WO2003068342A1

WO2003068342A1 - Self-running skateboard

Info

Publication number: WO2003068342A1
Application number: PCT/JP2003/001049
Authority: WO
Inventors: Mitsunari Sukekawa
Original assignee: Mitsunari Sukekawa
Priority date: 2002-02-18
Filing date: 2003-02-03
Publication date: 2003-08-21
Also published as: JP2003237670A; JP3493521B2

Abstract

A self-running skateboard, comprising a moving means for performing various controls such as stoppage, forward movement, backward movement, speed setting, and change of direction by the movement of the weight and the control of the balance of an operator, wherein, to simplify a structure and allow running on a slope, running wheels (36) are connected to the front and rear of an integral board (31) through shock absorbing bodies (37) and steering mechanisms (30), the inclination of the operator riding on the board (31) is detected by strain sensors (32) fitted to the board (31), a motor (33) is controlled by a controller (35) to move the wheels (36) through a transmission device (38) to accelerate the board in the direction in which the weight of the operator is deviated according to the degree of the deviation, and the board (31) is tilted by the steering mechanisms (30) for changing the direction.

Description

Specification

Technical field of self-propelled skateboard

The present invention relates to a standing-type moving device using an electric motor or a prime mover, and performs self-stop, forward, backward, direction change, speed adjustment, etc. by moving the center of gravity of a driver on a board body. It relates to a runnable board. Background art

Conventionally, as a self-propelled skateboard in which the movement of the center of gravity of a driver is controlled by speed or the like, there is Japanese Patent No. 28877766. Figure 1 shows the structure of this skateboard. In the figure, the weight of the rear footrest 13 integrally connected to the skateboard main body 11 is measured by the sensor 15, and the weight is measured on the front footrest 12 connected to the skateboard main body. The weight is measured by the sensor 14, the ratio of the front weight to the rear weight is calculated by the control device 17, and the wheel 18 is rotated by moving the power 16 according to the result. In other words, by measuring the pressure applied to the front and rear wheels, and moving the skateboard in a direction where the weight of the driver is uneven, the driver can move without falling off the skateboard. . The method of turning is to change the direction of the wheels 19 by rotating the front footrests 12 parallel to the ground.

A skateboard steering mechanism using weight shift is described in US Pat. No. 2,510,722. Figure 2 shows a simplified view of this steering mechanism. The tire 21 is supported by a wheel axle 23 via a ball bearing. The strut 25 is integral with the wheel axle and is connected to the board body so that it can rotate about the axis K. The wheel axle 23 has a hole centered on the axis J. These holes are integrally fixed to the board body, and are connected so as to be rotatable about a support axis 24, which is a force axis J, coated with a hard rubber. In this structure, when the board body leans toward the wheel 21 with respect to the ground, the wheel 21 moves inward and the wheel 22 moves outward. Conversely, if you lean to the side of wheel 22, wheel 21 moves outward and wheel 22 moves inward. When the force for tilting the board is reduced, the resilient force of the hard rubber coated -The body is level with the ground. With this mechanism, the driver inclines the skate board body with respect to the ground and turns the skate board.

The conventional technique described above has the following problem. In Japanese Patent No. 27877766, both feet are placed on independent footrests to detect the position of the center of gravity of the driver, and the weight of each foot is detected. Therefore, it is necessary to divide the skateboard into at least two parts, and to provide a special mechanism to prevent the weight of one part from resting on the other. This complicates the structure and increases the manufacturing cost. Further, the steering mechanism is not operated by shifting the weight of the driver, and has a problem in operability. To compensate for this drawback, it is conceivable to use a steering mechanism according to U.S. Pat. No. 2,510,722. However, using the above-described technology, the front footrest and the rear footrest are integrally connected. Then, a part of one weight is detected by the other sensor, and the position of the center of gravity is erroneously detected depending on the position where the foot is put. Also, when the skateboard is tilted back and forth on a slope, the pressure distribution at the sole of the driver's foot changes, and if the skateboard deviates from the center of gravity detection position on a flat ground, a problem arises. In addition, since a weight sensor is provided between the steering mechanism and the footrest, a mechanism for absorbing the impact from the running wheels must be provided for each wheel. This complicates the structure and increases manufacturing costs.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has a method of measuring and calculating the position of the center of gravity of a driver using a simple mechanism, and a self-propelled skateboard for performing speed control and the like based on the result. The purpose is to provide. Disclosure of the invention

In order to achieve the above object, a self-propelled skateboard of the present invention includes a plurality of strain sensors mounted on an integrated board, a signal amplifier circuit for amplifying an output from the sensor, and a signal amplifying circuit. It is configured to include a circuit for performing calculations, a motor control circuit, a power supply, a motor, a transmission device, a tire, a steering mechanism, and a shock absorbing mechanism.

As a method of detecting the center of gravity using a plurality of strain sensors, a method of measuring and calculating the strain amount of at least four boards to determine the driver's weight and the four unknowns of the position of the center of gravity and the positions of both feet Is used. The operation mechanism uses a signal from the strain gauge to perform an arithmetic operation for detecting the position of the center of gravity of the driver using an arithmetic circuit, sends a signal corresponding to the operation result to the motor control circuit, and outputs the signal to the motor control circuit. By moving the skateboard, the skateboard is moved according to the ratio in the direction where the center of gravity is deviated. This allows the passenger to operate without falling off the skateboard. Steering is a mechanism that changes the direction of the wheels by tilting the skateboard with respect to the ground, making it easier to operate the skateboard. In other words, the forward, backward, stop, speed change, and direction change operations can all be controlled by the passenger's center of gravity, and the skateboard can be safely controlled even when the speed increases.

According to the present invention, the board on which the driver rides is integrated, and the steering mechanism and the strain sensor for measuring the center of gravity are respectively mounted at different locations on the board, so that the structure is simplified. It is also possible to attach a shock absorber between the board and the front and rear steering devices. This can reduce manufacturing costs and increase the rigidity of the device. For example, there is also an advantage that the self-propelled skateboard of the present invention can be constructed by attaching a sensor and power to a so-called skateboard without power. Further, in the self-propelled skateboard of the present invention, the position for placing the passenger's foot does not need to be particularly fixed within a certain range, so that the operability is improved. At the same time, the position of the center of gravity of the driver can be detected regardless of the inclination of the skate board, and even if the pressure distribution applied to the sole of the driver changes, the center of gravity of the driver can be accurately determined. Because it can be detected, it is possible to drive on a slope. BRIEF DESCRIPTION OF THE FIGURES

【Figure 1】

It is a side view which shows the conventional self-propelled skateboard.

【Figure 2】

It is a perspective view showing a steering mechanism.

[Figure 3]

FIG. 3 (a) is a side view showing a self-propelled skateboard according to one embodiment of the present invention, and FIG. 3 (b) is also a plan view. [Fig. 4]

It is a top view which shows one strain sensor.

[Figure 5]

It is a block diagram of an electric circuit.

[Fig. 6]

FIG. 3 is a block diagram illustrating an arithmetic circuit and a motor control circuit.

[Fig. 7]

It is the figure which showed typically the physical force which acts on a board when a driver | operator boarded. Coefficients and unknowns Shown in one-dimensional coordinates.

[Fig. 8]

It is a top view which shows the self-propelled skateboard which concerns on other embodiment (1) of this invention.

[Fig. 9]

It is a side view which shows the self-propelled skateboard which concerns on other embodiment (2) of this invention.

[Fig. 10]

FIG. 16 is a side view showing a self-propelled skate board according to another embodiment (3) of the present invention.

[Fig. 11]

It is a side view showing a self-propelled skateboard according to another embodiment (4) of the present invention.

[Fig. 1 2]

FIG. 36 is a side view showing a self-propelled skateboard according to another embodiment (5) of the present invention.

[Fig. 13]

FIG. 36 is a plan view showing a self-propelled skateboard according to another embodiment (6) of the present invention.

[Fig. 14]

FIG. 33 is a plan view showing a self-propelled skateboard according to another embodiment (7) of the present invention.

[Fig. 15]

FIG. 33 is a plan view showing a self-propelled skateboard according to another embodiment (8) of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the drawings.

(Description of configuration)

FIG. 3 is a diagram showing the configuration of the device of the present invention. FIG. 3-a is a diagram of the device viewed from the side, and FIG. 3-b is a diagram of the device viewed from below. The left and right sides of the drawing are the traveling directions of the device. In FIG. 3, the board 31 is a portion on which the occupant can put his / her foot, and is preferably a substance having sufficient strength and a large amount of strain when the occupant gets on the board. Force due to the balance between strength and elasticity For example, for wood plywood, a thickness of about 1 cm to 2 cm is preferred. The board 31 is preferably made of a material having a constant elastic coefficient between the wheel bases. For example, it may be a plywood of integrally formed wood. The strain sensors 32 (a), 32 (b), 32 (c) and 32 (d) are for detecting the strain of the board 31 and are bonded to the board 31. The number of strain sensors is four in this example, but the required number varies depending on the configuration of the device. In addition, more than the minimum required number may be installed to reduce measurement and other errors. These sensors are connected to the electric circuit box 35 by signal lines. Further, the electric circuit box 35 is connected to the battery 34 and the moda 33 by a lead wire. The power of the electric motor 33 is transmitted to the tire 36 via the transmission 38. The transmission device may be, for example, one in which gears are attached to a motor and a tire, respectively. The electric motor 33 and the wheel shaft 39 are integrally connected. The wheel shaft 39 has a steering mechanism 30 and is connected to the board 31 via a shock absorber 37. For example, a rubber-like elastic body may be used as the shock absorber. In addition, a shock absorbing mechanism can be attached to each wheel.

FIG. 2 shows an example of the steering mechanism. The passenger can tilt the skateboard board 11 with respect to the ground to change the direction of the skateboard.

Figure 4 is an example showing the configuration of one strain sensor. The strain gauges 41, 42, 43, and 44 are bonded to the plate 45. The board 45 is a plastic substance, a material having a smooth surface and a high thermal conductivity coefficient, such as a thin aluminum board, is preferred, but if the board 31 has a smooth surface, there is no board 45 May be. Two signal lines are connected to each strain gauge, and the resistance between the signal lines is, for example, 120 Ω. The strain resistance of the strain gauges increases when the adhered material is distorted. For example, if the plate 4 5 is distorted in the lengthwise direction of the gauge 4 1, the resistance change of the gauge 4 1 The rate is several times the rate of change in resistance of the gauge 42. However, when a temperature change occurs, the resistance of a strain gauge or a resistive element changes as much as the change due to strain, causing a measurement error. As a method of effectively reducing errors due to temperature or the like, a Wheatstone bridge circuit may be formed using four strain gauges, and a signal may be amplified using an operation amplifier circuit. However, when measuring only the difference between the two strain values, it is acceptable to attach two strain gauges vertically and configure a Wheatstone bridge circuit using a total of four strain gauges. In addition, a noise filter such as a coil is attached to the amplifier circuit to reduce measurement errors due to physical vibration of the device. Arithmetic averaging of measured values can also reduce measurement errors. The measurement error due to the fluctuation of the zero point can be easily reduced by storing the zero point and performing an operation using a digital circuit.

FIG. 5 is a block diagram showing the configuration of the electric circuit. The resistance change of the strain sensor 51 is converted into a voltage change by a signal amplification circuit 52 having a Wheatstone bridge circuit, a reference voltage generation circuit, and a voltage-operated amplification circuit, and input to the arithmetic circuit 53 as an analog signal. You. The arithmetic circuit 53 converts the signal from the signal amplifier circuit 52 into a digital signal using an A / D converter, and calculates the center of gravity of the occupant by arithmetically operating the value. An instruction to accelerate the motor is output to the motor control circuit 54 in the direction in which the position of the center of gravity is largely biased in accordance with the ratio, and the motor 56 is operated. By inputting information such as the number of rotations and the direction of rotation from the motor to the arithmetic circuit 53, the motor control can give instructions such as reducing the output of the motor when the speed exceeds a predetermined maximum speed, for example. It can be output to the circuit 54. In addition, since a current of several tens of amps flows through the motor control circuit, it is preferable to connect the battery 55 directly to the battery 55 through a lead wire. By connecting the charging circuit 57 to the battery 55, the battery can be charged without using an external charging device. The power charging circuit 57 may be an external device. A voltage conversion circuit can be incorporated in the charging circuit to enable charging from multiple power sources such as a commercial AC power source and a single battery power source for automobiles.

(Description of operation)

Next, the operation of the embodiment of the present invention will be described.

FIG. 6 is a block diagram showing the motor control circuit and the arithmetic circuit in detail. A clock signal is input from the clock generation circuit 67 to the arithmetic circuit 68 and the motor control circuit 65. The power supply 64 consists of an arithmetic circuit 68, a motor control circuit 65, a power MOSFET group 63, a rotor position detection circuit 62, Connect to force bra 66. If the operating voltages are different, input the appropriate voltage. The voltage signal obtained by amplifying the strain value detected by the strain sensor from lines Al, Bl, Cl, and D1 is input to the arithmetic circuit 68 with a built-in A / D converter. The arithmetic circuit 68 calculates the position of the center of gravity and the like, and outputs a PWM signal, a brake signal, a motor ON signal, and a motor operation direction signal to the motor control circuit 65 from lines E, F, G, and HI, respectively. When a star-connected three-phase brushless motor 61 is used as the power for the self-propelled skateboard, UH2, VH2 are used so that bidirectional current flows from two of the three coils from the motor control circuit. , One of WH2 and one of UL2, VL2, WL2. This signal is output to UH1, VH1, WH1, UL1, VL1, and WL1 through a photocoupler 66 that performs electrical insulation. The current flows to the element of the power MOSFET group 63 to which the ON signal is input, and the current flows to the two-phase coil among Ul, VI, and W1. An IGBT or the like may be used as a switch element. In the brushless motor, the rotor position needs to be detected, and the rotor one position detection circuit 62 and the motor control IC 65 detect the rotor one position. When a Hall element is used as a position detection sensor, U2, V2, and W2 are signals of Hall elements arranged at intervals of 120 degrees in electrical angle of the motor, and this signal is amplified by the rotor position detection circuit 62, and U3 Output to V3, W3. Also, a signal from the rotor one position detection circuit is output to the arithmetic circuit 68 to monitor the rotation speed and direction of the motor. A method of detecting the center of gravity by using a plurality of strain sensors will be described below. In Fig. 7, the passenger places one foot between points A and C, and places his foot between points B and D. A = a, B = 2L-a, C = Lb, D = L + b. Equation 1 below is an equation representing the amount of strain Ra at point A. Also, the distance from the origin 0 to both feet is X,

Let it be Y.

[Equation 1]

Ra E-K = a-Nl- (X-a) Ml g- (Y-) -M2-g + (2L-a) N2

The following equation 2 is an equation representing the amount of strain Rb at the point B, Rb. In Equations 1 and 2, g is the gravity acceleration, E is the longitudinal elastic modulus, and K is the section modulus.

[Equation 2]

Ra-E K = (2L-a) Nl- (2L-a-X) Ml g- (2L-a-Y) M2 g + a N2

Equation 3 below is an equation representing the section modulus K, where W is the board width and H is the board thickness.

[Equation 3] WH ¹

K =

6

Equation 4 below is an equation representing Ml.

[Equation 4]

Y-Z

Ml = M

Y—X

Equation 5 below is an equation representing M2.

[Equation 5]

Υ-Χ

Equation 6 below is an equation representing N1.

[Equation 6]

„2L-Z

= M g

2L

Equation 7 below is an equation representing N2.

[Equation 7]

N2 = — -M-g

2L

Equation 8 below is obtained from Equations 1, 2, 4, 5, 6, and 7.

[Equation 8]

_ „'Δα-Μ ■ g

Ra + Rb--

E K

Further, the following Equation 9 also Equation 1 below, Equation 2, Equation 4, Equation 5, Equation 6, _c [Equation 9] obtained from the formula 7

Ra-R _b = ^2a ^ ^L - ^{Z) M} ^

E K L

The amount of strain Rc at the point C can be expressed by the following equation (10).

[Equation 10]

Rc-E-K = (L-b) Nl- (L-b-X) Ml-g- (Y-L + b) M2g + (L + b) -N2 The amount of strain Rd at point D can be expressed by the following equation (11).

[Equation 11]

Rd-EK = (L + b) Nl-(L + bX) Ml-g-(YLb) M2 g + (Lb) N2 The following formula 12 is the above formula 1, formula 2, formula 4, formula 5, formula 6, It is obtained from Equation 7.

[Equation 12]

_C following equation 13 is obtained from the equations 9 and Equation 12 [Equation 13]

Equation 14 below is an equation representing the deviation of the passenger's center of gravity _c

[Equation 14]

M \-M2 X + Y-2Z

M Y-X

Equation 15 below is _c obtained from Equations 13 and 14.

[Equation 1 5]

【number

Finally, Equation 16 above is obtained from Equations 8 and 15 above. The expression 16 indicates that even if the fulcrums X and Y change, the position of the center of gravity can be detected accordingly. In other words, by performing the calculation of Equation 16 above, even if the pressure distribution applied to the sole of the operator's foot changes on a slope or the like, the center of gravity of the operator can be accurately detected. For example, the resistance change rate of the strain gauge is as follows.For example, when board 300 in Fig. 3 is made of aluminum with a width of 300 mm and a thickness of 10 mm. ¹⁰ (N / m ² ), and from Equations 3 and 8 above, if a is 50 mm, a strain of about 100 microstrain occurs in the strain gauge at the position of 32 (a) in FIG. Assuming that the gauge factor of the strain gauge is 2, the resistance increase rate is about 0.02%. In the self-propelled skateboard of the present invention, the arithmetic operation of the above equation (16) is performed by an arithmetic circuit, a signal is sent to a motor control circuit, and the motor is moved. It has a mechanism to move the board. This allows the passenger to operate without falling off the skateboard. In addition, the steering is a mechanism that changes the direction of the wheels by tilting the skateboard with respect to the ground, making it easier to operate the skateboard. In other words, the skateboard can be safely controlled even if the speed increases, by controlling the passenger's center of gravity in all of the operations of moving forward, backward, stopping, changing speed, and changing direction. In order for a person to board the instrument safely, first use the values detected by the strain sensors to calculate Equation 8 above. Calculation to detect whether a person is on the device. In addition, the above formula 16 is calculated, and when the difference between Ml and M2 is smaller than a certain value, the setting is made so that the operation of the present apparatus is enabled. This will also detect if the passenger has one foot between A and C and the other foot between B and D. In other words, when boarding the device, the passenger places his / her feet in the specified range and brings the center of gravity near the center of both feet to start operation of the device. In addition, it is possible to get on the device more safely by putting a brake on the device until the rider can operate it after putting one foot on the device. When the operation of the present apparatus is started, the above equation 16 is calculated, and the position of the center of gravity of the occupant is measured. This calculated value indicates a value up to one force, and the motor is output according to the value to accelerate the device. If the center of gravity is deviated in the direction opposite to the direction of travel, apply the brake. There are two methods of braking the motor, one is to excite the coil in the direction opposite to the direction of rotation of the rotor, and the other is to short-circuit each coil of the motor. Further, an electromagnetic disc brake or the like may be used. If an error occurs in the coefficients a and b in Equation 16, the values of the coefficients a and b are corrected from the center-of-gravity position measurement result. In addition, since the skateboard is distorted, Nl and N2 are not completely perpendicular to the ground, and a small error occurs in the center of gravity detection position. Therefore, the calculation formula may be corrected so as to obtain the optimum controllability when actually boarding. There is no need to add a new sensor to make this correction. Because the undetermined coefficients are only M, X, Y, and 、, and the number of sensors is four, so we only need to solve the four-way simultaneous equation. Since it is difficult to obtain an exact solution analytically, the actual calculation method is determined by numerical calculation, approximation formula, or empirical formula. In this sense, the above equation 16 can be said to be an approximate equation. However, the number of sensors may be increased to five or more to reduce measurement errors or to expand the range where the foot can be placed. Also, on a slope, it is preferable to determine whether the motor is uphill or downhill, and to provide more power to the motor if the vehicle is uphill, and to reduce the output of the motor when the vehicle is downhill. The slope angle of the slope can be calculated, for example, by calculating the ratio of the output to the motor and the rate of increase in the number of rotations of the motor. The measured center of gravity may be offset from front to back, and the direction may be changed by tilting the skateboard from the ground surface In the present invention, the weight of the occupant is constantly monitored, and It is preferable to stop the device when it gets off the device. Other Embodiments of the Invention

Hereinafter, other different embodiments (1) to (8) of the invention will be described with reference to the drawings.

(1) FIG. 8 is a view of the configuration of the device as viewed from below. The left and right sides of the drawing are the traveling directions of the device. The strain sensors 82 (a), 82 (b), 82 (c) and 82 (d) are bonded to the board 81. Tire 87 is fixed in direction with respect to board body 81, and has no steering mechanism. This configuration includes a control device 85, a motor 83, a battery 84, a tire 86, and a steering mechanism 80. In this configuration, the position of the center of gravity of the driver can be expressed by Expression 16 above. From this calculation, the motor 83 and the wheel 87 are moved in such a direction that the center of gravity of the driver is deviated so that the skateboard is accelerated according to the ratio.

(2) FIG. 9 is a view of the configuration of the apparatus viewed from the side. The left and right sides of the drawing are the traveling directions of the device. The integral board 91 may be shaped so as to form a cavity when viewed from the side as shown in the figure, and the control device 95 and the battery 94 can be attached to the cavity. Strain sensors 92 (a), 92 (b), 92 (c) and 92 (d) are bonded to the board 91. This configuration includes a motor 93, a tire 96, a steering mechanism 90, and an impact absorbing mechanism 97. In this configuration, the direction in which the center of gravity of the driver is deviated is detected by the strain sensor, and the motor 93 is moved and operated so that the skateboard is accelerated in accordance with the ratio.

(3) FIG. 10 is a view of the configuration of the apparatus as viewed from the side. The left and right sides of the drawing are the traveling directions of the device. The strain sensors 102 (a), 102 (b), 102 (c), 102 (d) are adhered to the board 101. The driver rides right and left so that the strain sensors 102 (c) and 102 () are on the soles of the feet 100. This configuration includes a steering mechanism 104, a battery 106, and a control device 107. In the configuration, the position of the center of gravity of the driving operator can be expressed by the above-mentioned formula 16. From this calculation, the motor 103 and the wheels are set so that the skateboard is accelerated in a direction in which the center of gravity of the driving operator is deviated according to the ratio. 105 moves.

(4) FIG. 11 is a view of the configuration of the device as viewed from below. The left and right sides of the drawing are the traveling directions of the device. Attach strain sensors 1 1 9 (&) and 1 1 9 (b) to board 1 1 1 and motor 1 1 3 (a) to drive left and right wheels 1 16 (&) and 1 16 (b) respectively. And 1 1 3 (b). It is okay to have no steering device between axle 1 18 and board 1 1 1. In this configuration, a notch 114, a control device 115, and a power transmission device 117 (a), 117 (b) are provided. By comparing the strain values of sensors 1 (19) (a) and 119 (b), The movement of the center of gravity of the occupant in the left and right directions is measured. Based on this result, the traveling direction is changed in a direction in which the center of gravity is deviated by making a difference between the rotation speeds of the left and right motors. By this steering mechanism, the direction can be changed with a small turning radius. Also, using the center of gravity of the driver detected by the strain sensors 112 (a), 112 (b), 112 (c), 112 (d) bonded to the board 111, the center of gravity of the driver is determined. Move and operate the motors 113 (a) and 113 (b) in the biased direction so that the skateboard is accelerated according to the ratio.

(5) FIG. 12 is a diagram of the configuration of the device as viewed from the side. The left and right sides of the drawing are the traveling directions of the device. Attach a footrest 129 to the front and back of the board 121, and attach its support 128 to the inside of the strain sensors 122 (&) and 122 (b). The direction in which the center of gravity of the driver is deviated is detected from the strain value detected by each sensor, and the motor 123 is operated by moving the motor 123 so that the skateboard is accelerated in accordance with the ratio. In this configuration, a battery 124, a tire 126, and a steering mechanism 127 are provided.

(6) FIG. 13 is a side view of the configuration of the device. The left and right sides of the drawing are the traveling directions of the device. The driver places his feet on the X and Y positions of the board 131. The strain sensors 132 (a), 132 (b), 132 (c) are bonded to the board 131. The direction in which the driver's center of gravity is deviated is detected from the strain value detected by each sensor, and the motor 133 is moved and operated so as to accelerate the skateboard according to the direction.

(7) FIG. 14 is a side view of the configuration of the apparatus. The left and right sides of the drawing are the traveling directions of the device. The wheel 146 is mounted on the center of the board, and the strain sensors 142 (a), 142 (b), 142 (c), 142 (d) are bonded to the board 141. The driver puts his foot between the strain sensors 142 (a) and 142 (c) and between the strain sensors -142 (b) and 142 (d).

In the direction where the center of gravity of the driver is biased, the motor 143 is operated by operating the motor 143 so that the skateboard is accelerated according to the proportion.

(8) Figure 15 is a view of the self-propelled skateboard seen from above. The left side of the drawing is the traveling direction of the device. A turn signal 153 is mounted on the rear part of the board 151 on which the wheel 155 is mounted, and when the driver steps on the switch 152 (a) or the switch 152 (b), the turn signal 153 is turned on. The brake lamp 154 lights up when the device slows down. Industrial applicability

It can be used as a convenient means of transportation and transportation, and as a so-called skateboard that plays sports. Further, it is possible to configure an apparatus for measuring a load distribution of a substance on an integrated plate by using a load detection method using a plurality of strain sensors.

Claims

The scope of the claims

1. An integrated board, running wheels connected to two or more places including the front and rear of the board, a drive unit that drives the wheels, and a drive unit that is moved by the center of gravity of the driver on the board A self-propelled skateboard comprising means for controlling forward / reverse drive, stop, forward, reverse, and speed adjustment of the skateboard.

2. A center-of-gravity position detection method characterized by detecting the inclination of a passenger on a board supported by a plurality of support points by measuring and calculating the board distortion at a plurality of points.

3. The self-propelled skateboard according to claim 1, further comprising a device for detecting the movement of the center of gravity of the driver by the method of detecting the position of the center of gravity, wherein the driver accelerates the driver in an inclined direction.

4. The self-propelled skate board according to claim 1, further comprising a shock absorbing mechanism between the board and the wheel.

5. The self-propelled skateboard according to any one of claims 1, 3, and 4, further comprising a steering device that changes direction with the inclination of the left and right boards with respect to the traveling direction.

6. A drive device that drives the left and right wheels independently of each other in the traveling direction, and a control means that changes the left and right driving speeds by moving the center of gravity of the left and right driving operators in the traveling direction to change the direction. The self-propelled skateboard according to any one of claims 1 to 3, further comprising:

7. The self-propelled skate according to any one of claims 1 or 3 to 6, comprising a turn signal connected to the board, means for operating the turn signal, and a brake lamp. board.