A disabled chair that can make autonomous posture change

Abstract

The present invention relates to a disabled chair that can move autonomously and change posture Simultaneous location determination and mapping will be performed using the SLAM algorithm on the data obtained by sensors (1, 4) based on a predefined target or a determined treatment process. While the chair (2) on which the user is sitting is in motion, the reclining mechanism (5) will make an autonomous posture change. As a result of these activities, which will be carried out under the control of a task computer (7), autonomous movement and posture change capabilities will be provided to the disabled chair.

Description

[0001] A DISABLED CHAIR THAT CAN MAKE AUTONOMOUS POSTURE CHANGE

[0002] Field of the Invention

[0003] The present invention relates to a disabled chair that can move autonomously and change posture.

[0004] State of the art

[0005] With the rapid development of technology day by day, artificial intelligence has begun to become more integrated into our daily lives. As a result of long processes, autonomous vehicles are being actively used in many sectors. Autonomous studies are developing slower than other sectors due to the very low error tolerance rate in the healthcare sector. This situation leads to waste of technical manpower working in health services.

[0006] There are chairs on the market that can be used manually or with a manipulator. These are machines that are guided through an observer or user. Those who are above a certain level of disability or who are not mentally mature enough to use the manipulators cannot use these machines. Posture changes in manual or manipulator chairs are limited and usually lead to a standing position.

[0007] Prior art application numbered CN1 16880514A discloses an intelligent wheelchair control method, an intelligent wheelchair, and a storage medium. In the method, obstacle information is obtained by detecting obstacles in the environment and the behavior of a dynamic obstacle is estimated. In addition, by calculating the probability of collision, the necessity of the wheelchair to avoid the obstacle and the possibility of avoiding it are evaluated. When the environmental risk level is not high, automatic obstacle avoidance is performed. However, in the abovementioned application, features such as mapping, autonomous posture change or moving according to a scenario are not mentioned.

[0008] As a result, due to the abovementioned disadvantages and the insufficiency of the current solutions regarding the subject matter, a development is required to be made in the relevant technical field. Object of the Invention

[0009] The present invention aims to carry out a disabled chair that can move autonomously and change posture. With the chair, autonomous posture changes can be made from the moment the patient enters the hospital without the need for observation and transfer between clinics will be possible. The chair will activate the decision mechanism and move without the need for a manipulator, using the position information or movement scheme received from the user. As soon as the movement starts, it changes the posture with a linear actuator for the user to move in a healthier and safer position.

[0010] The disabled chair, which is the subject of the invention, will be returned to the charging station in the starting position when the patient's treatment process is completed, or the battery level is low. The chair will make itself rechargeable by centering the charging mechanism with image processing.

[0011] Additionally, location information can be monitored on a screen with the GPS module on the chair.

[0012] With the help of the invention, the inefficient use of technical manpower in jobs that require physical strength and time and are not profitable in terms of quantity will be minimized. When its applicability to daily life is ensured, the integration of disabled people into sectors and their quality of life will increase significantly. Autonomization of sectors will minimize occupational accidents caused by human errors.

[0013] The structural and characteristic features of the present invention will be understood clearly by the following drawings and the detailed description made with reference to these drawings.

[0014] Description of the Figures

[0015] Figure 1 is an example of an autonomous ground vehicle performing simultaneous positioning and mapping.

[0016] Figure 2 shows the posture of the reclining mechanism of the disabled chair capable of autonomous posture change, which is the subject of the invention, at an angle between 130°- 150°. Figure 3 is the profile view of the disabled chair that can make autonomous posture changes, which is the subject of the invention.

[0017] Figure 4 is the top view of the disabled chair that can make autonomous posture changes, which is the subject of the invention.

[0018] The figures are not required to be scaled and the details which are not necessary for understanding the present invention may be neglected.

[0019] Description of the Part References

[0020] 1. LIDAR sensor

[0021] 2. Chair

[0022] 3. Linear actuator

[0023] 4. Ultrasonic sensor

[0024] 5. Reclining mechanism

[0025] 6. Battery

[0026] 7. Task computer

[0027] 8. Power distribution board

[0028] 9. Drive motor

[0029] 10. Wheel

[0030] 11 . Stepper motor

[0031] 12. Rack and pinion gear

[0032] 13. Camera mi, mj: Position and ID information of objects

[0033] Uk: Control signal applied at time k

[0034] Xk: Predicted and updated position of the vehicle at time k

[0035] Zkj: Measurement taken of the object at time k

[0036] Detailed Description of the Invention

[0037] In this detailed description, the preferred embodiments of the invention are described only for clarifying the subject matter in a manner such that no limiting effect is created. The invention, whose profile view is shown in Figure 3, is about the structure of a disabled chair that can make autonomous posture changes. The user's treatment process must be transferred to the task computer (7) and subsequently the task computer (7) must initiate the process. After the software in the task computer (7) starts to run, the energy from the battery (6) is distributed to the relevant units (sensors (1 , 4), linear actuator (3), reclining mechanism (5), motors, task computer (7), etc.) through the power distribution board (8). After the movement starts, the LIDAR sensor (1 ) and the ultrasonic sensor (4) start calculating distance and location information according to the surrounding units. The task computer (7) processes the received data through the algorithm and starts adding new reference maps to the initially given reference 0 map. The LIDAR sensor (1 ) sends an infrared beam around it at a certain rate and allows data to be collected. Thanks to the software algorithm created, up-to-date maps are created at certain intervals. The ultrasonic sensor (4) will be positioned in certain visible areas of the chair (2) and will provide an alternative data flow to LIDAR data. It sends out sound waves at certain intervals and calculates the returning sound waves, giving location and distance data. The task computer (7) determines the location and maps simultaneously using the SLAM algorithm on the data obtained by the sensors (1 , 4). In addition, it controls the motors to move the chair (2) in the direction of the map, depending on the sensor (1 , 4) data, based on a predefined target or a determined treatment process. In addition, it controls the reclining mechanism (5) via a linear actuator (3). When the treatment ends or the power in the battery (6) drops to a certain value, it directs the chair (2) to the starting point. In a preferred embodiment, the task computer (7) directs the chair (2) to a charging station and connects it to charging. For this, optionally, at least one camera (13) is used, which creates image data so that the chair (2) can approach and connect to the charging station by centering it.

[0038] In the disabled chair embodiment that is the subject of the invention, there is a reclining mechanism (5) that changes the posture of the chair (2) on which the user sits while moving. After new reference maps start to be created, the reclining mechanism (5) is operated by the linear actuator (3) under the control of the task computer (7). After the posture change occurs, the movement of the disabled chair begins with the guidance of the task computer (7) and with the help of the motor assembly, accompanied by new reference maps. When the necessary data is received, the task computer (7) moves the stepper motor (11 ) located in the steering device. The movement of the driven stepper motor (11 ) is transferred to the front and rear axles through the rack and pinion gear (12) and direction is provided. The direct current motor (9) in the movement device converts the electric current it receives from the battery (6) into torque to the wheels (10) and the autonomous movement feature begins. When the patient's treatment process ends or the battery (6) level approaches a certain value, it returns to the starting point on the reference 0 map. The chair configuration, which is in charging position at the charging station, waits in sleep mode until the next data entry.

[0039] It has been deemed appropriate to use the Ackerman wheel model for the driving technique of the autonomous vehicle. Although modern vehicles do not use the Ackermann model exclusively, they have created their own models based on this model. This model is used quite frequently in SLAM (Simultaneous Locating and Mapping) algorithms research and can be found in articles. In the Ackerman model, the drive can be from the two front wheels or the rear two wheels. A driving technique that can provide instantaneous and soft reactions is needed in an autonomous stretcher or grocery cart, because it is likely to be involved in more unusual situations in the field. For this reason, using a driving technique that can react and maneuver to obstacles in a short time will ensure that the product works more efficiently. The Ackerman wheel model (driving model) offers a longer reaction time than the differential wheel model. Therefore, differential driving technique is used as the driving technique. Double maneuverability is provided with the help of servo motor (1 1 ). By repeating the similar movement of the front and rear axles, the effect of the turning angle is doubled.

[0040] Dynamic equations of the vehicle model are important in SLAM applications. If u(k) is the control signal applied to the vehicle at time k to shift the vehicle. In order to find the position of the vehicle at time k+1 , the dynamic model of the vehicle must be known. f(.): Kinematic model of the vehicle,

[0041] V(k): The speed of the vehicle at time k,

[0042] <$>(k): The angle of rotation applied to the wheel of the vehicle at time k,

[0043] 0(k): The amount of rotation of the vehicle relative to the xy coordinate plane,

[0044] L: The length of the vehicle between the wheels,

[0045] (x,y): The kinematic equations of the vehicle, including the position of the vehicle in the plane, will be as follows:

[0046] When the u(k) control sign above is applied to the vehicle, the position of the vehicle at time k+1 is found by the following equation.

[0047] In Figure 1 , the simultaneous positioning and mapping of an autonomous land vehicle is representatively shown. The hollow circles in the figure represent the objects that the vehicle puts on the map based on laser measurements, the filled circles represent the actual positions of the objects, the hollow vehicle symbol represents the position of the vehicle determined and updated from the distance counter and laser measurements, and the filled vehicle symbol represents the route requested from the vehicle, xk is the predicted and updated position of the vehicle at time k. mi and mj contain the position and ID information of the objects. Zk,j refers to the measurement taken at time k of the jthobject. The vehicle not only determines its location and follows the given route, but also measures the distance and location of objects and adds the objects to the map. This process is called SLAM, that is, simultaneous positioning or localization and mapping. The data received from the sensors and encoder are sent to the SLAM layer and added to the map simultaneously, and then data flow is provided to the motion controller of the vehicle with the new data received from the encoder.

[0048] With the data association method, the data received from the vehicle's sensors (1 , 4) are processed correctly and the accuracy of the current map is confirmed. The data association problem is the problem of the robot predicting that it has passed through the same place, that is, being able to recognize the same objects or the same obstacles. In other words, the robot decides whether the marker objects it encounters are observations of the marker objects that it has previously observed and added to the map or observations of a new marker object is called data association. If it cannot understand this when the closed loop ends, it creates its orbit incorrectly. Before adding the newly observed data to the map, it must associate it with the existing map. Algorithms such as Individual Adaptive Near Neighbor (IANN (BUYK)), Composite Adaptive Branching and Linking (CABL (BUDB)) and Joint Bounded Data Association (JBDA (BSVI)) are used in the group verification technique.

[0049] The chair (2) takes a central angle of 130°-150°wh ile in motion, allowing the patient to reach the stretcher position. The schematic change on this chair allows the autonomous vehicle to continue moving during medical intervention for the patient. In addition, from a medical perspective, this shape change makes a significant contribution to keeping the spine stable and distributing unexpected forces that may come on the spine in a balanced manner. In addition, this shape change of the chair is intended to optimize balance by bringing the center of gravity of the chair closer to the ground.

[0050] The reclining mechanism (5) will provide the schematic change of the chair via a linear actuator (3). Linear actuator (3) is a pneumatic piston that converts electric current into linear movement via a driver board. It is the system element that enables the reclining mechanism to work. The maximum weight that this mechanism (5) can carry is limited to 150 kg. This limit condition will have a significant impact on the selection of the linear actuator (3) required for the system. It determines the necessary conditions for choosing a thrust system with sufficient power to resist all resistances of the system. Our limit conditions are a 150 kg load and a central angle range of 137 degrees.

[0051] Figure 2 shows the posture of the reclining mechanism (5) of a reference chair (2) at an angle between 130°-150°. This value is the optimum range for the designed chair (2). Thanks to the optimization of the mechanism (5) limb dimensions, necessary changes can be made on these angles.

[0052] Selection of the linear actuator (3) required for the reclining mechanism (5) to operate is important. First of all, it determines the necessary conditions to choose a thrust system with sufficient power to resist all resistances of the system. In an example where the tilt is determined as 137°, the chair is 12°and the ver tical force is determined as F = 1500 N, the autonomous vehicle is assumed to be parallel to the ground. Using these values as reference, the ground equivalent of human weight is Fx (N): Fx= F*g*SiN (90-B)=1467.2 N

[0053] FActuator= / ^calculated as *COS(B)=1435.2 N

[0054] This force is the static force on the linear actuator (3) at its maximum length. The carried load cannot be treated as a static weight. The safety coefficient determined to take into account the system losses and dynamic loads is taken as S=2.

[0055] The actuator (3) power that should be selected in line with this value is as follows;

[0056] FActuator~FActuator *S-2870.4 N

[0057] Each actuator (3) selected above this calculated value is sufficient to operate the system. The linear actuator (3) of the reclining mechanism (5) selected as reference provides 3000 N power production. It is understood that the calculation made is correct in line with the reference chair (2).

[0058] When designing a disabled chair, it is necessary to create a universal design with an ergonomic understanding by using anthropometric data. There must be some restrictions when making this design. These are important parameters such as dimensioning, the load it will carry and suitability for the reclining mechanism (5).

[0059] The chair structure must be able to move a 150-kilogram mass, as the target creature, in a properly manner. Another important parameter is that the posture change keeps the center of gravity of the disabled chair at the center and does not create a security vulnerability while moving. Since it is intended to be used in a hospital environment in the short term, the chair should have a minimalist structure and dimensions that will not cause any problems. While determining these parameters, data from the article titled ‘A FIELD RESEARCH ON THE DETERMINATION OF ANTHROPOMETRIC DATA OF PEOPLE AGED 8-65: HIGHER EDUCATION INSTITUTION APPLICATION’ published in ergonomics journal in 2018. In this article, an experimental anthropometric data pool was created by measuring people's limb sizes in certain age ranges. Another issue that will affect the design is that the reclining mechanism (5) will have restrictive data on the design of the chair (2). Optimization studies should be carried out by comparing the reclining mechanism (5) and anthropometric data. The desired output of this report is to create a chair design that works properly in an optimized way with the data obtained and to present drawing examples. Limit conditions were determined by investigating the targeted load and estimated battery (6) options for the drive motor (9) selection. After mechanical calculations, motor power that can operate at optimum 80% efficiency was found. These findings are shown in Table 1 .

[0060] Table 1 : Important Parameters in Motor (9) Selection

[0061] These findings are the parameters required for the selection of the BLDC in-wheel motor (9), which is expected to operate at 80% efficiency. While calculating these parameters, the vehicle weight was calculated by taking a total mass of 200 kilograms as a reference, including the useful load and useless load. This angular velocity value was kept deliberately low. The reason is that since the load on it is alive, it does not cause health problems.

Claims

CLAIMS1. A disabled chair that can make autonomous posture change, characterized by comprising:• LIDAR sensor (1 ) and ultrasonic sensor (4), which calculate distance and location information according to surrounding units during movement,• reclining mechanism (5) that changes posture when the chair (2) on which the user is sitting is in motion,• linear actuator (3) that drives the reclining mechanism (5),• motors that direct and drive the wheels (10),• a task computer (7) that performs simultaneous position determination and mapping using the SLAM algorithm on the data obtained with sensors (1 , 4), controls the motors to move the chair (2) in the direction of the map based on the sensor (1 , 4) data based on a predefined target or a determined treatment process, controls the reclining mechanism (5) through the mentioned linear actuator (3), and directs the chair (2) to the starting point when the treatment ends or the power in the battery (6) drops to a certain value,• battery (6) that meets the energy needs of sensors (1 , 4), linear actuator (3), reclining mechanism (5), motors and the task computer (7).

2. The disabled chair configuration according to claim 1 , characterized by comprising the task computer (7) guiding the chair (2) to a charging station and connecting it to the charging station.

3. The disabled chair configuration according to claim 2, characterized by comprising at least one camera (13) which generates image data so that the chair (2) can approach and connect to the charging station centrally.

4. The disabled chair according to claim 1 , characterized by comprising a stepper motor (11 ) which provides guidance during movement under the control of the task computer (7).

5. The disabled chair according to claim 4, characterized by comprising rack and pinion gears (12) which transfer the movement of the stepper motor (1 1 ) to the front and rear axles.

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