KR101677196B1 - In-wheel motor and Method for gain-tunning the same - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an in-wheel motor, and more particularly, to an in-wheel motor incorporating a wheel, a motor, a speed reducer, and a controller capable of low speed and / or constant speed control in an in-wheel motor constituting a driving unit of a mobile robot.
According to the present invention, a low speed constant speed control is possible by disposing a position detection PCB (Printed Circuit Board) incorporating a position detection sensor inside a fixed shaft (shaft).

Description

In-wheel motor and method for tuning the same

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an in-wheel motor, and more particularly, to an in-wheel motor incorporating a wheel, a motor, a speed reducer, and a controller capable of low speed and / or constant speed control in an in-wheel motor constituting a driving unit of a mobile robot.

The present invention also relates to a gain tuning method for controlling an in-wheel motor controlled by an external host controller by using such an in-wheel motor.

Generally, when configuring a mobile robot using a motor, parts such as a motor, a reducer, a motor driver, a belt for power transmission, and a poly are required. In this case, there is a problem that the various components are constituted, resulting in mechanical complexity and power transmission loss.

In order to solve these problems, it is possible to simplify the mechanical structure by constructing the driving unit by using the in-wheel motor, and to improve the power transmission efficiency, and it is applied to electric automobile, electric bicycle and the like.

However, when such an in-wheel motor is applied to an automobile, unlike a method in which the wheels are rotated by the power transmission through the engine-mission-drive shaft, a motor is built in the wheel rim, (Direct-drive) motor type that allows the vehicle to run.

Such an in-wheel motor can reduce the weight of the vehicle and reduce the energy loss during the power transmission process because the drive and power transmission devices such as the engine, the transmission, and the differential gear can be omitted, Motor.

In addition, the automobile equipped with the in-wheel motor has various advantages such as easy operation and assembly due to securing the internal space of the vehicle body, easy maintenance and replacement during traveling, and emergency operation.

1 is a conceptual diagram showing a driving force control system of a general in-wheel motor vehicle. 1, the in-wheel motor 100 has a brake disk and a rim wheel 210 of a wheel 200 coupled to the outside of the housing 110, and a tire 220 of the wheel 200 is connected to a rim wheel 210, respectively.

Such an in-wheel motor is mainly composed of a stator (not shown), a coil (not shown), and a rotor (not shown). Wherein the stator and the rotor are fixedly supported on a disk-shaped stator bracket and a rotor bracket spaced apart from each other by a predetermined distance in the vehicle width direction about a rotating shaft, the stator bracket is fixed to the vehicle body and is not rotatable, Is rotatably engaged at the same time by fastening each of the rotation centers of the rim wheel and the disk brake so as to coincide with the rotation axis.

However, the in-wheel motor mounted on such a vehicle has a problem in that it can not provide the low-speed constant-speed control function required by the mobile robot.

1. Korean Patent Publication No. 10-2012-0024170 2. Korean Patent No. 10-1127736 3. Korean Patent Publication No. 10-2010-0085647

The present invention has been proposed in order to solve the above-mentioned problems, and provides an in-wheel motor in which wheels, a motor, a speed reducer, and a controller capable of controlling a low speed constant speed within a range of 1 cm / s to 200 cm / The purpose is to provide.

It is another object of the present invention to provide an in-wheel motor and a gain tuning method of the in-wheel motor equipped with a smart function capable of constant speed, constant current, PWM (Pulse Width Modulation) mode support and various parameter setting and automatic gain tuning in a built- .

Another object of the present invention is to provide an in-wheel motor and a gain tuning method thereof, which are capable of configuring a bus type system through CAN (Controller Area Network) communication with an external host controller and further supporting RS232 to enhance hardware compatibility .

It is another object of the present invention to provide an in-wheel motor and a gain tuning method thereof that enable transmission of internal state information (speed, current, voltage, temperature) through a communication line.

It is a further object of the present invention to provide an in-wheel motor and a method of tuning the gain of the in-wheel motor, which make the space compact not mechanically complicated.

The present invention provides an in-wheel motor in which a wheel, a motor, a speed reducer, and a controller capable of controlling a low speed constant speed within a range of 1 cm / s to 200 cm / s are integrated.

The in-wheel motor includes an in-wheel motor having a wheel, a motor provided inside the wheel, a gear box assembled with the motor, and a shaft assembled to the upper end of the gear box,

A position detection sensor attached to a motor rotation shaft of the motor; And

And a holder for supporting the position detecting sensor.

The position detecting circuit board may further include a position detecting circuit board disposed inside the shaft for detecting a rotation amount of the motor according to the position of the position detecting sensor.

The position detection sensor may be an optical sensor or a magnetic sensor.

The controller may further include a controller circuit board disposed on the shaft and electrically connected to the position detecting circuit board.

In addition, the controller circuit board communicates with an external host controller using CAN communication.

The controller circuit board may be configured to perform one of a constant speed control mode, a constant current control mode, and a PWM (Pulse Width Modulation) control mode.

The controller circuit board may be configured to perform auto gain tuning to automatically detect an initial value of a gain according to a load condition.

In addition, the controller circuit board may further be configured to communicate with an external host controller using RS232 communication.

On the other hand, another embodiment of the present invention is a method of controlling an in-wheel motor, the method comprising: an upper-level controller confirming a load condition as an in-wheel motor is installed in a specific object; Transmitting the gain tuning start command to the in-wheel motor as the host controller confirms the load condition; Performing an auto gain tuning in which the in-wheel motor searches an initial gain value for a predetermined time; Transmitting a gain tuning completion signal to the host controller when the in-wheel motor completes gain tuning; And setting an initial gain value for which the in-wheel motor is searched for. The present invention provides a method for tuning an in-wheel motor gain.

In this case, the host controller controls the in-wheel motor in any one of a constant speed control mode, a constant current control mode, and a PWM (Pulse Width Modulation) control mode.

According to the present invention, a low speed constant speed control is possible by disposing a position detection PCB (Printed Circuit Board) incorporating a position detection sensor inside a fixed shaft (shaft).

In addition, another effect of the present invention is that it is possible to increase hardware compatibility and transmit internal state information because CAN (Controller Area Network) communication and RS232 communication can be performed with an external host controller.

Another advantage of the present invention is that a built-in controller can be implemented in an in-wheel motor to implement a constant speed, constant current, PWM mode support, various parameter settings, and a smart function capable of automatic gain tuning.

In addition, since the wheels, the motor, the speed reducer, and the controller are integrated with each other, the apparatus to which the in-wheel motor is applied is not complicated mechanically, but the space can be compact.

1 is a conceptual diagram showing a driving force control system of a general in-wheel motor vehicle.
2 is an exploded perspective view of an in-wheel motor 200 according to an embodiment of the present invention.
3 is a partially enlarged perspective view showing an enlarged portion of the position detecting magnet 250, the position detecting circuit board 253, the shaft 231 and the controller circuit board 260 in the configuration of the in-wheel motor 200 shown in FIG. to be.
4 is an external perspective view of the in-wheel motor 200 shown in FIG. 3 assembled.
5 is a cross-sectional view of the in-wheel motor 200 taken along the line X-X 'in FIG.
FIG. 6 is a diagram illustrating a concept of auto gain tuning according to an embodiment of the present invention. Referring to FIG.
FIG. 7 is a conceptual diagram showing a control mode according to the host controller 610 shown in FIG.
8 is a flowchart showing an auto gain tuning process of the in-wheel motor 200 according to an embodiment of the present invention.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

Like reference numerals are used for similar elements in describing each drawing.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component. The term "and / or" includes any combination of a plurality of related listed items or any of a plurality of related listed items.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the meaning in the context of the relevant art and are to be construed as ideal or overly formal in meaning unless explicitly defined in the present application Should not.

Hereinafter, an in-wheel motor according to an embodiment of the present invention and its control device will be described in detail with reference to the accompanying drawings.

2 is an exploded perspective view of an in-wheel motor 200 according to an embodiment of the present invention. Referring to FIG. 2, the in-wheel motor 200 includes a wheel 210, a motor 240 installed inside the wheel 210, a gear box 230 assembled with the motor 240, A shaft 231 assembled to the upper end of the gear box 230, and the like.

An outer wheel cover 211 covering the outer side of the wheel 210, an inner wheel cover 213 covering the inside of the wheel 210, a first bearing (not shown) provided outside the wheel 210, A second bearing 270 installed inside the wheel 210, a bearing cover 271 covering the second bearing 270, and the like.

The motor 240 is directly connected to the gear box 230 so that the gear box 230 is driven by the motor 240 to rotate the wheel 210. The motor 240 is provided with a motor rotation shaft 240-1 for outputting the rotational force of the motor 240 and an output rotation shaft 230-1 for outputting the rotational force of the gear box 230 is connected to the gear box 230. [ . In general, a DC (direct current) motor is mainly used as the motor 240, but the present invention is not limited thereto, and alternating induction type motors, AC synchronous type motors, and the like are also possible.

Of course, the gear box 230 is coupled to the motor rotation shaft 240-1 of the motor 240, the position detection magnet 250 is attached to the motor rotation shaft 240-1, The holder 251 is configured to be fixedly supported on the motor rotary shaft 240-1. The holder 251 is installed at the center of the upper surface of the gear box 230.

Although the position detecting magnet 250 is shown in FIG. 2, the present invention is not limited to the magnetic sensing method.

A position detection circuit board 253 is configured to detect the position of the position detection magnet 250. Since the position detecting circuit board 253 is disposed on the inner side of the lower end surface of the shaft 231, it is possible to configure the motor position detecting system without adding any additional space.

A position detection sensor (not shown) is mounted on the position detection circuit board 253 and detects the rotation amount of the motor 240 as the position detection magnet 250 rotates.

And a position detection circuit board.

The shaft 231 is fastened and assembled to the upper center portion 230-2 of the gear box 230. Further, the controller circuit board 260 is assembled to the shaft 231.

The controller circuit board 260 may be equipped with smart functions such as constant speed, constant current, PWM (Pulse Width Modulation) control mode support, various parameter setting and / or automatic gain tuning.

In addition, a communication circuit (not shown) is formed in the controller circuit board 260, and a system configuration of a bus type through CAN (Controller Area Network) communication with an external host controller is possible. In addition, it supports RS232 communication to enhance hardware compatibility. In other words, motor driver based on CAN communication usually supports constant speed and constant current but does not support PWM mode. Therefore, by using RS232, PWM mode is supported, so that constant speed or constant current control is possible in host controller.

Of course, through the communication line, the controller circuit board 260 transmits internal state information (including speed, current, voltage, temperature, etc.) to an upper controller (not shown) And so on. Further, it controls the driving of the motor 240.

In addition, the controller circuit board 260 has a reset function for factory value initialization. Reset for factory value initialization may be performed in software on the controller circuit board 260 and may be implemented by configuring a particular button or switch.

In addition, the controller circuit board 260 performs auto gain tuning to automatically detect an initial value of a gain according to a load condition.

Of course, a microprocessor, a memory, and the like are configured in the controller circuit board 260 to store a program, data, and the like for an algorithm for performing automatic gain tuning.

A gear 233 is formed on the side of the gear box 230. The gear 233 is assembled with the output rotation shaft 230-1 of the gear box 230 by extrapolating the shaft 231. [

3 is an enlarged view of the position detecting magnet 250, the holder 251, the position detecting circuit board 253, the shaft 231 and the controller circuit board 260 in the configuration of the in-wheel motor 200 shown in Fig. FIG. The motor rotation shaft 240-1 and the output rotation shaft 230-1 are spaced apart from each other and the shaft 231 is exposed to the upper surface of the gear box 230, And is coupled to the upper center portion 230-2 of the gear box 230 while surrounding the motor rotation shaft 240-1. The position detecting magnet 250 and the holder 251 and the position detecting circuit board 253 are covered by the shaft 231 and the controller circuit board 260 is positioned outside the shaft 231. [

4 is an external perspective view of the in-wheel motor 200 shown in FIG. 3 assembled. The shaft 231 is exposed on the center of the wheel 210 and the inner wheel cover 213 coupled with the bearing cover 271 is coupled to the wheel 210 via the fixing member 280 . Therefore, the inner wheel cover 213 covers the outside of the gear box 230 and the motor 240.

5 is a cross-sectional view of the in-wheel motor 200 taken along the line X-X 'in FIG. The motor rotation axis 240-1 of the motor 240 is positioned at the center of the wheel 210 while the output rotation axis 230-1 of the gear box 230 is positioned at the center of the motor rotation axis 240-1 Respectively. Therefore, the gear box 230 is coupled with the motor rotation shaft 240-1 of the motor 240 to rotate the output rotation shaft 230-1, and this rotation relationship is established between the gear box 230 and the motor Lt; RTI ID = 0.0 > 240 < / RTI > A shaft 231 is positioned on the motor rotation shaft 240-1 of the motor 240 and a gear 233 extruded on the shaft 231 is engaged with the output rotation shaft 230-1 of the gear box 230 All. As a result, the output rotation shaft 230-1 of the gear box 230 rotated by the driving of the motor 240 rotates the gear 233 extrapolated to the shaft 231, and the rotation of the gear 233 rotates inside The wheels 210 coupled to the inner wheel cover 213 are rotated via the fixing member 280 by being transmitted to the wheel cover 213. The motor rotation shaft 240-1, which is rotated by driving the motor 240, rotates the position detection magnet 250 fixed via the holder 251. As a result, the position detection circuit board 253 incorporated in the shaft 231 surrounding the motor rotation shaft 240-1 and the holder 251 and the position detection magnet 250 detects the rotation state of the position detection magnet 250 do.

FIG. 6 is a diagram illustrating a concept of auto gain tuning according to an embodiment of the present invention. Referring to FIG. 6 shows a state in which the in-wheel motor 200 is installed in the modified second wheel drive unit 602 in a state that the in-wheel motor 200 is installed in the first wheel drive unit 601 of the robot 600. FIG. Of course, the in-wheel motor 200 and the host controller 610 are connected to the communication line 620.

Although the robot 600 is illustrated in FIG. 6, the present invention is not limited thereto. The in-wheel motor 200 may be applied to an electric vehicle, an electric bicycle, a cleaner, an electric wheelchair,

As shown in FIG. 6, when the in-wheel motor 200 is installed in an installation subject to a different load condition, the gain for constant speed and / or constant current should be tuned appropriately according to the load condition.

In addition, an auto gain tuning function is provided to automatically detect the initial value of the appropriate gain according to the load of the system to which the in-wheel motor 200 is attached or the load condition depending on the application environment. This auto gain tuning function can be operated independently without a PC program.

FIG. 7 is a conceptual diagram showing a control mode according to the host controller 610 shown in FIG. Referring to FIG. 7, the host controller 610, as an external host controller, provides three control modes 710, 720, and 730. The three control modes are as follows.

① Constant speed control mode: Controllable from minimum 1cm / sec to maximum 200cm / sec

② Constant current control mode: Up to 10A Error Control within 0.1A

③ PWM control mode: When the external controller is used without using the internal control function, the controller circuit board (260 in Figure 2) can be used like a motor driver.

8 is a flowchart showing an auto gain tuning process of the in-wheel motor 200 according to an embodiment of the present invention. Referring to FIG. 8, as the in-wheel motor 200 is installed on a specific object, the host controller 610 confirms the load condition (step S810).

The host controller 610 transmits a gain tuning start command to the in-wheel motor 200 (step S820).

Upon receiving the gain tuning start command, the in-wheel motor 200 performs auto gain tuning for searching an initial gain value for a preset time (step S830).

Upon completion of the gain tuning, the in-wheel motor 200 transmits a gain tuning completion signal to the host controller 610, and the in-wheel motor 200 sets the found initial gain value (steps S840 and S850).

200: In-wheel motor 210: Wheel
211: outer wheel cover 213: inner wheel cover
220: first bearing 230: gear box
231: shaft 240: motor
250: Position detecting magnet 251: Holder
253: Position detecting circuit board 260: Controller circuit board
270: Second bearing
601: first wheel drive unit 602: second wheel drive unit
620: communication line

Claims (10)

A gear box having a wheel, a motor provided inside the wheel, an output rotary shaft rotated by a rotation shaft of the motor, and an output rotary shaft, and an in-wheel motor In this case,
The output rotation axis being spaced apart from the motor rotation axis located at the center of the wheel;
The shaft includes a position detection circuit board that surrounds the motor rotation axis so that the position detection sensor attached in the axial direction of the motor rotation shaft and the holder supporting the position detection sensor are located inside the lower end face, Detecting the rotation amount of the motor by the position detection of the position detection sensor;
When the gear box is driven by rotation of the motor rotation shaft by driving the motor, the rotational force of the wheels is transmitted from the inner wheel cover coupled via the fixing member, the rotational force of the inner wheel cover is transmitted from the gear, The rotational force of the gear is transmitted from the output rotary shaft, and the gear is extrapolated to the shaft, which is fastened and assembled with the upper center portion formed at the upper end of the gear box
Wherein the in-wheel motor is an in-wheel motor.
delete The method according to claim 1,
Wherein the position detection sensor is an optical sensor type or a magnetic type.
The method according to claim 1,
And a controller circuit board disposed on the shaft and electrically connected to the position detecting circuit board.
5. The method of claim 4,
Wherein the controller circuit board communicates with an external host controller using CAN communication.
5. The method of claim 4,
Wherein the controller circuit board executes one of a constant speed control mode, a constant current control mode, and a PWM (Pulse Width Modulation) control mode.
5. The method of claim 4,
Wherein the controller circuit board performs auto gain tuning to automatically detect an initial value of a gain according to a load condition. 5. The method of claim 4,
Wherein the controller circuit board further communicates with an external host controller using RS232 communication.
A gain tuning method of an in-wheel motor including components according to any one of claims 1 and 3 to 8,
Confirming a load condition by an upper controller as the in-wheel motor is installed on a specific object;
Transmitting the gain tuning start command to the in-wheel motor as the host controller confirms the load condition;
Performing an auto gain tuning in which the in-wheel motor searches an initial gain value for a predetermined time;
Transmitting a gain tuning completion signal to the host controller when the in-wheel motor completes gain tuning; And
Setting an initial gain value of the found in-wheel motor;
Wherein the gain of the in-wheel motor is set to a predetermined value.
10. The method of claim 9,
Wherein the host controller controls the in-wheel motor in any one of a constant speed control mode, a constant current control mode, and a PWM (Pulse Width Modulation) control mode.

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