Description:FIELD OF THE DISCLOSURE
The present disclosure relates to the field of biomedical and assistive technologies. More particularly, it pertains to a smart prosthetic hand that employs force-sensitive resistor (FSR) sensors for pressure-based control, integrates Internet-of-Things (IoT) capabilities for real-time monitoring and calibration, and includes embedded safety features such as GPS-enabled emergency alerts and smart battery management.
BACKGROUND
Prosthetic hand technologies have evolved over time from simple body-powered systems to advanced myoelectric and hybrid models. While these developments have improved mechanical functionality, significant limitations persist in terms of cost, user adaptability, intuitiveness, and safety. Body-powered prosthetics, though affordable, rely on mechanical harnesses that are physically demanding and offer limited dexterity. Myoelectric prosthetics, which use electromyography (EMG) signals to actuate motors, provide improved movement control but require precise sensor placement, complex calibration, and are highly susceptible to electrical noise. These systems also tend to be expensive and often inaccessible for many users.
Efforts to enhance prosthetic control have led to the development of modular systems, such as the myoelectric prosthetic hand disclosed in one of the conventional arts. While modularity and multi-grip modes are emphasized, such systems remain reliant on EMG signals and lack pressure-based control mechanisms. They also do not address the integration of real-time calibration, user-specific adaptability, or embedded safety features such as GPS-based emergency alerts.
Other conventional arts focus on motorcycle handlebar interaction using optical sensors. However, such systems are not prosthetic devices and are not suitable for amputees, as they neither replicate finger actuation nor include any mechanism for muscle force detection or prosthetic-level grip control. Similarly, wearable fall detection devices described conventionally are limited to motion sensing and are not integrated into functional prosthetic systems capable of actuation or adaptive response. These devices lack tactile sensing, motor control, and real-time connectivity features necessary for a responsive assistive hand.
In academic contexts, systems such as NOHAS explore servo-actuated orthotic devices, but they focus on external support for existing limbs rather than full prosthetic replacements. These systems do not employ pressure-based sensing or offer the degree of control and integration necessary for dynamic tasks such as operating motorcycle clutch or brake levers. They also omit mobile-based calibration, emergency alert mechanisms, or machine learning capabilities.
The prior art in this domain reveals a gap in comprehensive, low-cost, and intuitive prosthetic solutions. Existing devices either prioritize basic functionality or advanced actuation but fail to address the need for smart, pressure-based control, real-time diagnostics, embedded safety, and user-centric adaptability in a single integrated system.
Therefore, there is a pressing need for a prosthetic hand that is not only affordable and functionally robust but also capable of intuitive control through muscle pressure, connected wirelessly for remote configuration and diagnostics, and equipped with built-in safety mechanisms to protect users in real-world environments such as during motorbike operation.
OBJECTS OF THE PRESENT DISCLOSURE
An object of the present disclosure is to provide a smart prosthetic hand that enables intuitive and proportional control through the use of force-sensitive resistor (FSR) sensors, thereby eliminating the need for complex and costly electromyography (EMG) systems.
Another object of the disclosure is to offer a prosthetic solution that simplifies mechanical architecture by utilizing a single servo motor coupled with a gear-driven linkage mechanism, facilitating synchronized movement of multiple fingers with reduced power consumption and weight.
A further object of the disclosure is to enable wireless real-time monitoring, diagnostics, and calibration of the prosthetic hand through integration with Internet-of-Things (IoT) technology and a dedicated mobile application, enhancing adaptability and user convenience.
Yet another object of the disclosure is to incorporate a GPS-enabled emergency alert mechanism that allows users to transmit their real-time location to predefined contacts in distress situations, thereby enhancing personal safety.
It is also an object of the disclosure to provide a battery management system configured to monitor voltage levels and issue low-power warnings, thereby preventing unexpected shutdowns and ensuring continued operation of the prosthetic device.
An additional object of the disclosure is to ensure ergonomic comfort and modular construction of the prosthetic hand, allowing easy disassembly, customization, and reconfiguration for maintenance, portability, or user-specific adjustments.
Still another object of the disclosure is to introduce optional machine learning-based adaptability within the control system, enabling the prosthetic to learn and optimize grip responses based on user-specific pressure patterns over time.
It is also an object of the disclosure to optionally include haptic feedback features to simulate a tactile sense during object interaction, enhancing user awareness and dexterity.
The disclosure further aims to provide a scalable, cost-effective, and user-friendly assistive device that can be applied in a variety of real-world scenarios, including but not limited to motor vehicle control, particularly in operating clutch and brake levers.
SUMMARY
In an aspect, the present disclosure discloses a prosthetic hand system (100) configured to provide responsive finger movement based on mechanical pressure detected from a residual limb. The system comprises a pressure sensor (102), a microcontroller (104) with integrated modules including a signal processing module (104A), a motor control module (104B), a communication interface module (104C), a power monitoring module (104D), and an alert control module (104E). A motor (108) is operably connected to a mechanical linkage (110) housed within a finger assembly (112) to enable coordinated movement of prosthetic fingers.
A wireless communication module (112) is connected to the microcontroller (104) for real-time data exchange with an external device (106). A power supply (114) is coupled with the power monitoring module (104D) for continuous voltage tracking. A location tracking module (116) enables position-based alerts via the alert control module (104E). Additionally, a feedback unit (118) comprising an actuator (120) is disposed on the inner surface of the system (100) to deliver tactile feedback to the user.
The system (100) features a modular design with intra-finger linkage integration and combined sensory, control, and communication elements to support smart assistive and rehabilitative functionality.
The disclosed method (200) enables the automatic control of a prosthetic hand in response to pressure applied by a user's residual limb. The process begins when a pressure sensor detects mechanical input, such as a flexing or pressing motion. This mechanical pressure is converted into an electrical signal, which is processed by a microcontroller. The microcontroller generates a corresponding actuation command that activates a motor, which drives a mechanical linkage to move the prosthetic fingers in a coordinated manner.
In parallel, the system (100) monitors its power supply status through a voltage detection circuit. If a predefined low-power condition is detected, the microcontroller can trigger a location signal through an integrated tracking module, transmitting coordinates to an external device via a wireless interface. Additionally, a feedback unit provides tactile sensations to the user, enhancing the user experience and operational awareness.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects, features, and advantages of the embodiment will be apparent from the following description when read with reference to the accompanying drawings. In the drawings, wherein like reference numerals denote corresponding parts throughout the several views:
Referring to Figure 1A-1C, shows schematic views of a prosthetic hand system (100), in accordance with an embodiment of a present disclosure;
Referring to Figure 1D, shows block representation of various components of the prosthetic hand system (100), in accordance with an embodiment of a present disclosure; and
Referring to Figure 2, shows a flowchart depicting steps of a method (200) for controlling the prosthetic hand system (100), in accordance with another embodiment of the present disclosure.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following discussion provides many example embodiments of the inventive subject matter. Although each embodiment represents a single combination of inventive elements, the inventive subject matter is considered to include all possible combinations of the disclosed elements. Thus, if one embodiment comprises elements A, B, and C, and a second embodiment comprises elements B and D, then the inventive subject matter is also considered to include other remaining combinations of A, B, C, or D, even if not explicitly disclosed.
The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
Many modifications will be apparent to those skilled in the art without departing from the scope of the present invention as hereinbefore described with reference to the accompanying drawings.
Throughout this specification and the claims which follow, unless the context requires otherwise, the word “comprise”, and variations such as “comprises” and “comprising”, will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.
As used herein, the singular forms “a”, “an”, “the” include plural referents unless the context clearly dictates otherwise. Further, the terms “like”, “as such”, “for example”, “including” are meant to introduce examples which further clarify more general subject matter, and should be contemplated for the persons skilled in the art to understand the subject matter.
The present disclosure discloses a prosthetic hand system (100) configured to enable responsive and coordinated movement of prosthetic fingers based on input from a residual limb. The system (100) integrates sensory, mechanical, control, feedback, and communication components within a compact and modular architecture.
The prosthetic hand system (100) includes an external housing formed to resemble a natural hand and forearm profile. The housing supports both internal electronics and mechanical assemblies, and includes an interface to couple with a residual limb. Figure 1A illustrates various external views of the prosthetic hand system (100), including frontal, lateral, and dorsal orientations.
As shown in Figures 1A-1C, the system (100) includes a pressure sensor (102) positioned on an inner surface thereof, adjacent to the residual limb interface. In an embodiment, the sensor (102) includes a force-sensitive resistor configured to detect mechanical pressure exerted by muscular contractions of the residual limb. Exemplary embodiments as follows:
Controlling the Hand: Suppose if one wants to grab a glass of water. The pressure sensor, which is like a sensitive pad inside the prosthetic socket, feels the muscle in one’s arm tightened. When one squeezes one’s muscle, the sensor sends a signal to the prosthetic hand to close one’s fingers around the glass. The harder one squeeze, tighter the grip, so that one can hold it just right.
Setting It Up: The prosthetic needs to learn how one muscles work. During setup, one flex one’s arm muscles lightly and then hard. The sensor records how much pressure one makes each time. This helps the hand know that a soft flex means "pick up a pen gently" and a hard flex means "hold a heavy bottle tightly."
Checking It on One’s Phone: The sensor sends info about one’s muscle movements to a phone app. For instance, doctor can see how often one is using the hand or if one is pressing too hard. They can tweak the settings from the app to make the hand work better for the user.
Keeping One Safe: If the sensor doesn’t feel any muscle movement for a long time, it might mean the hand isn’t fitting right. It can send a message to one’s phone to let one know to check it. Also, if something feels wrong, like too much pressure, it can trigger an alert with one’s location to get help fast.
The electrical signal generated by the sensor (102) is routed to a microcontroller (104) for processing. The microcontroller (104) serves as a central processing unit of the system (100). It comprises a memory configured to store sensor data and execute control logic via integrated submodules including such as but not limited to a Signal Processing Module (104A); a Motor Control Module (104B); Communication Interface Module (104C); Power Monitoring Module (104D); Alert Control Module (104E), as shown in Figure 1E.
The Signal Processing Module (104A) is configured to convert raw pressure sensor signals into interpretable control signals. The Motor Control Module (104B) is configured to translate processed signals into actuation commands for the motor (108) based on predefined grip patterns or finger sequences. The Communication Interface Module (104C) manages wireless data exchange with an external device (106) such as a mobile phone or computing unit. The Power Monitoring Module (104D) monitors the voltage level from the power supply (114) and detects low-power thresholds. The Alert Control Module (104E) initiates alert signals and transmits a location signal when triggered by system events.
The microcontroller (104) may include a pulse-width modulation (PWM) output interface to control motor actuation with variable intensity or speed.
The system (100) involves a microcontroller (with Signal Processing Module 104A) to process muscle pressure signals and a servo motor (controlled by Motor Control Module 104B) to move fingers for grasping, releasing, and holding. Other modules handle communication, power, and alerts. Below are clear, concise exemplary embodiments:
1. Movements: Grasping, Releasing, Holding
Grasping (Picking Up)
• Example: To grab a water bottle, one squeezes one’s arm muscle (1.5N, like pressing a button).
o Signal Processing (Microcontroller): Turns the sensor’s 3V signal into a clean 60% strength number after removing noise.
o Motor Control (Servo Motor): Picks a “wrap-around” grip, sets servo to 90° to close fingers.
o Communication: Sends “1.5N, wrap grip”
o Power Monitoring: Checks battery at 3.7V for servo power.
Releasing (Letting Go)
• Example: To release the bottle, you relax (0.1N, barely pressing).
o Signal Processing: Reads low signal as 0% for “release.”
o Motor Control: Sets servo to 0° to open fingers.
o Communication: Logs “0.1N, released”
o Power Monitoring: Confirms 3.7V battery.
Holding (Keeping Steady)
• Example: To hold a pen, one keeps a steady 0.8N squeeze.
o Signal Processing: Smooths signal to 50% strength.
o Motor Control: Chooses “pinch” grip, holds servo at 45°.
o Communication: Sends “0.8N, pinch”
o Power Monitoring: Watches 3.7V for steady servo use.
2. Pressure Needed
• Grasping: 1–2N (1.5N worked for bottle in 10 tests).
• Releasing: <0.2N (0.1N opened fingers in 10 tests).
• Holding: 0.5–1N (0.8N held pen for 30s in 10 tests). Adjustable during setup for one’s muscles.
3. Signal to Grips
• How It Works: Sensor gives 3V (1.5N), microcontroller cleans it to 60%, maps to:
o <20% (<0.2N): Release
o 20–50% (0.2–1N): Hold
o 50% (>1N): Grasp
• Grip Examples:
1. Wrap-Around: Bottle, all fingers close (1N, 90°, 0.5s).
2. Pinch: Pen, thumb-finger (0.5–1N, 45°, 0.2s).
3. Hook: Bag, fingers bend (0.8–1.2N, 60°, 1s).
4. Release: Fingers open (0.1N, 0°, 0.3s).
4. Power Monitoring
• How: Checks 3.7V battery every second:
o 3.6V: Normal
o 3.4–3.6V: Low
o <3.4V: Critical
• Examples:
1. 3.8V: App shows 80%
2. 3.5V:, “20%, recharge”
3. 3.3V: Sends location, limits servo
4. 4.1V: “90% charged”
5. Alerts
• Low Battery: 3.5V, app alert.
• Too Much Pressure: 3.5N
• No Movement: <0.1N for 30min
• Fall: 4N spike, sends location
• Malfunction: Sensor fails, app error, sends location
• Emergency Button: Pressed, sends “help” with location.
The system (100) uses a battery which is 3.7V rechargeable and may be placed in the forearm section. Wires link the battery to the microcontroller (104) powering the servo motor, sensor, wireless module. The battery supplies power for the microcontroller (104) to process sensor signals (e.g., 1.5N muscle squeeze = 3V signal) and move fingers via the servo. For Instance, when grabbing a cup, the 3.7V battery powers the microcontroller (104) to read a 1.5N signal and close fingers.
SOS System (Emergency Alerts): The microcontroller’s Alert Module (104E) uses GPS to send one’s location to a phone app or contacts via the wireless module. Exemplary alerts as follows:
• Emergency Triggers:
o Pressing an emergency button.
o High pressure (>4N, like a fall)
o No pressure for 1 hour (hand unused)
o Low battery (<3.4V).
o Sensor or motor failure
The SOS system sends a location message (e.g., “Help needed”) and to confirm.
Examples:
1. Press button: Sends “Help at [location]” to family.
2. Fall (4N): Sends “Fall detected,”.
3. No use (1h): Sends “Check hand.”
4. Low battery (3.3V): Sends “Risk of shutdown.”
Single Servo Motor is a small servo motor in the forearm pulls tendons and pulleys to move fingers. The microcontroller (104) sends pulse signals (PWM) to set the motor’s angle (0–180°). E.g., 60% PWM = 90° for grasping.
Examples:
o Grasp Bottle: 60% PWM, servo at 90°, fingers close tightly.
o Release Pen: 10% PWM, servo at 0°, fingers open.
o Hold Key: 50% PWM, servo at 45°, fingers stay steady.
The motor (108) is operably connected to a mechanical linkage (110) housed within a finger assembly (112). The motor (108), controlled by the motor control module (104B), generates rotational movement which is translated into finger articulation by the linkage (110). In one embodiment, the linkage includes at least one tendon and pulley mechanism to simulate natural joint flexion. The placement of linkage (110) within the finger assembly (112) enables fine control of individual or grouped finger movement.
A wireless communication module (112) is operably connected to the communication interface module (104C) and physically positioned adjacent to the microcontroller (104), typically within the forearm section of the system (100). The module (112) transmits operational data, such as grip type, sensor values, and device status, to the external device (106) over a short-range wireless protocol (e.g., Bluetooth or Wi-Fi).
The system (100) includes a power supply (114) housed within the forearm region, supplying energy to all modules. The power supply (114) is electrically coupled to the power monitoring module (104D) for voltage level sensing and threshold-based signaling. In a preferred embodiment, the power supply is a rechargeable lithium-polymer battery with integrated safety circuits.
A location tracking module (116) is operably connected to the alert control module (104E). Upon receiving a trigger input — such as a power failure, manual switch, or abnormal sensor pattern — the system (100) transmits the geographic location data to the external device (106). The location tracking module (116) may use GPS or mobile network triangulation for position acquisition.
The system (100) further includes a feedback unit (118) having one or more actuators (120) mounted on the interior surface of the housing, in direct contact with the residual limb interface area. The actuator (120) receives signals from the microcontroller (104) and generates tactile feedback (e.g., vibration or pressure pulses) corresponding to grip confirmation, overpressure detection, or communication events. This feedback aids the user in proprioceptive awareness and task control.
The microcontroller (104) and motor (108) are positioned within the forearm section of the system (100) to preserve space within the hand section for the mechanical linkage (110). The wireless communication module (112) is also integrated into the forearm area for antenna stability and spatial efficiency. All components are housed in a detachable modular arrangement to allow repair, upgrades, or cleaning.
The prosthetic hand system (100) is constructed in a detachable modular configuration, allowing individual components to be serviced, replaced, or upgraded without compromising the integrity of the whole system. The integration of sensor input, signal processing, mechanical actuation, wireless communication, location tracking, and user feedback into a unified architecture makes the system (100) highly adaptable and suitable for real-world prosthetic applications.
The system (100) has various practical uses. It enables amputees to regain functional hand movement with improved precision and responsiveness. The wireless interface allows remote monitoring and calibration, while the feedback unit supports intuitive user control. The inclusion of a location tracking module enhances safety, particularly for pediatric or elderly users. The system (100) is beneficial in both daily-use prosthetics and advanced rehabilitation settings, offering scalable solutions for users across age groups and functional needs.
As shown in Figure 2, the method (200) for controlling the prosthetic hand system (100) includes the following steps: detecting mechanical pressure using the pressure sensor (102); generating an electrical signal based on the detected input; processing the signal through the microcontroller (104) using the signal processing module (104A) to generate a control signal; driving the motor (108) through the motor control module (104B); converting the motor's rotation into finger movement using the mechanical linkage (110); and, if required, activating the alert control module (104E) when the power monitoring module (104D) detects a low power condition.
The system further transmits data and location information wirelessly to an external device (106) for remote awareness. Simultaneously, tactile feedback is provided to the user through the actuator (120) of the feedback unit (118), completing the functional cycle of the prosthetic hand system (100).
, Claims:We Claim
1. A prosthetic hand system (100) comprising:
a pressure sensor (102) to detect mechanical pressure from a residual limb and generate a corresponding electrical signal;
a microcontroller (104) having a memory to store sensor signal data, the microcontroller (104) comprising:
(a) a signal processing module (104A) to convert the electrical signal into a control signal;
(b) a motor control module (104B) to generate actuation commands based on the control signal;
(c) a communication interface module (104C) to enable wireless data exchange with an external device (106);
(d) a power monitoring module (104D) to measure voltage from a power supply and detect a threshold condition; and
(e) an alert control module (104E) to transmit a location signal upon receiving a trigger input; a motor (108) to receive the actuation commands and produce rotational movement;
a mechanical linkage (110) connected to the motor (108) and adapted to convert rotational movement into coordinated movement of prosthetic fingers within a finger assembly (112); a wireless communication module (112) operably connected to the communication interface module (104C) and adapted to transmit data to the external device (106); a power supply (114) connected to the power monitoring module (104D) to provide electrical energy to the system (100); a location tracking module (116) operably connected to the alert control module (104E) to determine geographic coordinates; and a feedback unit (118) comprising at least one actuator (120) positioned on an interior surface of the system (100) to generate a tactile response based on input from the microcontroller (104); wherein the system (100) enables movement of prosthetic fingers in response to pressure detected from the residual limb and transmits operational and location data to the external device (106).
2. The system (100) as claimed in claim 1, wherein the pressure sensor (102) comprises a force-sensitive resistor.
3. The system (100) as claimed in claim 1, wherein the microcontroller (104) comprises a pulse-width modulation output interface.
4. The system (100) as claimed in claim 1, wherein the mechanical linkage (110) comprises at least one tendon and one pulley to replicate natural finger articulation.
5. The system (100) as claimed in claim 1, wherein the actuator (120) of the feedback unit (118) is mounted on an inner wall of the system (100) and remains in contact with the residual limb.
6. The system (100) as claimed in claim 1, wherein the location tracking module (116) is a GPS-based device configured to provide real-time coordinates.
7. The system (100) as claimed in claim 1, wherein the external device (106) comprises a display unit and user input interface for monitoring and control.
8. The system (100) as claimed in claim 1, wherein the power monitoring module (104D) includes a voltage detection circuit for power threshold detection.
9. The system (100) as claimed in claim 1, wherein the microcontroller (104), motor (108), and wireless communication module (112) are housed within a forearm section of the prosthetic hand system (100).
10. A method (200) for controlling a prosthetic hand system (100), the method (200) comprising:
detecting mechanical pressure from a residual limb using a pressure sensor (102);
generating an electrical signal based on the detected pressure;
processing the signal using a signal processing module (104A) of a microcontroller (104) to produce a control signal;
generating actuation commands using a motor control module (104B) of the microcontroller (104);
driving a motor (108) to actuate a mechanical linkage (110) for coordinated movement of prosthetic fingers in a finger assembly (112);
measuring voltage from a power supply (114) using a power monitoring module (104D);
transmitting a location signal using an alert control module (104E) and a location tracking module (116); and
generating a tactile feedback response using at least one actuator (120) based on an input from the microcontroller (104).