JP5827179B2 - Bicycle, center of gravity measurement system, and center of gravity measurement method - Google Patents

Description

  The present invention relates to a bicycle, a center of gravity measurement system, and a center of gravity measurement method for detecting the center of gravity during travel.

  In recent years, the use of bicycles as a means of transportation or for sports purposes has been increasing due to the increasing awareness of energy resource conservation and health-consciousness. Along with this, the types and uses of bicycles have also diversified. Due to the different frame shape and wheel size of the bicycle, the stable state during running for each type of bicycle also differs. In evaluating the stable state of a bicycle, for example, the mass of the bicycle, the wheel base, the wheel radius, and the position of the center of gravity have been used. Here, the position of the center of gravity of the bicycle varies as the steering wheel is turned off by the operator while the bicycle is traveling.

  Conventionally, a suspension method, a weighing method, or the like has been used as a method for measuring the center of gravity of a bicycle (for example, see Non-Patent Document 1). In the suspension method described in Non-Patent Document 1, one point A of the object to be measured is hung with a rope, and the weight is lowered from the point A to determine another point B on the vertical line. Next, a point C different from the points A and B is hung with a rope, and the weight is lowered from the point C to define another point D on the vertical line. Then, the point where the straight line AB and the straight line CD intersect is determined as the center of gravity. Further, in the weighing method described in Non-Patent Document 1, the center of gravity is calculated by measuring the load when the rear wheel is supported upright and the front wheel is moved up and down with a scale.

Takio Oya, “Kinematics for Bicycles”, Report from JST, p.1-8, 1978, No.2

  However, the suspension method and the weighing method described in Non-Patent Document 1 can measure the position of the center of gravity of a stationary bicycle, but cannot measure the change in the position of the center of gravity while the bicycle is running.

  Accordingly, an object of the present invention made in view of such circumstances is to provide a bicycle, a center-of-gravity measurement system, and a center-of-gravity measurement method capable of measuring the position of the center of gravity during traveling of the bicycle.

A bicycle according to the present invention that achieves the above object is provided with a center-of-gravity identifying feature for detecting a center of gravity position of a traveling bicycle, wherein the center-of-gravity identifying feature is at least in a stationary state of the bicycle. The center-of- gravity identification feature is located at a center of gravity, and the center-of-gravity identification feature is a marker attached to an attachment member protruding from the frame of the bicycle, and the marker is movable .

The predetermined measurement using a bicycle according to the present invention, it is possible to measure the position of the center of gravity of the running of the bicycle, further Ru can be visualized variation of the center of gravity position in the running of the bicycle.

  In the bicycle according to the present invention, it is preferable that the marker is moved by control based on a steering angle of a handle of the bicycle.

  According to this configuration, it is possible to visualize the position of the center of gravity of the bicycle, which has changed due to the operator turning the steering wheel during traveling.

  The center-of-gravity measurement system according to the present invention that achieves the above-described object is a center-of-gravity measurement system for detecting the center of gravity position of the entire running bicycle at least for a bicycle in which the position of the center of gravity of the entire bicycle in a stationary state is known. , Detecting the center of gravity position of the entire bicycle during traveling based on the steering wheel angle detector for detecting the steering angle of the steering wheel of the bicycle, the steering angle of the steering wheel, and the center of gravity of the entire bicycle in a stationary state. And a barycentric position detector.

  According to the center-of-gravity measurement system of the present invention, it is possible to measure the center-of-gravity position during traveling of the bicycle, which has changed due to the operator turning the steering wheel during traveling.

  Further, in the center-of-gravity measurement system according to the present invention, for the bicycle, the center positions of the front wheel system and the rear wheel system in a stationary state are known, and the center-of-gravity position detection unit further detects the detected steering angle of the steering wheel. Detecting the center of gravity of the front wheel system of the bicycle during traveling based on the position of the center of gravity of the front wheel system of the bicycle in a stationary state; It is preferable to detect the center of gravity position of the entire bicycle during traveling based on the center of gravity position of the rear wheel system of the bicycle and the center of gravity position of the entire bicycle in a stationary state.

  According to this configuration, it is possible to more accurately measure the center of gravity position of the bicycle, which has changed due to the driver turning the steering wheel during traveling.

  In the center-of-gravity measurement system according to the present invention, the center of gravity for moving the center-of-gravity identification feature attached to the bicycle at a center of gravity when the bicycle is stationary to the center of gravity of the detected bicycle. It is preferable to provide an identification feature moving unit.

  According to this configuration, it is possible to measure the position of the center of gravity of the bicycle, which has changed due to the driver turning the steering wheel while traveling, and to visualize the changed position of the center of gravity.

  The center-of-gravity measurement method according to the present invention that achieves the above-described object is a center-of-gravity measurement method for detecting the center of gravity position of the entire running bicycle at least for a bicycle in which the position of the center of gravity of the entire bicycle in a stationary state is known. Detecting a steering angle of the steering wheel of the bicycle; and detecting a center of gravity position of the entire bicycle during traveling based on the steering angle of the steering wheel and a gravity center position of the entire bicycle in a stationary state. It is characterized by including.

  According to the center-of-gravity measurement method of the present invention, it is possible to measure the center-of-gravity position while the bicycle is running.

  According to the present invention, it is possible to measure the position of the center of gravity while a bicycle is running.

1 is a side view of a bicycle according to an embodiment of the present invention. 1 is a side view of a bicycle equipped with a center-of-gravity measurement system according to an embodiment of the present invention. It is a functional block diagram for demonstrating schematic structure of the control mechanism which moves the gravity center identification characteristic in the bicycle shown in FIG. FIG. 6 is a schematic plan view illustrating a method for detecting the center of gravity of the entire bicycle based on the steering wheel steering angle, the front wheel system center of gravity, and the rear wheel system center of gravity. 3 is a flowchart for explaining a center-of-gravity measurement method according to an embodiment of the present invention.

  Hereinafter, embodiments of a bicycle, a center-of-gravity measurement system, and a center-of-gravity measurement method according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a side view of a bicycle according to an embodiment of the present invention. The bicycle 1 according to this embodiment includes a center-of-gravity identification feature 2 and an attachment member 3. The attachment member 3 is constituted by a jig, for example. The center-of-gravity identification feature 2 is provided to detect the position of the center of gravity of the bicycle 1 and is arranged to be located at or near the center of gravity of the bicycle 1 at least when the bicycle 1 is stationary. In this specification, from the viewpoint of simplification of measurement, the “static state” is described as a state where the steering angle is 0 ° and the front wheels and the rear wheels are on the same straight line in a plan view. However, it is of course possible to keep the front and rear wheels stationary so that they are not on the same straight line. The position of the center of gravity of the bicycle 1 is measured by the above-described suspension method or weighing method, for example. The center-of-gravity identification feature 2 includes a center-of-gravity marker attached to an attachment member 3 that protrudes in a shaft shape from the frame of the bicycle 1. The center-of-gravity marker is, for example, a white spherical marker, and is made of a material that is light enough to not substantially change the position of the center of gravity of the bicycle 1 due to its own weight. Similarly, the attachment member 3 is also made of a lightweight material.

  The bicycle 1 includes a handle 4 and a seat 10 as in a normal bicycle, and further includes a handle stem 5, a head tube 6, a fork stem 7, a fork 8, a down tube 9, a seat tube 11, a seat stay 12, And a frame constituted by the chain stay 13 and the like.

  Hereinafter, the terms “front wheel system” and “rear wheel system” are used for the bicycle 1 in this specification, and the front wheel system includes a handle 4, frame components such as a handle stem 5, a fork stem 7, and a fork 8. It is comprised including. The rear wheel system includes the seat 10 and frame components such as the down tube 9, the seat tube 11, the seat stay 12, and the chain stay 13. The components of the front wheel system and the rear wheel system are not limited to this.

  Using a bicycle having a marker arranged at the center of gravity in a stationary state like the bicycle 1, for example, by performing image measurement in a three-dimensional space using a motion capture system or the like, the running bicycle 1 It becomes possible to measure the center of gravity position. In addition, since the bicycle 1 is made by visualizing the position of the center of gravity by using only one marker constituting the center of gravity identification feature 2, it is more difficult than attaching a plurality of markers to the bicycle and measuring the position of the center of gravity using a motion capture system. The possibility that the marker may be hidden behind the object or the operator of the bicycle 1 is reduced. Therefore, the measurement accuracy of the center of gravity position can be improved. The center-of-gravity identification feature 2 of the bicycle 1 can be used in the measurement system and the measurement method described below to measure the center-of-gravity position of the traveling bicycle.

  FIG. 2 is a side view of a bicycle equipped with a center-of-gravity measurement system according to an embodiment of the present invention. The center-of-gravity measurement system according to an embodiment of the present invention detects the center of gravity position during traveling of the bicycle 20 whose center of gravity position in a stationary state is known. The center of gravity position of the front wheel system, the rear wheel system, and the entire bicycle 20 in a stationary state is known, for example, measured by a suspension method or a weighing method, and is stored in advance in the center of gravity position detector 15 or a memory (not shown). Is acquired as needed by appropriately accessing the storage unit by the gravity center position detection unit 15. The components of the front wheel system and rear wheel system of the bicycle 20 are the same as those of the bicycle 1 shown in FIG.

  The center-of-gravity measurement system includes a steering wheel steering angle detection unit 14 and a gravity center position detection unit 15. The steering wheel steering angle detector 14 detects the steering angle of the steering wheel 4 of the bicycle 20, and is constituted by a rotary encoder, for example. The center-of-gravity position detection unit 15 detects the center-of-gravity position of the entire running bicycle 20 based on the detected steering angle of the handle 4 and the known center-of-gravity position of the entire bicycle 20 in a stationary state. A processor having a function, for example, a CPU (Central Processing Unit), a DSP (Digital Signal Processor), or the like is used. The center-of-gravity position detection unit 15 determines the center-of-gravity position of the stationary bicycle 20 as a whole (the position at which the center-of-gravity identification feature 2 is attached to the seat tube 11 constituting the frame of the bicycle 20 by the attachment member 3). The position rotated by the rudder angle of the handle 4 is detected as the center of gravity position of the traveling bicycle. In this way, the center-of-gravity measurement system according to the present embodiment can measure the approximate center-of-gravity position of the bicycle, which has changed due to the operator turning the steering wheel while traveling. The detection of the center of gravity position of the traveling bicycle according to this embodiment is based solely on the rudder angle of the steering wheel 4, and therefore the approximate center of gravity position of the bicycle 20 projected on the traveling surface is detected. .

  The centroid measurement system can further include a centroid identification feature moving unit 16. The center-of-gravity identifying feature moving unit 16 sets the center-of-gravity identifying feature 2 attached to the position of the center of gravity of the bicycle 20 in a stationary state with respect to the bicycle 20 to the center of gravity position of the entire running bicycle detected by the center-of-gravity position detecting unit 15. Move. With this configuration, the center-of-gravity measurement system can visualize the center-of-gravity position of the bicycle 20 that has changed due to the operator turning the handle 4 during traveling. Thereby, it is possible to measure the position of the center of gravity of the traveling bicycle 20 only by attaching one marker to the bicycle 20 without attaching many markers to the bicycle 20. In other words, it is not necessary to calculate the position of the center of gravity based on the position information detected by detecting the positions of a large number of markers. It becomes possible to measure easily.

FIG. 3 is a functional block diagram for explaining a schematic configuration of a control mechanism for moving the center of gravity marker in the bicycle shown in FIG. The steering wheel steering angle detector 14 is constituted by, for example, a rotary encoder, and detects the steering angle θ of the steering wheel 4. Next, the calculation unit 21 of the center-of-gravity position detection unit 15 calculates the center-of-gravity position of the entire traveling bicycle 20 based on the steering angle θ as an angle centered on the center-of-gravity identification feature attachment position, and outputs it to the operational amplifier 22 as Φ ^command. To do. In the embodiment described above, Φ ^command = θ. The operational amplifier 22 amplifies the difference between the feedback value of the rotation angle Φ of the center-of-gravity identification feature 2 and Φ ^command at a predetermined ratio so as to be the drive voltage of the motor 23. The motor 23 is driven based on the voltage value input from the operational amplifier 22 and moves the centroid identifying feature 2 by the centroid identifying feature rotation angle Φ. This center-of-gravity identification feature rotation angle Φ is input to the operational amplifier 22 as a feedback value by the rotary encoder 24. The motor 23 and the rotary encoder 24 constitute the center-of-gravity identification feature moving unit 16. In this way, the center-of-gravity identification feature 2 can be moved in accordance with the change in the steering angle θ of the handle 4.

  Further, the center-of-gravity position detection unit 15 is based on the steering angle of the handle 4 detected by the steering-wheel steering angle detection unit 14 and the center-of-gravity position of the front wheel system of the bicycle 20 when the bicycle 20 is stationary. The center of gravity position of the front wheel system is detected, and based on the center of gravity position of the front wheel system during traveling, the center of gravity position of the rear wheel system in the stationary state, and the center of gravity position of the entire bicycle 20 in the stationary state, The center of gravity of the entire bicycle 20 can be detected.

A method of detecting the position of the center of gravity of the entire bicycle 20 in such a configuration will be described below with reference to FIG. FIG. 4 is a diagram for explaining a method of detecting the overall center of gravity of the bicycle based on the steering wheel steering angle, the front wheel system center of gravity, and the rear wheel system center of gravity. In FIG. 4, G _f represents the front wheel system center-of-gravity, the overall center of gravity, G _r is the position obtained by projecting the rear wheel system center-of-gravity on the running surface of the bicycle for each ground such as the G _T bicycle 20. In the figure, θ is the steering angle of the steering wheel, Φ is the rotation angle around the center of gravity identification feature mounting position of the entire center of gravity, H ₀ is the virtual handle line when the steering wheel is not cut, and H ₁ is the steering wheel cut by the steering angle θ. The virtual handle line in the state is shown. Overall center of gravity G _T bicycles, which corresponds to the center of gravity identification feature 2 in FIGS. Here, the handle line means an imaginary straight line passing through the center of rotation of the handle 4 projected on the traveling surface and indicating the rotation state of the handle 4.

As the steering wheel rotates, the steering wheel line changes from H ₀ to H ₁ , and the front wheel center of gravity G _f becomes the rotation front wheel center of gravity G _f1 which is the center of gravity when rotated by the steering angle θ. Therefore, it is possible to calculate the wheel system center-of-gravity G _r and the rotation wheel system center-of-gravity G _f1 and whole the straight line connected by a straight line gravity center G _T is the rotation angle which comes Φ the following are known in advance Instrumented (total It shows the center of gravity of the state where the center of gravity G _T is rotated by the rotation angle Φ as a rotation center of gravity of the entirety G _T1). More precisely, a rear wheel system center-of-gravity G relative distance to the overall center of gravity G _T from _r, the overall center of gravity G and the ratio of the distance to the front wheel system center-of-gravity G _f from _T, the rear wheel system center-of-gravity G entire rotation from _r centroid G _T1 Of course, it is possible to calculate the position of the rotation total center of gravity G _T1 by paying attention to the fact that the ratio of the distance from the rotation total center of gravity G _T1 to the rotation front wheel system center of gravity G _f1 is the same. In this case, the control mechanism for moving the center of gravity markers described above with reference to FIG. 3, the rotation angle [Phi as [Phi ^COMMAND, move the marker.

  FIG. 5 is a flowchart for explaining a center-of-gravity measurement method according to an embodiment of the present invention. Here, it is assumed that the total center of gravity, the front wheel system center of gravity, and the rear wheel system center of gravity in a stationary state of the bicycle are measured in advance and known, and the position information of each measured center of gravity is the center of gravity position of the center of gravity measurement system according to the present embodiment. It is stored in the detection unit 15 or stored in a storage device accessible from the barycentric position detection unit 15, and can be referred to by the barycentric position detection unit 15 as necessary.

  First, the steering angle detector 14 detects the steering angle of the steering wheel 4 of the traveling bicycle 20 (step S01). Next, the center-of-gravity position detection unit 15 applies the steering angle of the handle 4 detected in step S01 to the position information of the front-wheel system center of gravity of the bicycle 20 in a stationary state, so that the center-of-gravity position of the front wheel system of the traveling bicycle 20 Is detected (step S02). Further, the center-of-gravity position detection unit 15 uses the method described with reference to FIG. 4 to provide information on the center-of-gravity position of the front wheel system of the running bicycle 20 detected in step S02 and the rear position of the bicycle 20 in a stationary state. Based on the wheel system center of gravity and the position information of the entire center of gravity, the position of the center of gravity of the entire bicycle 20 during traveling is detected (step S03). By performing a series of these processes at a desired point in time while the bicycle 20 is traveling, the position of the center of gravity of the traveling bicycle 20 can be measured. Furthermore, by repeating these series of processes at regular intervals or continuously while the bicycle 20 is traveling, it is possible to measure a change with time in the position of the center of gravity of the traveling bicycle 20.

  The center-of-gravity position detection unit 15 directly applies the steering angle of the handle 4 detected in step S01 to the center-of-gravity position of the entire bicycle 20 (that is, the center-of-gravity identification feature 2 shown in FIGS. 1 and 2). It is of course possible to detect the approximate center of gravity position of the entire bicycle 20.

  It will be apparent to those skilled in the art that many changes and substitutions can be made within the spirit and scope of the invention. Therefore, the present invention should not be construed as being limited by the above-described embodiments, and various modifications and changes can be made without departing from the scope of the claims.

  For example, in the above embodiment, the center-of-gravity position detection unit 15 constituting the center-of-gravity measurement system is configured to be attached to the frame of the bicycle 20, but the center-of-gravity position detection unit 15 is implemented by a computer independent of the bicycle 20. Of course it is possible. In this case, the steering angle detection unit and the computer have a wireless unit, and are configured to transmit and receive the steering angle by wireless communication. By setting it as this structure, the measurement apparatus attached to the bicycle 20 can be minimized, and the possibility that the center-of-gravity measurement system will break down due to falling or the like can be reduced.

1,20 Bicycle 2 Center of gravity identification feature 3 Mounting member 4 Handle 11 Seat tube 14, 21 Steering wheel angle detection unit 15, 22 Center of gravity position detection unit 16 Center of gravity identification feature moving unit

Claims (6)

A bicycle having a center-of-gravity identification feature for detecting the position of the center of gravity of a running bicycle,
The center-of-gravity identification feature is located at the center of gravity position of the bicycle at least when the bicycle is stationary .
The center-of-gravity identification feature is a marker attached to an attachment member protruding from the bicycle frame, and the marker is movable . The bicycle according to claim 1 , wherein the marker is moved by a control based on a steering angle of a handle of the bicycle. At least a center of gravity measurement system for detecting the center of gravity of a bicycle that is running for a bicycle in which the center of gravity of the entire bicycle in a stationary state is known,
A steering angle detector for detecting a steering angle of the steering wheel of the bicycle;
Based on the steering angle of the steering wheel and the position of the center of gravity of the entire bicycle in a stationary state, a center of gravity position detection unit that detects the position of the center of gravity of the entire bicycle during travel;
A center of gravity measurement system. For the bicycle, the center of gravity position of the front wheel system and the rear wheel system in a stationary state is known,
The center-of-gravity position detection unit further detects the center-of-gravity position of the front wheel system of the bicycle that is running based on the detected steering angle of the steering wheel and the center of gravity position of the front wheel system of the bicycle in a stationary state, Based on the position of the center of gravity of the front wheel system of the bicycle during travel, the position of the center of gravity of the rear wheel system of the bicycle in a stationary state, and the position of the center of gravity of the entire bicycle in a stationary state, The center-of-gravity measurement system according to claim 3 , wherein the position is detected. Further, the center of gravity identification features attached to the center of gravity position in the stationary state of the bicycle to the bicycle, provided with a center of gravity identification feature moving unit that moves the center of gravity of the entire bicycle traveling detected, claim 3 or 4. The center-of-gravity measurement system according to 4 . At least for a bicycle in which the center of gravity position of the entire bicycle in a stationary state is known, a center of gravity measurement method for detecting the center of gravity position of the entire bicycle being run,
Detecting a steering angle of the steering wheel of the bicycle;
Detecting the position of the center of gravity of the entire bicycle during traveling based on the steering angle of the steering wheel and the position of the center of gravity of the entire bicycle in a stationary state;
A center of gravity measurement method.

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