ELECTRIC WHEELCHAIR, CONTROL METHOD THEREOF AND CONTROL SYSTEM THEREOF

An electric wheelchair, a control method thereof and a control system thereof are provided. The control method includes the following steps. Firstly, a control signal is outputted to the electric wheelchair by way of wireless according to a posture of a handheld controller. Then, the electric wheelchair performs a corresponding motion according to the control signal.

TECHNICAL FIELD

The technical field relates to an electric wheelchair, a control method thereof and a control system thereof, and more particularly to an electric wheelchair capable of performing a motion according to a posture of a handheld control device, a control method thereof and a control system thereof.

BACKGROUND

For conventional wheelchair, a rider himself needs to operate the wheel for making the wheelchair to go forward, back or make a turn. Alternatively, another person pushes the wheelchair on its back to make the wheelchair to go forward, back or make a turn. In order to care for disabled patients, some conventional wheelchair may be operated by a joystick. However, such way is still not very convenient for certain patients suffering from, for example, muscular dystrophy.

In addition, conventional electric wheelchair controls the speed and directions of the right wheel and the left wheel by one controller, and the left wheel and the right wheel can't be individually controlled.

SUMMARY OF THE DISCLOSURE

According to an embodiment of the disclosure, a control method for an electric wheelchair is provided. The control method includes the following steps. A plurality of control signals is outputted to a plurality of driving to devices of the electric wheelchair respectively by way of wireless technologies according to a posture of a handheld controller, wherein the number of the control signals is equal to the number of the driving devices; the electric wheelchair is controlled to perform a corresponding motion by the driving device of the electric wheelchair in accordance with the control signals; whether the handheld controller is at an abnormal state is detected; and if the handheld controller is at the abnormal state, temporarily stopping outputting the control signal to the electric wheelchair.

According to another embodiment of the disclosure, a control system for an electric wheelchair is provided. The control system includes a handheld controller and an electric wheelchair. The handheld controller includes an acceleration sensor and a controller. The acceleration sensor is configured to output a corresponding acceleration information according to a posture of the handheld controller. The controller is configured to output a plurality of control signals according to the acceleration information. The electric wheelchair includes a wheelchair body and a plurality of driving devices. The wheelchair body includes a plurality of wheels. Each of the driving devices is configured to detachably dispose on the wheels of the wheelchair body for controlling the wheels to rotate according to the control signals respectively to perform a corresponding motion, wherein the number of the control signals, the number of the driving devices and the number of the wheels are equal. The handheld controller is further configured to: detect whether the handheld controller is at an abnormal state according to the acceleration information; and if the handheld controller is at the abnormal state, respectively output a plurality of stop operation signals to the driving devices and then stop outputting the control signal to the electric wheelchair.

According to another embodiment of the disclosure, an electric wheelchair is provided. The electric wheelchair includes a wheelchair body and a plurality of driving devices. The wheelchair body includes a plurality of wheels. Each of the driving devices is detachably disposed on the wheels of the wheelchair body. The driving devices are configured to control the wheelchair body to perform a corresponding motion according to a plurality of control signals from a handheld controller, and the control signals are determined by a posture of the handheld controller; wherein the number of the control signals, the number of the driving devices and the number of the wheels are equal, and the driving devices are configured to, in response to a plurality of stop operation signals, stop driving the wheels.

The above and other aspects of the present disclosure will become better understood with regard to the following detailed description of the preferred but non-limiting embodiment (s). The following description is made with reference to the accompanying drawings.

DETAILED DESCRIPTION OF DISCLOSED EMBODIMENTS

FIG. 1illustrates a diagram of a control system100according to an embodiment of the present disclosure. The control system100includes an electric wheelchair110and a handheld controller120. The handheld controller120may control the electric wheelchair110to perform different motions according to a posture of the handheld controller120. For example, the handheld controller120has an X axis, a Y axis and a Z axis which are vertical to each other. The aforementioned posture is how the handheld controller120rotates around at least one of the X axis, the Y axis and the Z axis. In an embodiment, the operator (such as a patient) of the handheld controller120may sit on a wheelchair body111to operate the electric wheelchair110; however, such exemplification is not meant to be limiting. An operator also may operate the electric wheelchair110outside the electric wheelchair110.

The electric wheelchair110includes the wheelchair body111and a plurality of driving devices, such as a right driving device112and a left driving device113. The type of the wheelchair according to the present disclosure is not limited to the present embodiment, and it can be any kind of wheelchairs. The wheelchair body111includes a plurality of wheels, such as a right wheel1111and a left wheel1112. The right driving device112and the left driving device113are detachably disposed on the right wheel1111and the left wheel1112respectively for driving the right wheel1111and the left wheel1112to rotate. The right driving device112and the left driving device113may control the rotational speeds of the right wheel1111and the left wheel1112for controlling the motion speed and changing the direction of the wheelchair body111. In another embodiment, the number of the wheels of the wheelchair body111may be one or more than two, for example, three or even more. The number of the driving devices may be equal to the number of the wheels.

For example, the right driving device112and the left driving device113may control the rotational speed of the right wheel1111to be different from the rotational speed of the left wheel1112for controlling the wheelchair body111to make a turn. For example, when the rotational speed of the left wheel1112is controlled to be faster than the rotational speed of the right wheel1111, the wheelchair body111may turn right in place or turn right while advancing. Alternatively, when the rotational speed of the right wheel1111is controlled to be faster than the rotational speed of the left wheel1112, the wheelchair body111may turn left in place or turn left while advancing. However, such exemplification is not meant to be limiting. The wheelchair body111may perform other various motions through controlling the rotational speed of the right wheel1111and the rotational speed of the left wheel1112.

FIG. 2illustrates a diagram of functional blocks of the right driving device112of the handheld controller120ofFIG. 1. The right driving device112includes a first wireless control module1121, a first controller1122, a rotational speed sensor1123and a driving module1124. The first wireless control module1121is a wireless module using, for example, Bluetooth, radio frequency identification (RFID), WiFi, Near Field Communication (NFC), Long Term Evolution (LTE), etc. The rotational speed sensor1123may sense the rotational speed of the right wheel1111or calculate the rotational speed of the right wheel1111according to the rotational speed of a driving shaft of the driving module1124. The rotational speed sensed or calculated by the rotational speed sensor1123may be transmitted to the handheld controller120through the first wireless control module1121and may display on a display surface120uof the handheld controller120. The first controller1122is configured to control the driving module1124to drive the right wheel1111to rotate. The left driving device113has structures similar to that of the right driving device112, and the similarities are not repeated here. As long as the handheld controller120can receive the control signals S1and drive the right wheel1111and the left wheel1112of the wheelchair body111to rotate, the structures of the left driving device113and the right driving device112are not limited to the present embodiment.

As shown inFIG. 2, the handheld controller120includes a second wireless control module121, a second controller122and an acceleration sensor123. The control signal S1of the handheld controller120is transmitted to the first wireless control module1121of the right driving device112and the first wireless control module of the left driving device113through the second wireless control module121. The second wireless control module121is a wireless module using, for example, Bluetooth, RFID, WiFi, NFC, LTE, etc., such that the handheld controller120may communicate with the right driving device112and the left driving device113of the electric wheelchair110through the second wireless control module121by way of aforementioned wireless technologies.

FIG. 3illustrates a flowchart of a control method for the electric wheelchair according to an embodiment of the present disclosure.

In the step S110, a connection between the handheld controller120and the electric wheelchair110is established. For example, in using Bluetooth technology, the handheld controller120may be paired with the right driving device112and the left driving device113of the electric wheelchair110by way of Bluetooth protocols. When the handheld controller120is successfully paired with the right driving device112and the left driving device113simultaneously, the process proceeds to the step S120; otherwise, keep trying to establish the connection. In another embodiment, the handheld controller120may connect with the right driving device112and the left driving device113of the electric wheelchair110by way of other wireless technologies. Only when the handheld controller120is successfully paired with the right driving device112and the left driving device113simultaneously, the process proceeds to the step S120; otherwise, keep trying to establish the connection.

In addition, before the step S110, the handheld controller120may first finish the identity authentication. For example, the handheld controller120must be registered with a cloud server (not illustrated) in advance. Before the electric wheelchair110is operated, the handheld controller120may scan a barcode (such as two-dimensional bar code) on the electric wheelchair110. After the cloud server (not illustrated) receives the identity information of the handheld controller120, starting to verify the identity information of the handheld controller120. Since the handheld controller120has finished the identity authentication, the process proceeds to the step S110to establish the connection between the handheld controller120and the electric wheelchair110after the identity information of the handheld controller120is verified.

In the step S120, as illustrated inFIG. 1, the handheld controller120, according to the posture of the handheld controller120, outputs two corresponding control signals S1to the right driving device112and the left driving device113of the electric wheelchair110by way of wireless technologies for controlling the motion of the wheelchair body111. The control signal S1transmitted to the right driving device112by the handheld controller120and the control signal S1transmitted to the left driving device113by the handheld controller120may be the same type or different types. Compared with two driving devices being controlled by one control signal, the right driving device112and the left driving device113are controlled by two control signals S1respectively in the present embodiment, and thus the electric wheelchair110has excellent controllability and can perform various motions.

The aforementioned “posture” means the display surface120uof the handheld controller120is at a horizontal orientation, a vertical orientation or tilts toward, for example, forward, backward, rightward or rightward. In the present embodiment, the handheld controller120includes an acceleration sensor (G sensor)123. When the handheld controller120changes posture itself, the acceleration component sensed by each axis (such as the X axis, the Y axis and the Z axis) of the acceleration sensor123also changes accordingly, and thus the second controller122of the handheld controller120outputs different (or corresponding) control signal to the electric wheelchair110for controlling the wheelchair body111to perform different (or corresponding) motion.

In an embodiment, a relationship between the acceleration component sensed by each axis of the acceleration sensor123and the motion performed by the electric wheelchair110may be stored in a database (not illustrated), the second controller122may determine the motion of the wheelchair according to the database by inquiring or calculating for outputting the corresponding control signals S1. Such database may be stored in the electric wheelchair110, the handheld controller120or the cloud server. The aforementioned relationship between the acceleration component of each axis and the motion performed by the electric wheelchair110may be modified or set through an application program (APP), and the APP may be loaded by the second controller122of the handheld controller120. In addition, the control method for the electric wheelchair110may be completed through the APP.

In step S130, as illustrated inFIG. 1, the right driving device112and the left driving device113of the electric wheelchair110may control the electric wheelchair110to perform the corresponding motion according to two control signals S1, such as stationary (or stop), a forward motion (for example, toward +y axis), a backward motion (for example, toward −y axis), a rightward motion (for example, around −z axis) or a leftward motion (for example, around +z axis). The x axis, y axis and z axis ofFIG. 1of the electric wheelchair110are vertical to each other, and a plane defined by X axis and Y axis of the handheld controller120is substantially vertical to the display surface120uof the handheld controller120.

In addition, in the step S120and the step S130, if the electric wheelchair110disconnects with the handheld controller120, the processor proceeds to the step S110until the handheld controller120is successfully connected with the right driving device112and the left driving device113simultaneously. When the handheld controller120is successfully connected with the right driving device112and the left driving device113simultaneously, the processor proceeds to the steps S120and S130.

FIGS. 4A-4Cillustrate diagrams of several control methods of the present embodiment according to the present disclosure. As illustrated inFIG. 4A, when the handheld controller120is at the horizontal orientation, for example, X-Y plane of the handheld controller120being at the horizontal orientation P2, the wheelchair body111is controlled to be stationary. As illustrated inFIG. 4B, when the handheld controller120tilts forward, e.g., around −X axis, the wheelchair body111advances, e.g., toward +y axis. As illustrated inFIG. 4C, when the handheld controller120tilts backward, e.g., around +X axis, the wheelchair body111backs, e.g., toward −y axis. In addition, the speed of the wheelchair body111advancing or backing is proportional to an inclination angle of the handheld controller120. For example, the smaller the angle A1included between the display surface120uand the vertical orientation P1is (more inclined), the faster the advancing speed or the backing speed of the wheelchair body111is; however, such exemplification is not meant to be limiting.

FIGS. 5A-5Dillustrate diagrams of several control methods of the present embodiment according to the present disclosure. As illustrated inFIG. 5A, when the handheld controller120tilts rightward, e.g., around +Y axis, the wheelchair body111turns rightward, e.g., around −z axis. The smaller the angle A2included between the display surface120uand the vertical orientation P1is (more inclined), the faster the speed of the wheelchair body111turning rightward is. As illustrated inFIG. 5B, when the handheld controller120rotates to be at the vertical orientation P1, e.g., the display surface120ubeing at the vertical orientation P1, the speed of the wheelchair body111turning rightward is the fastest. As illustrated inFIG. 5C, when the handheld controller120ofFIG. 5Bcontinuous to rotate around +Y axis, the speed of the wheelchair body111starts to slow down. For example, the smaller the angle A2included between the display surface120uofFIG. 5Cand the vertical orientation P1is, the slower the speed of the wheelchair body111turning rightward is. When the display surface120uof the handheld controller120is at the horizontal orientation and faces downward, the wheelchair body111is controlled to be stationary or stop. As illustrated inFIG. 5D, when the handheld controller120tilts leftward, e.g., around −Y axis, the wheelchair body111turns leftward, e.g., around +z axis. Similarly, the smaller the angle A2included between the display surface120uand the vertical orientation P1is, the faster the speed of the wheelchair body111turning leftward is. The relationship between other left-tilting postures (for example, the display surface120uis at the vertical orientation P1, or/and the display surface120urotates to be at the downward orientation) of the handheld controller120ofFIG. 5Dand the motions of the electric wheelchair110may be similar to that of the right-tilting postures of the handheld controller120and the motions of the electric wheelchair110, and similarities are not repeated here.

As described above, the second controller122may determine whether the display surface120utilts from the horizontal orientation P2to the vertical orientation P1(as illustrated inFIGS. 5A to 5B). If the display surface120utilts from the horizontal orientation P2to the vertical orientation P1, the smaller the angle A2included between the display surface120uand the vertical orientation P1is, and the faster the motion speed of the wheelchair body111is. In addition, the second controller122may determine whether the display surface120utilts from the vertical orientation P1to the horizontal orientation P2(as illustrated inFIGS. 5B to 5C). If the display surface120utilts from the vertical orientation P1to the horizontal orientation P2, the larger the angle A1included between the display surface120uand the vertical orientation P1is, the slower the motion speed of the wheelchair body111is.

In an embodiment, the handheld controller120may tilt rightward and forward simultaneously for controlling the wheelchair body111turns rightward in advancing. In another embodiment, the handheld controller120may tilt leftward and forward simultaneously for controlling the wheelchair body111turns leftward in advancing.

In an embodiment, the handheld controller120may stop outputting the control signals S1to the electric wheelchair110in response to a stop instruction for stopping controlling the wheelchair body111. For example, the display surface120uof the handheld controller120displays a virtual key. When the virtual key is triggered (the stop instruction is outputted) by the operator, it represents that the operator attempt to stop the motion of the wheelchair body111. The handheld controller120responds to such stop instruction, outputting two stop operation signals to the right driving device112and the left driving device113of the electric wheelchair110respectively for making the electric wheelchair110to stop. The control signal S1may be achieved by various types, and the stop operation signal herein may be one of the various types which is the signal for stopping the electric wheelchair110. For example, when the right driving device112and the left driving device113receive the stop operation signals, stopping any motion performed by the electric wheelchair110, or forcing the moving wheelchair body111to stop (for example, brake). Then, the handheld controller120do not output any control signal S1to the electric wheelchair110unless the stop instruction is lifted, and accordingly, it can prevent the electric wheelchair110from performing unintended motion for ensuring the safety of the rider.

In another embodiment, the handheld controller120may restore the control signal S1to be outputted to the electric wheelchair110in response to a restoration instruction. For example, when the virtual key is triggered again (it represents that the restoration instruction is outputted), it represents the operator attempts to restart the control for the wheelchair body111. The handheld controller120responds to such restoration instruction, continuing outputting the control signals S1to the electric wheelchair110for restarting the control for the wheelchair body111. The aforementioned virtual key may be replaced by the physical key. In addition, during the control signals S1not being outputted to the electric wheelchair110, the connection between the handheld controller120and the electric wheelchair110may be maintained. In another embodiment, there is no connection between the handheld controller120and the electric wheelchair110, and the connection between the handheld controller120and the electric wheelchair110is established (for example, in the step S110) when receiving the restoration instruction.

In an embodiment, the second controller122may detect whether the handheld controller120is at an abnormal state. If the handheld controller120is at the abnormal state, the handheld controller120may stop outputting any control signal S1to the electric wheelchair110for preventing the handheld controller120from unintentionally controlling the electric wheelchair110. The description will be stated below accompanied withFIG. 6.

FIG. 6illustrates a flowchart of detecting whether the handheld controller120is at the abnormal state according to an embodiment of the present disclosure.

Firstly, the acceleration sensor123outputs current average value of acceleration a, wherein the average value of acceleration a is, for example, the square root of the square of the acceleration components of each axis of the acceleration sensor123, or root mean square value of the acceleration components of each axis of the acceleration sensor123. As illustrated inFIG. 7,FIG. 7illustrates a diagram of an array P1of the average value of accelerations a according to an embodiment of the present disclosure. The second controller122temporarily stores, in time sequence, the second designated number of the average values of accelerations a1to a50in the array P1, wherein the second designated number is, for example, 50, but may also be more or less.

Then, in the step S205, the second controller122forward pushes the average value of accelerations a2to a50other than the first one (count parameter C1=1) in the array P1. For example, the average value of acceleration aireplaces the average value of acceleration ai-1, wherein i is a positive integer ranging between 2 to 50, and the latest average value of acceleration a is temporarily stored in the last one of the array P1to become the average value of acceleration a50.

In the step S210, the second controller122sets the value of the count parameter C1as the value of the second designated number, for example, 50, and an initial value of the drop parameter C2is set to be zero.

In the step S215, the second controller122may determine whether the average value of acceleration ac1(in this step, that is a50) is equal to a predetermined value, for example, a value range of 5 to 9.8, or other value range, wherein the subscript C1of symbol a represents the value of the count parameter C1. If the average value of acceleration ac1is equal to the predetermined value, it represents the handheld controller120is at a normal operation, not at the abnormal state. Then, the processor proceeds to the step S220of operating as in the normal mode, the handheld controller120continues to output the control signals S1to the electric wheelchair110according to the posture of the handheld controller120. Then, the process proceeds back to the step S205, the handheld controller120continues to determine the next new average value of acceleration a. The aforementioned abnormal state means the handheld controller120is falling or at abnormal shaking rather than falling. If the average value of acceleration ac1is outside the predetermined value, it represents that the handheld controller120is in the abnormal state, and the process proceeds to the step S225. Then, the handheld controller120stops outputting any control signal S1to the electric wheelchair110for preventing the handheld controller120from unintentionally controlling the electric wheelchair110.

Then, in the step S230, the second controller122sets the value of the count parameter C1as 1 for determining the average value of acceleration a1from the first one of the array P1until all average value of accelerations a1to a50are determined and completed for determining whether the handheld controller120is falling.

In the step S235, the second controller122may determine whether the average value of accelerations ac1is less than a predetermined value (for example, 1). If the average value of accelerations ac1is less than the predetermined value, it represents that the handheld controller120is possibly falling, and the process proceeds to the step S240. If the average value of accelerations ac1is not less than the predetermined value, the process proceeds to the step S260.

In the step S240, since the average value of accelerations ac1is less than 1, the second controller122accumulates the value of the drop parameter C2. In the step S245, if the value of the drop parameter C2is accumulated to be the first designated number, for example, 5, the handheld controller120is determined to be at the falling state, and thus the process proceeds to the step S250. In the step S250, the second controller122transmits the stop operation signals to the electric wheelchair110, and the handheld controller120do not transmit any control signal S1to the electric wheelchair110unless the handheld controller120receives aforementioned restoration instruction for preventing the handheld controller120from the electric wheelchair110unintentionally controlling the electric wheelchair110and for ensuring the safety of the occupant. In the step S245, if the value of the drop parameter C2does not be accumulated to be the first designated number, the process proceeds to the step S255. In the step S255, the second controller122accumulates the value of the count parameter C1, and then continuing to determine the next average value of acceleration ac1of the array P1.

In the step S260, the second controller122may determine whether the value of the count parameter C1is the second designated number, that is, the second controller122determines whether the average value of acceleration ac1is the last one of the array P1. If the average value of acceleration ac1is the last one of the array P1, it represents all of the average values of accelerations ac1of the array P1have been determined, and the process proceeds back to the step S205to determine the next latest average value of acceleration a. If the average value of acceleration ac1is not the last one of the array P1, the process proceeds to the step S265to accumulate the value of the count parameter C1, and then the process proceeds the step S235to determine the next average value of acceleration ac1of the array P1.

As described above, the second controller122may temporarily store the second designated number of the average values of accelerations a in the array P1and then set the latest average value of acceleration as one member of the array P1. The second controller122may determine all average value of accelerations a of the array P1for determining whether the handheld controller120is falling when the latest average value of acceleration a is within the abnormal value range (it represents the handheld controller120is in the abnormal state, and handheld controller120is possibly falling or over-shaken). When the number of the average values of accelerations a of the array P1which is less than 1 is equal to or more than the first designated number, that the handheld controller120is determined to be falling.

As described above, in the operation method for the electric wheelchair in the present disclosure, the electric wheelchair is controlled to perform a corresponding motion through the change of the posture of the handheld controller. The term “posture” means the handheld controller or the display surface thereof is at the horizontal orientation, the vertical orientation and tilts toward one side, such as toward forward direction, backward direction, leftward direction and/or rightward direction, and “the corresponding motion” means advancing motion, backward motion, left-turning motion and/or right-turning motion. In addition, the handheld controller may control the corresponding motion speed of the electric wheelchair through the different postures of the handheld controller. The relationship between the posture of the handheld controller and the corresponding motion performed by the electric wheelchair are not limited to aforementioned embodiments, and any one of the aforementioned postures of the handheld controller may control the electric wheelchair to perform any one of the aforementioned motions. In addition, the relationship between the postures of the handheld controller and the motions performed by the electric wheelchair may be changed or set through the APP.