WO2025116871A1

WO2025116871A1 - Lateral support mechanism for smart walker to prevent side tipping

Info

Publication number: WO2025116871A1
Application number: PCT/TR2024/051433
Authority: WO
Inventors: Nurdan BILGIN; Tolga TUTKAN; Emre NAYIR; Yilmaz Can ER
Original assignee: Ondokuz Mayis Universitesi
Current assignee: Ondokuz Mayis Universitesi
Priority date: 2023-11-30
Filing date: 2024-11-28
Publication date: 2025-06-05
Anticipated expiration: 2026-05-30

Abstract

The invention relates to a lateral support leg mechanism (100) integrated into robotic smart walkers (200) designed for individuals who require physical support for active walking, which automatically deploys through sensors when the possibility of side tipping is detected.

Description

LATERAL SUPPORT MECHANISM FOR SMART WALKER TO PREVENT SIDE TIPPING

Technical Field

The invention relates to a lateral support leg mechanism integrated into robotic smart walkers designed for individuals who require physical support for active walking, which automatically deploys through sensors when the possibility of side tipping is detected.

Background of the Technique

A smart walker is an assistive device designed to help elderly or those with difficulty walking move safely and more comfortably. Typically equipped with electronic and technological features, smart walkers utilize components such as sensors and motors. These features are designed to aid users in maintaining their balance, ensuring stability, and providing support during walking. Smart walkers are also equipped with technologies capable of analyzing data and tracking the user's movements. This allows them to monitor steps, speed, distance, or the amount of pressure applied to the ground, record valuable data, and provide information to healthcare professionals. Smart walkers significantly enhance independence and quality of life for the elderly and those with mobility challenges.

In modern smart walkers currently in use, safety is ensured through methods such as halting motor torque and/or employing a mechanical braking system when navigating roads with positive or negative slopes. Another safety measure in smart walkers is the integration of fall detection and prevention systems based on sensors and algorithms. These systems respond quickly in cases where the user loses balance, aiming to prevent falls effectively. Additionally, smart walkers are equipped with communication tools such as an emergency button or a smartphone application. These features allow users to call for help in case of emergencies. In addition, smart walkers feature partial locking mechanisms to enhance safety. These mechanisms can stabilize specific parts of the walker without restricting the user's freedom of movement, helping maintain balance. This minimizes the risk of slipping or falling in cases where the user loses control. All these measures are implemented to provide a safer experience for users of smart walkers. In traditional walkers, support legs have also been used; however, these legs are fixed and permanently attached to the walker. Another type of support leg used in walkers is manually adjustable to prevent tipping or movement on inclines. The disadvantage of fixed legs is that they may get caught on surrounding objects, while the drawback of manually adjustable legs is that they rely on the user's physical and cognitive abilities. Both types of support legs could negatively affect the user's comfort and increase the risk of falling.

Many studies have been conducted, and new fall prevention systems have been developed to make the use of smart walkers safer. One of these studies is the invention described in patent application CN111658452A. The invention relates to the field of nursing technology, specifically a fall prevention device designed for Parkinson's disease patients. The current invention aims to address the issue in the existing medical process where crutches, wall supports, or simple assistive devices are frequently used to help Parkinson's patients by designing a fall-prevention device specifically for them. The invention is equipped with safety features, including a spring-mounted piston support element fixed at a specific angle to prevent forward and backward tipping, as well as a lateral protective wheel positioned fixedly to prevent the possibility of side tipping.

Another study is the invention described in patent application CN106726375A, which relates to a rehabilitation aid, specifically a walker designed to prevent tipping. The aim of the current invention is to provide a fall-preventing walker that can generate an effective resistance moment to prevent tipping and support the user in avoiding falls. The invention aims to enhance fall assistance by detecting the force during a fall through pressure sensors in the front and rear support arms, activating the braking system on the wheels, thereby ensuring safety.

Another study is the invention described in patent application CN114053104A. The current invention relates to the technical field of medical devices, specifically a multifunctional orthopedic fall-prevention walking aid. The invention aims to provide a multifunctional fallprevention walking device equipped with fall-prevention components I and II. It solves the walker's tendency to tip over and the lack of a seating area, making it easier for patients to use. The fall-prevention mechanism included in the walker is activated manually through two separate methods. One of these methods is a manual hand-trigger mechanism placed in the position of the user's frequently used hand, while the other is an audio-trigger system positioned at the opposite end of the hand-trigger mechanism. The reason for this positioning is to ensure that the hand trigger is placed where the user is most likely to experience a tendency to fall. In the event of a fall in the opposite direction, the audio trigger is activated with pre-defined commands like "left" or "about to fall," ensuring that the fall-prevention mechanism is engaged.

Another study is the invention described in the utility model patent CN21148554711. This invention continuously measures the tilt of the walker using an inclinometer, and when the walker reaches a tipping threshold, it activates the motor to prevent the walker from falling by using an L-shaped support bar. However, this support does not provide static or stable support. While it can detect the tipping condition of the walker using the inclinometer, it does not detect the user's side tipping.

Another study is the invention described in the utility model patent CN215938201 U. This fallpreventing walking aid, designed to enhance the walking safety of the elderly and individuals with mobility difficulties, includes a support frame. It includes a support frame. The wheels on the front of the support frame are universal wheels. The universal wheels on the rear side are wheels that are restricted to rotate in one direction by a ratchet mechanism. A walking mechanism, the Janssen movement mechanism, is positioned at the lower end of the support frame close to the universal wheel. The walking support is powered by a drive motor, which activates the mechanism. The system, equipped with an infrared sensor, detects the user and assumes they will lean forward and shorten their height during a fall. It then activates the anti-fall system with microcontrollers accordingly.

Another study presents the invention subject to patent application KR2457604B1 . It proposes an adaptive control algorithm that ensures the user's walking is not affected by road conditions by using motor support and sensors placed on the brakes and wheels that measure linear and angular acceleration data. Data from encoders placed on the wheels are used to detect incline. It is also mentioned that a camera, lidar, or ultrasonic sensor can be added for forward vision. No approach is provided for detecting and preventing tipping to the side.

Consequently, the need for a lateral support mechanism for smart walkers, which eliminates the disadvantages present in the current technology and the inadequacy of existing solutions, has made it necessary to develop an improvement in the relevant technical field.

Brief Description of the Invention The present invention relates to a lateral support leg mechanism integrated into smart walkers, a robotic product designed for individuals who need physical support for active walking movement, which meets the requirements mentioned above, eliminates all disadvantages and brings additional advantages, and automatically opens when sensors detect the possibility of tipping to the side.

Based on the state of the art, the invention aims to ensure the safety of the user of the walker by minimizing human influence. The goal of the invention is to ensure the safety of the walker by automatically adjusting it through sensors that detect the potential user's needs, rather than relying on their mobility and/or mental ability to perform actions such as pulling a lever, pressing a button, or speaking certain words.

The invention aims to provide a structure that can not only operate under certain variables, as in existing systems but also adapt to changing environmental conditions (safe stance on ± 15° slope, 120 kg human weight capacity) thanks to the automatic control system.

Another aim of the invention is to enable elderly patients who experience difficulty in walking and concentration and/or mental loss to safely maintain and regain their walking functions thanks to the lateral feet that detect the moment of fall and provide static support.

A further object of the invention is to prevent the walker from rotating on its own axis and/or moving away from the user, in addition to preventing the walker from tipping sideways.

Another aim of the invention is to ensure that the lateral legs are opened and fall prevention is ensured when the decision support system makes an emergency decision thanks to the decision support mechanism based on three different sensor data.

Another aim of the invention is to measure the force and torque in 6 axes and monitor the load distribution change of the user in any axis instantaneously so that when there is a load above a certain threshold value, a fall signal is sent to the lateral foot support mechanism and the lateral feet are triggered to open.

Another aim of the invention is to ensure stability by sending signals to the support mechanism in situations where the distance between the individual's steps, within the scope of the existing walking algorithm, is less or more than the normal step length value or when one foot crosses in front of the other. This is achieved through the regular gait tracking performed by a laser range finder sensor positioned at the user's ankle distance.

Another aim of the invention is to trigger the lateral support mechanism when the threshold values are exceeded by monitoring the acceleration and angular velocity of the walker through an Inertial Measurement Unit (IMU).

A more precise understanding of the structural and characteristic features and all the advantages of the invention will be possible thanks to the figures below and the detailed description written by referencing these figures. Therefore, it is essential to consider these figures and detailed explanations during the evaluation process.

Brief Description of the Figures

To fully understand the structure of the present invention and its advantages, along with additional components, it should be evaluated alongside the figures described below.

Figure-1 : A schematic general view of the smart walker.

Figure-2: A schematic side view of the lateral support leg mechanism.

Figure-3: A schematic front view of the lateral support leg mechanism.

Figure-4: A schematic general view of the lateral support leg mechanism in its open position after triggering.

Reference Numbers

100. Lateral Support Leg Mechanism

110. Force/Torque Sensor

120. Lateral Support Leg Group

121 . Connection Plate

122. Actuator

123. Pin-Socket Support Part

124. Static Support Leg Intermediate Connection Part

125. Static Support Leg

126. Connection Pin

127. Rear Foot Pad

128. Front Foot Pad 130. Handlebar

200. Smart Walker

210. Hub Motor

Detailed Description of the Invention

In this detailed description, the lateral support leg mechanism (100), integrated into robotic smart walkers (200) designed for individuals requiring physical support for active walking movement, is explained solely as an example to enhance understanding. This description is provided without any limiting effect and focuses on the mechanism, which automatically deploys upon detecting the possibility of tipping to the side through sensors.

The smart walker (200) shown in Figure-1 enables individuals who require support to move or walk. The mentioned smart walker (200) includes a lateral support leg group (120) attached to the feet located at the four corners of the smart walker (200), designed to prevent the individual from tipping or falling sideways during movement. In smart walkers (200), the aforementioned lateral support leg mechanism (100) is automatically deployed when the possibility of tipping to the side is detected through sensors. Tipping to the side is detected in two ways: first, when the lateral acceleration acting on the walker exceeds a threshold value, and second, when a change is detected in the user's upright posture or normal walking pattern. The mentioned lateral support leg mechanism (100) is integrated into smart walkers (200), a robotic product designed for individuals requiring physical support for active walking movement. In addition to the stopping and braking system, the mentioned lateral support leg mechanism (100) also includes static support legs (125) at the four corners of the smart walker (200), which automatically operate simultaneously and/or independently to prevent tipping on positive and negative inclines, as well as under variable road conditions. The mentioned lateral support leg mechanism (100) is positioned at the upper part of the smart walker (200), with a force/torque sensor (110) placed between the handlebar (130), which is the user's only direct connection to the walker, and the main frame. The mentioned force/torque sensor (110) continuously measures force and torque on six axes, allowing realtime tracking of changes in the user's load distribution across the axes. Based on this data, when the loading exceeds certain threshold values, a signal is sent to the lateral support leg group (120), triggering the deployment of the static support leg (125).

The lateral support leg group (120) shown in Figure-2 includes static support legs (125) that are automatically triggered to prevent tipping to the side and to ensure that the smart walker (200) remains static, stable, and steady in emergencies. The mentioned lateral support leg mechanism (100) includes a decision support mechanism based on three different sensor data: the force/torque sensor (110), the laser range finder sensor, and the IMU (Inertial Measurement Unit). The laser range finder sensor performs regular gait tracking at the user's ankle distance. In cases where the distance between the individual's steps in the current walking algorithm is either less than or greater than the normal step length or when one foot crosses in front of the other, the system sends a signal to the lateral support leg group (120) for stability. The mentioned IMU (Inertial Measurement Unit) tracks the acceleration and angular velocity of the smart walker (200), triggering the deployment of the lateral support leg group (120) when the set threshold values are exceeded. When the decision support system makes an emergency decision, the static support legs (125) are deployed. The front static support legs (125) of the mentioned smart walker (200), which are connected to the front two legs, have a front foot pad (128) positioned at the bottom where the static support leg (125) makes contact with the ground. This pad prevents the static support leg from slipping on the ground when activated. The rear static support legs (125) of the mentioned smart walker (200), which are connected to the rear two legs, have a rear foot pad (127) positioned at the bottom where the static support leg (125) makes contact with the ground. This pad prevents the static support leg from slipping on the ground when activated. The upper part of the mentioned static support leg (125) is connected in a movable manner to the static support leg intermediate connection part (124) via a hinged connection. The mentioned static support leg intermediate connection part (124) is connected in a movable manner to the pin-socket support part (123) via the connection pin (126), as shown in Figure-3. The actuator (122) is positioned at the end of the mentioned pin-socket support part (123). The connection plate (121 ) provides the connection between the actuator (122), the pin-socket support part (123) and the static support leg (125).

The force/torque sensor (110) located on the handlebar (130) of the smart walker (200), which the user directly interacts with for driving, detects the user's unbalanced load distribution outside the normal driving algorithm, and/or the existing tilt sensor in the hub motor (210) of the smart walker (200) transmits a pre-fall action to the system. Then, the lateral support leg mechanism (100) is triggered, and the static support legs (125) are deployed depending on the direction of the fall. After the detected lateral tipping movement, the actuator (122) is activated and sequentially triggers the pin-socket support part (123), the static support leg intermediate connection part (124), and finally, the static support leg (125) at a speed of 70 mm/s. This action ensures that the rear foot pad (127) and the front foot pad (128) make contact with the ground, providing lateral support to prevent the smart walker (200) from tipping over.

Claims

1. The invention is a lateral support leg mechanism (100) integrated into smart walkers (200), which are robotic products designed for individuals requiring physical support for active walking, characterized by:

- Lateral support leg group (120) connected to the feet at the four corners of the smart walker (200), which automatically opens when the possibility of tipping to the side is detected by a force/torque sensor (110), a laser range finder sensor and an IMU (Inertial Measurement Unit) to prevent the person from tipping/falling sideways during movement;

- Force/torque sensor (110) positioned at the top of the smart walker (200) and between the handlebar (130), which is the user's only direct connection to the walker, and the main chassis in order to instantaneously monitor the change in the load distribution of the user in any axis, together with instantaneous force and torque measurement in six axes, and to send a fall signal to trigger the lateral support leg group (120) when there is a load above a certain threshold value;

- Laser range finder sensor that performs regular gait tracking at the user's ankle distance to send stability signals to the lateral support leg group (120) in cases where, within the scope of the individual's current walking algorithm, the distance between steps is less or more than the normal step length, or one foot crosses in front of the other.

- IMU (Inertial Measurement Unit) that monitors the acceleration and angular velocity of the smart walker (200) to trigger the lateral support leg group (125) when set thresholds are exceeded;

- Actuator (122) located at the end of the pin-socket support part (123), which, after detecting lateral tipping motion, is activated to sequentially trigger the pin-socketed support part (123), the static support leg intermediate connection part (124), and finally the static support leg (125), causing the rear foot pad (127) and front foot pad (128) to contact the ground and prevent the smart walker (200) from tipping over.

2. Lateral support leg mechanism (100) in compliance with Claim 1 , characterized by comprising static support legs (125) positioned at the four corners of the smart walker (200), which operate automatically, either simultaneously or independently, in addition to the stopping and braking system, to prevent tipping on positive and negative slopes and varying road conditions.

3. Lateral support leg mechanism (100) in compliance with Claim 1 , characterized by comprising front foot pads (128) positioned at the lower ends of the front static support legs (125) connected to the front two legs of the smart walker (200), to prevent the static support legs (125) from slipping on the ground when deployed.

4. Lateral support leg mechanism (100) in compliance with Claim 1 , characterized by comprising rear foot pads (127) positioned at the lower ends of the rear static support legs (125) connected to the rear two legs of the smart walker (200), to prevent the static support legs (125) from slipping on the ground when deployed.

5. Lateral support leg mechanism (100) in compliance with Claim 1 , characterized by comprising a static support leg intermediate connection part (124) movably connected to the upper part of the static support leg (125) via a hinged connection.

6. Lateral support leg mechanism (100) in compliance with Claim 1 , characterized by comprising a connection pin (126) that links the static support leg intermediate connection part (124) to the pin-socketed support part (123).

7. Lateral support leg mechanism (100) in compliance with Claim 1 , characterized by comprising a pin-socketed support part (123) movably connected to the static support leg intermediate connection part (124).

8. Lateral support leg mechanism (100) in compliance with Claim 1 , characterized by comprising a connection plate (121 ) that links the actuator (122), the pin-socketed support part (123), and the static support leg (125).