KR102511163B1 - method for detecting and controlling the fall of the rear ground of an electric wheelchair - Google Patents

Abstract

The present invention is attached to the electric wheelchair with Velcro, the case 110 with a built-in control unit therein; A camera module cradle 130 provided at the top of the case; A camera module 130 rotatably seated on the camera module cradle and facing the rear of the electric wheelchair; A display panel 150 mounted on the electric wheelchair and showing a rear image taken by the camera module; Two laser line pointers 115 for irradiating a laser line (L) on the ground behind the electric wheelchair; As an electric wheelchair including an infrared sensor, rearward vision can be secured when the electric wheelchair is reversing, and the backward direction of the wheelchair can be predicted by irradiating a laser line on the back of the wheelchair, so that not only the wheelchair driver but also people around can inform the wheelchair's progress direction. By being present, it has the effect of providing safe driving and improving psychological satisfaction, and by including an infrared lamp that shines light backward on both sides of the camera together with a camera that takes a rear image of the electric wheelchair, at night or in the dark. In addition, the infrared lamp can be illuminated not only when reversing, but always illuminated during night driving, and to prevent overturning when the electric wheelchair is in reverse, the ground height is measured and the height of the ground is measured. In the event of a fall, an alarm is provided or an emergency braking function contributes to securing the user's safety.

Description

Method for detecting and controlling the fall of the rear ground of an electric wheelchair {method for detecting and controlling the fall of the rear ground of an electric wheelchair}

The present invention relates to a rear view securing system detachably provided in an electric wheelchair, and specifically, a rear view camera is provided to secure a rear view when the electric wheelchair is reversing, and auxiliary technologies for this are added, so that the electric wheelchair It is about a technique for suppressing the safe backward operation of

[0002] There is an electric wheelchair equipped with an electric motor as a device for assisting people with mobility, such as the handicapped and the elderly.

In addition, such an electric wheelchair is provided with equipment capable of controlling the driving direction in front and rear and left and right directions, and as an example of an electric wheelchair, there is Patent Publication No. 2002-0063053 and the like. Referring to the prior literature, an electric wheelchair and a driving control method thereof are disclosed in which a small DC motor or a brushless DC electric motor is individually coupled to each wheel to reduce the volume of the driving device and allow the wheelchair to be folded.

However, the conventional electric wheelchair has a function of adjusting the front, rear, left, and right directions, but there is a problem in that a rear view cannot be secured when reversing. In the case of a disabled person who has difficulty securing a rear view by turning the body, there is a risk of an accident such as colliding with an obstacle in a situation where reversing is required, and in particular, it is more problematic in a narrow space such as an elevator. In other words, after entering the electric wheelchair into the elevator, it is difficult to change direction due to space limitations, and therefore, when getting off the elevator, it is necessary to go backwards, but there is a lot of inconvenience because the rear view is not secured. They were exposed to risks such as physical damage from collisions and falls due to falling from the road surface.

The present invention is to solve the above problems, by providing a rear camera module and assistive technologies for a powered wheelchair for people with disabilities who have difficulty changing direction and reversing in a narrow space due to difficulty in looking backward, so that they are safe by watching the rear during the day and at night. Its purpose is to provide technology capable of driving.

The present invention is a rear vision securing system detachably provided to an electric wheelchair, which is attached to the electric wheelchair with Velcro and includes a case 110 having a control unit therein; A camera module cradle 130 provided at the top of the case; a camera module 130 rotatably seated on the camera module cradle and facing the rear of the electric wheelchair; A display panel 150 mounted on the electric wheelchair and showing a rear image taken by the camera module; Two laser line pointers 115 provided on the outer circumferential surface of the case and radiating a laser line (L) to the ground behind the electric wheelchair; and a distance sensor 117 provided on an outer circumferential surface of the case and configured to detect a distance from the electric wheelchair to a rear ground separated by a predetermined distance.

The camera module includes a camera 132 located at the center and capturing a rear image of the electric wheelchair; Infrared lamps 134 positioned on the left and right sides of the camera to illuminate the rear of the electric wheelchair, and the laser lines (L) irradiated from the two laser line pointers 115 are smaller than both rear wheels of the electric wheelchair. It is provided to be able to adjust the laser line irradiation angle of the two laser line pointers 115 so as to irradiate while forming a wider width by the interval.

The display panel 150 is attached to an arm support of an electric wheelchair, and the display panel is made of a touch panel, and the user can operate the camera by manipulating the touch panel to adjust the camera's shooting angle and shooting range.

A control unit for controlling the operation of a camera and a laser line point is provided inside the case, the case is detachably attached to the power wheelchair using Velcro, and the two laser line pointers 115 are attached to the power wheelchair. It is provided on the upper side of the rear wheel, so that the laser line is irradiated while forming a wide width by a predetermined distance from both rear wheels of the electric wheelchair.

The distance sensor repeatedly measures the distance from the electric wheelchair to the rear ground separated by a predetermined distance, and when the value of the measured distance is greater than a predetermined threshold value, it is determined that a fall has occurred and an alarm is provided, or It further includes a control unit to perform an emergency braking operation.

The present invention is also a method for detecting and controlling a drop of the ground at the rear of an electric wheelchair, wherein the distance sensor 116 is an axis perpendicular to the ground to measure the distance M to a specific ground spaced a predetermined distance to the rear of the electric wheelchair And installed to achieve a predetermined installation angle (θ), height (H), which is the distance from the distance sensor 116 to the ground in the vertical direction, the angle (θ) at which the distance sensor is installed, and the rear wheel of the wheelchair Step 1 to call the value of the radius (R) of; a second step of continuously collecting the distance (M) to the ground while the distance sensor forms the installation angle (θ); Step 3 of calculating the distance (L) from the wheelchair to a specific ground and the depth (D) from the specific ground using [Equation 1] below; and

[Equation 1]

4 steps of detecting and warning a step (chin, drop, etc.) when the D value is greater than 5 cm, and the warning of the 4 steps uses light or a warning sound. It provides step difference (chin, fall, etc.) detection and control method.

In addition, when the value of D obtained in [Equation 1] is greater than the predetermined depth value, a low-risk warning is issued when the value of the distance (L) obtained in [Equation 1] is less than 40 cm, and the [Equation 1] If the distance (L) value obtained from is less than 20 cm, a medium-risk warning is issued, and if the distance (L) value obtained from [Equation 1] is less than 10 cm, a high-risk warning is issued.

According to the present invention, the rear view can be secured when the electric wheelchair is reversing, and the backward direction of the wheelchair can be predicted by irradiating a laser beam on the back of the wheelchair, so that not only the wheelchair driver but also the pedestrian can be informed of the direction of the wheelchair, The effect of providing safe driving and improving psychological satisfaction is exerted.

In addition, by including an infrared lamp that shines light backward on both sides of the camera together with a camera that shoots a rear image of the electric wheelchair, it is possible to take a rear image even in a dark environment (night, etc.), and the infrared lamp illuminates only when reversing Instead, it is constantly illuminated during night driving, so that the user of the electric wheelchair in a dark environment can see the field of vision and recognize the obstacle.

1 and 2 are views of some configurations of the electric wheelchair rear vision securing system according to the present invention,
3 is a view of the electric wheelchair rear vision securing system shown in FIG. 1 mounted on the electric wheelchair,
4 is a view of a display panel mounted on an electric wheelchair among the components of the electric wheelchair rear vision securing system shown in FIG. 1;
5 is a view of the electric wheelchair moving backward using the electric wheelchair rear vision securing system according to the present invention,
6 is a state in which a distance sensor or the like operates in the electric wheelchair rear vision securing system according to the present invention,
7 is a flowchart of a function of recognizing a rear obstacle in the rear vision securing system for an electric wheelchair according to the present invention;
8 to 10 are views and flowcharts of calculating drop point information in the rear view securing system for an electric wheelchair according to the present invention.

Objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments taken in conjunction with the accompanying drawings. In addition, the terms used are terms defined in consideration of functions in the present invention, which may vary according to the intention or custom of the user operator. Therefore, definitions of these terms should be made based on the content throughout the present specification.

1 to 4 are some configurations of the electric wheelchair rear vision securing system according to the present invention and a state in which they are mounted on the electric wheelchair, and FIG. 6 is a state in which a distance sensor or the like operates in the electric wheelchair rear vision securing system according to the present invention. 7 is a flow chart of a function for recognizing rear obstacles in the rear vision securing system for an electric wheelchair according to the present invention, and FIGS. and a flowchart.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The present invention is composed of a detachable unit, so it is advantageous in that it is detachably provided to existing electric wheelchairs as well as new electric wheelchairs, and is a rear vision securing system that can be easily used by being mounted on electric wheelchairs.

Specifically with reference to the drawings, a case 110 attached to the headrest of an electric wheelchair with an attachment means 112 such as Velcro, a camera module 130 attached to the top of the case 110, and an electric motor It includes a display panel 150 attached to an arm support of a wheelchair. The case 110 can be attached with Velcro, and can be rotated when necessary by configuring the case to adjust a distance sensor and a laser irradiation angle to be described below.

The case 110 has a built-in controller or control device for controlling each component of the rear view securing system, and a camera module cradle 130 is located on the top of the case and rotates on the camera module cradle. Possibly the camera module 130 is seated. The camera module is mounted at an angle capable of properly securing a rear view by being capable of adjusting left and right, up and down, and rotating according to the user's convenience according to the width or height of the wheelchair to be used in the vertical direction.

The camera module 130 includes a camera 132 located in the center to capture a rear image of the electric wheelchair, and infrared lamps 134 located on both left and right sides of the camera to illuminate the rear of the electric wheelchair. The infrared lamp may be automatically turned on and turned on when reversing in a dark environment such as at night.

The rear image captured by the camera is used for obstacle recognition using machine learning-based image processing. The obstacle recognition function consists of obstacle tracking and approaching obstacle detection steps as follows. In detail with reference to FIG. 7 , in the obstacle tracking step, features of a rear image are extracted, and an optical-flow of the extracted features is calculated. Using the optical flow calculated here, an object showing a different motion (vector) from the ground information (vector) is classified as an obstacle from the background and detected. Detected obstacles are classified into wall/object/person through machine learning.

In the approaching obstacle detection step, the ratio of the classified obstacles in the rear image is calculated, and using this ratio, a warning light display or alarm is provided for each risk ratio, or it is linked to an emergency braking function. In addition, as well as showing the rear image to the user in real time, the image can be recorded and stored and used as evidence for legal disputes when the user suffers an accident or injury due to an obstacle.

In addition, the present invention is a configuration for displaying the backward direction and backward area of the electric wheelchair when the electric wheelchair moves backward, and includes two laser line pointers 115 for irradiating a laser line (L) on the rear ground, there is.

As shown in FIG. 2, the two laser line pointers 115 are attached to the lower portion of the case 110. That is, two holes are formed at an appropriate lower part of the case 110, and the laser light of the line pointer 115 attached to the inside of the case can be downwardly irradiated to the outside through the holes. The laser line indicates the backward range of the wheelchair moving backward, serves to inform an outsider of the wheelchair movement range, and at the same time presents the backward direction to the occupant of the powered wheelchair, enabling safe backward movement. FIG. 5 illustrates a situation in which an electric wheelchair descends while moving backward in a complex elevator as an example of use.

The laser line may be installed at a part adjacent to both rear wheels of the electric wheelchair to accurately indicate the backward direction of the electric wheelchair to mark the reverse area. That is, the line pointer 115 is installed directly above both rear wheels of the electric wheelchair, and the distance between the two line points is irradiated as wide as the predetermined distance from both rear wheels, so that the reverse area can be accurately displayed. The distance sensor measures the height of the ground to prevent overturning when the electric wheelchair moves backward.

In addition, the distance sensor 116 of the present invention measures the distance M to a specific ground at the rear of the wheelchair for the fall detection function. Referring to FIGS. 8 and 9, the distance measurement value repeatedly records the distance and depth from the location where the distance sensor 116 is attached to the ground at a specific point behind the wheelchair, and the displacement of the measured depth is a certain threshold If it is greater than the value, it is determined that there is a fall on the ground.

The fall detection function consists of three steps. In the first step, the distance (L) and depth (D) between the wheelchair and the falling point are calculated using the distance measurement value (M). In the second stage, a chin of 5 cm or more is inspected (depth value < -5 cm), and a red warning light is displayed, an audible alarm, and emergency braking is provided if a chin occurs. In step 3, the width and slope of the drop point are calculated through the downhill/uphill road test. If the width is greater than the diameter of the rear wheel (2R), the risk is low (15 degrees or less) It is divided into high risk (more than 15 degrees) and linked with warning light (high risk: red, low risk: yellow) display, alarm, and emergency braking (only high risk) function. The drop slope for judging low risk and high risk was derived and used through experimental research. The emergency braking function operates through a signal sent from the control unit to the wheelchair controller. To connect the wheelchair controller signal, the control unit transmits a signal via wireless (e.g., Bluetooth, infrared, etc.) to the wheelchair controller supporting the wireless emergency braking function, and to the emergency button switch to the wheelchair controller that does not support the wireless emergency braking function. It connects and transmits a signal through wire to perform emergency braking.

To explain the control method of the present invention again, the distance sensor 116 measures the distance M to a specific ground spaced a predetermined distance to the rear of the electric wheelchair at an axis perpendicular to the ground and a predetermined installation angle θ ), and the height (H), which is the distance from the distance sensor 116 to the ground in the vertical direction, the angle (θ) at which the distance sensor is installed, and the radius (R) of the rear wheel of the wheelchair Step 1 to call; a second step of continuously collecting the distance (M) to the ground while the distance sensor forms the installation angle (θ); Step 3 of calculating the distance (L) from the wheelchair to a specific ground and the depth (D) from the specific ground using [Equation 1] below; and

[Equation 1]

When the D value is greater than 5 cm (ie, when the depth of the step at a specific rear point has a depth of 5 cm or more), a fall is detected and warned in a 4 step; the warning in the 4 steps is performed using light or sound Available.

And, as shown in FIG. 10, when the value of D obtained in [Equation 1] is greater than a predetermined depth value, and when the value of the distance (L) obtained in [Equation 1] is less than 40 cm, a low-risk warning is issued. If the value of the distance (L) obtained from [Equation 1] is less than 20 cm, a medium-risk warning is issued, and if the value of the distance (L) obtained from [Equation 1] is less than 10 cm, a high-risk warning is issued to reduce the distance. can detect Here, the low risk may include a yellow warning light and alarm sound, the medium risk may include an orange warning light and alarm sound, and the high risk may include a red warning light, alarm sound, and emergency braking.

The present invention utilizes such a distance sensor to prevent safety accidents by warning the user in advance or applying a braking action to the wheelchair when there is a point where the ground suddenly lowers behind the backward wheelchair. Various devices may be used as the distance sensor, and as one example of them, a distance sensor using infrared rays may be used.

The display panel 150 is installed using a separate cradle on an arm support of an electric wheelchair, and the display panel is composed of a touch panel, so that a user operates the camera by manipulating the touch panel during a backward movement. In addition, by manipulating the touch panel, the user may be able to adjust the photographing angle and photographing range of the rear camera.

The present invention includes a camera for taking a rear image of the electric wheelchair and an infrared lamp that shines light backward on both sides of the camera, so that a rear image can be taken even at night or in a dark place, and the infrared lamp is only illuminated when reversing. In addition, by constantly illuminating the light while driving at night, the user of the electric wheelchair can easily identify the rear in a dark environment.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concept of the present invention defined in the following claims are also made according to the present invention. falls within the scope of the rights of

Claims (9)

As a method of detecting and controlling the fall of the rear ground using a rear view securing system of an electric wheelchair,
The rear view securing system of the electric wheelchair,
A cylindrical case 110 attached to the electric wheelchair with Velcro and having a control unit therein; A camera module cradle 130 provided at the top of the case; a camera module 130 rotatably seated on the camera module cradle and facing the rear of the electric wheelchair; A display panel 150 mounted on the electric wheelchair and showing a rear image taken by the camera module; Two laser line pointers 115 provided on the outer circumferential surface of the case and radiating a laser line (L) to the ground behind the electric wheelchair; And a distance sensor 116 provided on the outer circumferential surface of the case and detecting the distance to the rear ground spaced apart from the electric wheelchair by a predetermined distance;
The display panel is made of a touch panel, and the camera's shooting angle and shooting range can be adjusted by manipulating the touch panel.
The distance sensor 116 is installed to form a predetermined installation angle θ with an axis perpendicular to the ground to measure a distance M to a specific ground spaced a predetermined distance to the rear of the electric wheelchair,
Step 1 of calling the height (H), which is the distance from the distance sensor 116 to the ground in the vertical direction, the angle (θ) at which the distance sensor is installed, and the radius (R) of the rear wheel of the wheelchair;
a second step of continuously collecting the distance (M) to the ground while the distance sensor forms the installation angle (θ);
Step 3 of calculating the distance (L) from the wheelchair to a specific ground and the depth (D) from the specific ground using [Equation 1] below; and
[Equation 1]

4 steps of warning a fall when the D value is greater than 5 cm;
The warning in step 4 above is,
If the distance (L) value is less than 40 cm, a low-risk warning is issued,
If the distance (L) value is less than 20 cm, a medium risk warning is issued,
A method for detecting and controlling a fall of the rear ground of an electric wheelchair, characterized in that performing an emergency braking operation as a high-risk warning when the value of the distance (L) is less than 10 cm. delete delete delete delete delete delete delete delete

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