechanisms (10, 11) to the lower leg are designed for ease of use and comfort, utilizing Velcro straps for secure fastening. These mechanisms ensure that the brace remains stable during various activities, facilitating effective offloading of knee stress and reducing pain. The materials used for these components are selected for their durability and resistance to environmental conditions, ensuring long-term reliability of the system.

[0058] In accordance with yet another embodiment, the system's power management strategy includes a lithium polymer battery pack providing 48V

[0059] Page 13 of 28DC power, with buck-boost converters to regulate voltages for different components. This configuration supports the high-speed operation of the microcontroller and sensors, maintaining optimal system latency for realtime responsiveness. The battery management system ensures safe operation by preventing over-discharge and managing heat dissipation effectively.

[0060] The hybrid control system, achieved through sensor fusion, allows the knee brace to dynamically adapt to the user's gait cycle. The EMG sensors provide data for feedforward control, while the IMU sensors and encoder contribute to feedback control, enabling the system to offer precise and responsive assistance. This integration of advanced sensor technology and intelligent control algorithms positions the invention as a superior solution for enhancing mobility in individuals with lower limb impairments.

[0061] Figure 3 illustrates a side view of the active robotic knee brace system, emphasizing the spatial arrangement and interaction of its components. The EMG signal module (1 , 8) is positioned to effectively capture the user's muscular activity, which is crucial for the system's feedforward control mechanism. The IMU sensor module (2, 7) is strategically placed to gather comprehensive motion data, including acceleration, position, and rotational angles, which are essential for the feedback control system. These sensors are integral to the system's ability to detect user intent and adapt to varying mobility needs.

[0062] The control unit and power source compartment (3) is centrally located, housing the high-speed microcontroller board responsible for processing sensor data and executing control algorithms. This compartment is designed to protect the electronic components from environmental factors while ensuring efficient heat dissipation. The rotary type absolute encoder (5) is aligned with the knee joint's rotational axis, providing precise measurements of knee angle and contributing to the system's ability to predict user movement with high accuracy.

[0063] Page 14 of 28In one embodiment of the invention, the electric motor with a gearbox (6) is configured to deliver the necessary torque for knee joint assistance. The motor's integration with the control unit allows for seamless communication via a CAN bus, ensuring that torque commands are executed promptly and accurately. The motor's design, featuring a brushless DC configuration and a 64:1 gear ratio, provides the required torque range while maintaining low cogging torque for smooth operation.

[0064] The attachment mechanisms (10, 11) to the lower leg are designed for ease of use and comfort, utilizing Velcro straps for secure fastening. These mechanisms ensure that the brace remains stable during various activities, facilitating effective offloading of knee stress and reducing pain. The materials used for these components are selected for their durability and resistance to environmental conditions, ensuring long-term reliability of the system.

[0065] In accordance with yet another embodiment, the system's power management strategy includes a lithium polymer battery pack providing 48V DC power, with buck-boost converters to regulate voltages for different components. This configuration supports the high-speed operation of the microcontroller and sensors, maintaining optimal system latency for realtime responsiveness. The battery management system ensures safe operation by preventing over-discharge and managing heat dissipation effectively.

[0066] The hybrid control system, achieved through sensor fusion, allows the knee brace to dynamically adapt to the user's gait cycle. The EMG sensors provide data for feedforward control, while the IMU sensors and encoder contribute to feedback control, enabling the system to offer precise and responsive assistance. This integration of advanced sensor technology and intelligent control algorithms positions the invention as a superior solution for enhancing mobility in individuals with lower limb impairments.

[0067] Page 15 of 28Figure 4 illustrates a front view of the active robotic knee brace system, highlighting the arrangement and integration of its key components. The EMG signal modules (1, 8) are strategically positioned to capture muscular activity, providing critical data for the system's feedforward control mechanism. The IMU sensor modules (2, 7) are placed to gather comprehensive motion data, including acceleration, position, and rotational angles, which are essential for the feedback control system. These sensors are integral to the system's ability to detect user intent and adapt to varying mobility needs.

[0068] The control unit and power source compartment (3) is centrally located, housing the high-speed microcontroller board responsible for processing sensor data and executing control algorithms. This compartment is designed to protect the electronic components from environmental factors while ensuring efficient heat dissipation. The rotary type absolute encoder (5) is aligned with the knee joint's rotational axis, providing precise measurements of knee angle and contributing to the system's ability to predict user movement with high accuracy.

[0069] In one embodiment of the invention, the electric motor with a gearbox (6) is configured to deliver the necessary torque for knee joint assistance. The motor's integration with the control unit allows for seamless communication via a CAN bus, ensuring that torque commands are executed promptly and accurately. The motor's design, featuring a brushless DC configuration and a 64:1 gear ratio, provides the required torque range while maintaining low cogging torque for smooth operation.

[0070] The attachment mechanisms (10, 11) to the lower leg are designed for ease of use and comfort, utilizing Velcro straps for secure fastening. These mechanisms ensure that the brace remains stable during various activities, facilitating effective offloading of knee stress and reducing pain. The materials used for these components are selected for their durability

[0071] Page 16 of 28and resistance to environmental conditions, ensuring long-term reliability of the system.

[0072] In accordance with yet another embodiment, the system's power management strategy includes a lithium polymer battery pack providing 48V DC power, with buck-boost converters to regulate voltages for different components. This configuration supports the high-speed operation of the microcontroller and sensors, maintaining optimal system latency for realtime responsiveness. The battery management system ensures safe operation by preventing over-discharge and managing heat dissipation effectively.

[0073] The hybrid control system, achieved through sensor fusion, allows the knee brace to dynamically adapt to the user's gait cycle. The EMG sensors provide data for feedforward control, while the IMU sensors and encoder contribute to feedback control, enabling the system to offer precise and responsive assistance. This integration of advanced sensor technology and intelligent control algorithms positions the invention as a superior solution for enhancing mobility in individuals with lower limb impairments.

[0074] The method for assisting mobility in paraplegic individuals using the active robotic knee brace system involves capturing real-time motion data of a user's leg through the plurality of inertial measurement units (IMUs) and detecting muscular activity using the electromyography (EMG) sensors. The rotary type absolute encoder provides angular position feedback of the knee joint, which is crucial for the feedback control system. The control unit processes the data from the IMUs, EMG sensors, and encoder to generate torque commands, which are then executed by the electric actuator coupled with a gearbox to apply the necessary force for knee joint assistance. The adjustable attachment mechanisms ensure that the knee brace is securely fitted to the user's leg, facilitating effective offloading of knee stress and reducing pain.

[0075] Page 17 of 28In an embodiment of the present invention, the system's adaptability is further enhanced by the integration of a hybrid control system that utilizes sensor fusion. The EMG sensors detect muscular potential for feedforward control, while the IMU sensors and encoder provide feedback control, allowing the system to dynamically adjust to the user's gait cycle in realtime. This ensures that the knee brace system offers precise and responsive assistance, adapting to the user's mobility needs and enhancing their quality of life.

[0076] Possible variations and modifications of the invention include the use of alternative sensor technologies or configurations to further improve the system's responsiveness and adaptability. For instance, additional sensors could be integrated to provide more comprehensive data on the user's movement and physiological signals. Another embodiment of the present invention may involve the use of different materials for the brace components to enhance comfort and durability, or the implementation of advanced control algorithms to optimize the system's performance.

[0077] The invention's benefits are underscored by its lightweight design, advanced sensor integration, and intelligent control system, which collectively enable a more natural and efficient gait for users. The technical features, such as the high-speed microcontroller, brushless DC motor with a 64:1 gear ratio, and robust power management system, contribute to the system's ability to provide real-time responsive support, thereby improving mobility and mitigating the physiological effects of prolonged immobility. This innovative approach offers a practical and effective solution for individuals seeking to regain mobility, ultimately enhancing their quality of life.

[0078] Various modifications to these embodiments are evident to those skilled in the art based on the description and accompanying drawings. The principles associated with the various embodiments described herein can be applied to additional embodiments. Consequently, the description is not Page 18 of 28intended to be limited to the embodiments shown in conjunction with the accompanying drawings but aims to provide the broadest scope consistent with the principles and the innovative and inventive features disclosed or suggested herein. Therefore, the invention is expected to encompass all other such alternatives, modifications, and variations falling within the scope of the present invention and the appended claims.

[0079] Page 19 of 28

Claims

CLAIMS1. An active robotic knee brace system for assisting mobility in paraplegic individuals, the system comprising:I. a plurality of inertial measurement units (IMUs) including a first IMU sensor module (2) and a second IMU sensor module (7), configured to capture real-time motion data of a user's leg; II. a plurality of electromyography (EMG) sensors including a first EMG signal module (1) and a second EMG signal module (8), configured to detect muscular activity of the user;III. a rotary type absolute encoder (5) configured to provide angular position feedback of the knee joint;IV. a control unit and power source compartment (3) configured to process data from the IMUs, EMG sensors, and encoder to generate torque commands;V. an electric actuator (6) coupled with a gearbox, configured to apply force to assist knee joint motion;VI. an upper part (4) attached to the thigh and a lower part (9) attached to the calf, connected by adjustable attachment mechanisms (10, 11) for secure fitting;wherein the control unit is configured to utilize sensor fusion to dynamically adapt to the user's gait cycle, providing real-time responsive support.

2. The active robotic knee brace system as claimed in claim 1 , wherein the electric actuator (6) is a brushless DC motor with a 64:1 gear ratio, providing torque in the range of 20 Nm to 40 Nm.

3. The active robotic knee brace system as claimed in claim 1 , wherein the control unit and power source compartment (3) houses a high-speedPage 20 of 28microcontroller board running a real-time operating system (RTOS) to maintain sensor reading sampling rates at 2000 Hz.

4. The active robotic knee brace system as claimed in claim 1 , wherein the EMG sensor modules (1, 8) include advanced signal processing capabilities with an instrumentation amplifier and filters to accurately detect user intent.

5. The active robotic knee brace system as claimed in claim 1 , wherein the IMU sensor modules (2, 7) provide 9 degrees of freedom information, including acceleration, position, and angle of rotation in the x, y, and z axes.

6. The active robotic knee brace system as claimed in claim 1 , wherein the rotary type absolute encoder (5) is positioned at the knee joint's rotational axis to aid in understanding the user's gait cycle.

7. The active robotic knee brace system as claimed in claim 1 , wherein the upper part (4) and lower part (9) are made from high-strength, lightweight polymer materials resistant to environmental conditions.

8. The active robotic knee brace system as claimed in claim 1 , wherein the system is powered by a lithium polymer battery pack providing 48V DC power, with buck-boost converters and a battery management system for reliable power supply.

9. The active robotic knee brace system as claimed in claim 1 , wherein the attachment mechanisms (10, 11) include Velcro straps for easy attachment and secure fitting to the user's leg.

10. A method for assisting mobility in paraplegic individuals using an active robotic knee brace system, the method comprising:I. capturing real-time motion data of a user's leg using a plurality of inertial measurement units (IMUs);Page 21 of 28II. detecting muscular activity of the user using a plurality of electromyography (EMG) sensors;III. providing angular position feedback of the knee joint using a rotary type absolute encoder;IV. processing data from the IMUs, EMG sensors, and encoder using a control unit to generate torque commands;V. applying force to assist knee joint motion using an electric actuator coupled with a gearbox;VI. securing the knee brace to the user's leg using adjustable attachment mechanisms;wherein the control unit utilizes sensor fusion to dynamically adapt to the user's gait cycle, providing real-time responsive support.Dated this 07thMarch 2025Signature >Name: - Maulesh H Parikh Applicant’s Agent (IN / PA 4465)Page 22 of 28

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