Pedaled bicycle

Abstract

Provided is a pedaled bicycle which is suitable for a bicycle in which a cyclist must respond to disturbances while holding the handlebars and pedaling the left and right pedals, and which is capable of supporting the cyclist in responding to disturbances. In a pedaled bicycle 1, when a control device 53 performs control so as to cause a motor 521 to output support torque on the basis of a torque detection result from a torque detection unit 51, the torque detection unit 51, the motor 521, and the control device 53 are configured so as to respond in a period TP1 smaller than a half of 150 ms, which is a simple reaction time of a person who is a cyclist. With the torque detection unit 51, the motor 521, and the control device 53 operating at a speed exceeding what humans can simply react to, the motor 521 is controlled on the basis of the torque detected by the torque detection unit 51. The torque detection unit 51, the motor 521, and the control device 53 are configured as a human capability augmentation system SYS1 that augments human capability.

Description

Pedal bicycle

[0001] The present invention relates to pedal bicycles.

[0002] Pedal bicycles that use an electric motor to assist with riding or steering are well known. For example, Patent Document 1 discloses an electrically assisted bicycle in which an electric motor outputs an assisting force to help the cyclist drive the rear wheel. The electrically assisted bicycle described in Patent Document 1 has a target assisting force set so that a greater assisting force is obtained when pedaling while standing than when pedaling while sitting. The electrically assisted bicycle described in Patent Document 1 also detects whether the cyclist is standing and pedaling based on the pedaling force applied by the cyclist to the left and right pedals and the tilt of the vehicle body.

[0003] Furthermore, Patent Document 2 discloses an electric bicycle that performs power assist control, in which a power assist motor adds assist torque to the steering torque input to the handlebars by the cyclist. The electric bicycle described in Patent Document 2 performs forward power assist control when traveling at low speeds, and reverse power assist control when traveling at medium to high speeds. Furthermore, the electric bicycle described in Patent Document 2 performs reverse power assist control when traveling at medium to high speeds based on a set steering torque threshold and a torque change rate threshold.

[0004] Japanese Patent Publication No. 2018-001837 Chinese Patent Application Publication No. 103112540

[0005] A cyclist who rides a pedal bicycle by pedaling the left and right pedals tilts the bicycle left and right in the direction opposite to the pedal that is being depressed in order to move the bicycle straight. In other words, the cyclist holds the handlebars firmly and maintains the balance of the bicycle by tilting the bicycle left and right in accordance with the pressure on the left and right pedals.

[0006] Furthermore, bicycles are not only used on well-maintained paved roads in cities, but may also be used on rough surfaces such as cobblestone roads, gravel roads, forest roads, riverbanks, mountain trails, or roads with deteriorated asphalt surfaces. Therefore, when a bicycle is used on such rough surfaces, the front wheel may receive a load from the rough surface, causing external disturbances that cause the front wheel to rotate left or right. Furthermore, external disturbances may also occur even when the bicycle is used on well-maintained paved roads in cities.

[0007] When the cyclist grips the handlebars and steers the vehicle left and right in accordance with the pedals, the front wheel may be subjected to disturbances from the road surface. A function is needed to support the cyclist in responding to the disturbances while gripping the handlebars and steer the vehicle left and right in accordance with the pedals.

[0008] To provide a pedal bicycle that can support a cyclist in responding to disturbances even when the cyclist is gripping the handlebars and operating the bicycle body in the left and right directions in accordance with the depression of the left and right pedals.

[0009] A pedal-equipped bicycle according to one embodiment of the present invention has the following configuration: a steering column extending along the axial direction of a head tube included in a body frame and rotatably supported on the head tube; a front wheel supported by a fork connected to the lower part of the steering column in the vertical direction of the body frame; a steering unit connected to the upper part of the steering column in the vertical direction of the body frame and including a handlebar for steering the front wheel by rotating the steering column about the axis; a torque detector provided between the steering unit and the front wheel and detecting torque applied to the steering column in the rotational direction about the rotation axis; a motor outputting a support torque to the steering column about the rotation axis; and a control device controlling the output of the support torque by the motor based on the torque detected by the torque detector. With this configuration, when the cyclist is gripping the handlebar and maneuvering the bicycle left or right in accordance with the application of pressure to the left and right pedals, a situation may arise in which the front wheel is subjected to disturbance from the road surface. Here, if the speed range of the pedal bicycle is equally divided into an extremely low speed range, a low speed range, a medium speed range, a high speed range, and an extremely high speed range, the pedal bicycle is configured as follows.The torque detection unit, the motor, and the control device are configured as a human augmentation system that enhances the ability of a human to control the motor based on the torque detected by the torque detection unit at speeds beyond the ability of a human to simply react when a cyclist actively operates the handlebars while pedaling, at least at extremely low speeds, regardless of road surface conditions, straight-ahead driving, or turning. The torque detection unit, the motor, and the control device enhance responsiveness so that the period from when the torque signal reaches a proportion Pr, which is a certain value greater than the median of the span from the lowest to the highest measured value of the torque signal output from the torque detection unit and less than the highest value, to when the actual current value of the motor's operating current reaches the proportion Pr of its maximum value, is shorter than half of 150 ms, which is a simple reaction time (SRT) of the cyclist.

[0010] With the above configuration, the response times of the torque detection unit, the motor, and the control device are configured to be shorter than half the simple reaction time of 150 ms. Therefore, the control device controls the motor based on the detection results of the torque detection unit much faster than the cyclist's response to a load change due to an external disturbance. In other words, by increasing the responsiveness of the torque detection unit, the motor, and the control device so that the response times are shorter than half the simple reaction time of 150 ms, the system is configured as a human capability augmentation system that enhances a human's ability to control the motor based on the torque detected by the torque detection unit at a speed that a human simply cannot react to. In a scenario where the cyclist is gripping the handlebars and maneuvering the vehicle left or right in accordance with the pedaling motion on the left and right pedals, the torque detection unit, the motor, and the control device function as follows: Because the cyclist is firmly gripping the handlebars, the torque detection unit can quickly detect torque when a load is applied to the front wheel due to an external disturbance. The control device can then control the motor based on the results detected by the torque detection unit before the cyclist feels the load caused by the disturbance and operates the handlebars. More specifically, before the load applied to the front wheel due to the disturbance causes the vehicle body to tilt, or at the early stage of the vehicle body tilt, the torque detection unit, the motor, and the control device can cause the motor to generate a support torque in a direction that suppresses the vehicle body from tilting due to the disturbance, before the cyclist feels the load caused by the disturbance and operates the handlebars. As a result, a pedal-equipped bicycle having the above configuration can support the cyclist in responding to disturbances even when the cyclist is gripping the handlebars and operating the vehicle body left and right in accordance with their pressure on the left and right pedals.

[0011] [Clarification of Differences from Patent Documents 1 and 2] The specification requirements for the torque detection unit, the motor, and the control device are determined based on the usage scenario and purpose, and the torque detection unit, the motor, and the control device are designed to match those usage requirements. In other words, different usage scenarios and purposes result in different specification requirements or detailed designs for the torque detection unit, the motor, and the control device. Specifically, Patent Document 1 assumes standing-up pedaling, and its electric assist system is presumably configured with the responsiveness required for standing-up pedaling. Patent Document 2 discloses a power assist system that adds assist torque using a power assist motor to the steering torque input by the cyclist to the handlebars. Patent Document 2 describes a system that matches the steering torque input by the cyclist to the handlebars and the vehicle speed. In other words, since Patent Document 2 controls the system based on the steering torque input by the cyclist to the handlebars, it is presumed that the responsiveness is configured to match the simple human response time. One embodiment of the present invention is intended to address a scenario in which a cyclist receives a disturbance while gripping the handlebars and maneuvering the vehicle left and right by pressing the left and right pedals. In one embodiment of the present invention, the response times of the torque detection unit, the motor, and the control device are configured to be less than half the simple reaction time of 150 ms to accommodate this scenario. Another embodiment of the present invention is configured as a human capability augmentation system that enhances a human's ability to control the motor based on torque detected by the torque detection unit at a speed beyond a human's ability to simply react. It is clear that the specification requirements and detailed design of the torque detection unit, the motor, and the control device differ depending on the scenario and purpose. Patent Document 1 anticipates standing pedaling as a scenario, but does not disclose or suggest any disturbances. Furthermore, Patent Document 2 anticipates a cyclist's steering operation as a scenario, but does not disclose or suggest any disturbances.As such, neither Patent Document 1 nor Patent Document 2 discloses or suggests a usage scenario envisioned by one embodiment of the present invention, in which a cyclist receives a disturbance while gripping the handlebars and maneuvering the vehicle left and right in response to pedaling. The fact that a usage scenario is not envisioned means that the problem cannot be recognized. Because the usage scenario envisioned by one embodiment of the present invention is not disclosed or suggested, it is natural that the configuration of the torque detection unit, the motor, and the control device so that their response times are less than half the simple reaction time of 150 ms, or the configuration of the system as a human capability augmentation system, is not disclosed or suggested. Neither Patent Document 1 nor Patent Document 2 discloses or suggests the technical idea of ​​defining the relationship between a human's simple reaction time and the system's responsiveness in accordance with the characteristics of a pedal bicycle, as described below. Therefore, the effect of supporting the cyclist in responding to disturbances by controlling the motor based on the detection results of the torque detection unit using the control device sufficiently faster than the cyclist feeling a change in load due to a disturbance and responding by operating the handlebars themselves, even when the cyclist is gripping the handlebars and operating the vehicle left and right in accordance with the application of pressure to the left and right pedals, cannot be foreseen from Patent Documents 1 and 2. In other words, the problem or technical idea that one embodiment of the present invention is trying to solve is not disclosed or suggested in either Patent Document 1 or 2, and therefore it is impossible to foresee the effect that would be obtained by the configuration of one embodiment of the present invention.

[0012] [Selection or Detailed Design of Torque Detection Unit, Motor, and Control Device] In one embodiment of the present invention, the torque detection unit, the motor, and the control device are configured so that their response times are less than half the simple reaction time of 150 ms. By increasing the responsiveness of the torque detection unit, the motor, and the control device so that their response times are less than half the simple reaction time of 150 ms, the system is configured as a human capability augmentation system that enhances a human's ability to control the motor based on the torque detected by the torque detection unit at speeds beyond a human's ability to react simply. As a more specific example, the torque detection unit may be selected or detailed designed as a sensor system capable of detecting torque every few milliseconds. For example, the sensor system may be composed of a sensor body that outputs a linear signal and a signal processing circuit that digitizes the signal every few milliseconds. The processor, memory, etc. may be selected and detailed designed so that the control device processes signals received from the torque detection unit at frequencies ranging from several hundred Hz to several kilohertz and outputs command values ​​to the motor. The motor may be selected or detailed designed to minimize delay in response to current commands from the control device. The configurations of the torque detector, the motor, and the control device can be said to be clear if the usage scene and purpose are clear.

[0013] [Characteristics of Pedal Bicycles: Effects of External Disturbances on Pedal Bicycles] The following additional information is provided. Pedal bicycles have two or three wheels, or a total of three wheels, front and rear. The characteristics of pedal bicycles are explained in comparison with motorcycles. Pedal bicycles are lighter than motorcycles because they are used at lower speeds and the amount of power input to the vehicle is smaller. Pedal bicycles have narrower tires than motorcycles because they are used at lower speeds and the amount of power input to the vehicle is smaller. Because pedal bicycles are used at lower speeds than motorcycles, their steering geometry is designed to be highly responsive. More specifically, pedal bicycles are designed to have a sensitive front wheel due to their small caster angle or trail, and are therefore sensitive to external disturbances. Therefore, for example, when the front wheel is subjected to an external disturbance, the steering angle of the front wheel of a pedal bicycle is more likely to change left or right in a short period of time than a motorcycle. Furthermore, when the steering angle of the front wheel of a pedal bicycle changes left or right in a short period of time, the body of the pedal bicycle is more likely to lean left or right in a short period of time than a motorcycle. Furthermore, when the front wheel is subjected to an external disturbance, the steering angle of the front wheel of a pedaled bicycle is more likely to change left or right with a small load than a motorcycle. Furthermore, when the steering angle of the front wheel of a pedaled bicycle changes left or right with a small load, the body of the pedaled bicycle is more likely to tilt left or right with a small load than a motorcycle. Compared to motorcycles, pedaled bicycles not only have a shorter reaction time to external disturbances, but are also more susceptible to even small loads. Therefore, detailed system design tailored to the characteristics of pedaled bicycles is required. In particular, when the front wheel is subjected to an external disturbance, pedaled bicycles are fundamentally more dependent on human operation than motorcycles, so specification requirements and detailed design tailored to the characteristics of pedaled bicycles are required. When a pedaled bicycle is traveling straight, the front and rear wheels are facing in the same direction, and the center of gravity is located on the line connecting the contact points of the two wheels, so the body remains upright. However, for example, when the handlebars are turned left, the front wheel turns left and the contact point shifts to the left. As a result, the center of gravity shifts to the right, and the body naturally leans to the right.

[0014] From another perspective, a pedal bicycle according to one embodiment of the present invention may include the following configuration: the control device includes a supply pattern that defines the relationship between the torque signal and the motor's operating current. The supply pattern defines a change region between which the rate of change of the motor's operating current changes significantly when the torque signal is reduced from a certain value when the motor's operating current is being output toward zero, so that the support torque transmitted to the motor decreases or the frequency of support torque decreases when the cyclist actively operates the handlebars while pedaling straight ahead at an extremely low speed on at least a well-maintained paved road.

[0015] In a pedal-equipped bicycle according to one embodiment of the present invention, the torque detection unit, the motor, and the control device are configured as a human capability augmentation system that enhances a human's ability to control the motor based on the torque detected by the torque detection unit at speeds beyond a human's ability to simply react by increasing the responsiveness of the torque detection unit, the motor, and the control device so that the response time is less than half of the simple reaction time of 150 ms. When the cyclist actively operates the handlebars while pedaling straight ahead at an extremely low speed on a well-maintained road, excessive responsiveness can result in a large support torque transmitted to the cyclist or a high frequency of the support torque. To address issues that may arise when the torque detection unit, the motor, and the control device are configured as a human capability augmentation system, the supply pattern defines a change region within which the rate of change of the motor's operating current significantly changes when the torque signal is decreased from a certain value toward zero while the motor's operating current is being output, so that the motor's support torque transmitted to the cyclist decreases or the frequency of the support torque decreases. With this configuration, the motor operating current can be made smaller in a region where the torque signal value is closer to zero than in a region where the torque signal value is farther from zero than in the change region. Because the torque signal value is small, at least in situations where the cyclist actively operates the handlebars while pedaling straight ahead at extremely low speeds on a well-maintained paved road, the above configuration can reduce the support torque of the motor transmitted to the cyclist or reduce the frequency of the support torque. This reduces the discomfort felt by the cyclist due to small lateral movements of the vehicle body while riding in the above situation. Furthermore, the human capability augmentation system can be configured to have higher responsiveness. As a result, a pedaled bicycle with the above configuration can better support the cyclist's ability to respond to disturbances, even when the cyclist is gripping the handlebars and maneuvering the vehicle body left and right in accordance with their pressure on the left and right pedals.

[0016] According to another aspect, a pedal bicycle according to one embodiment of the present invention may include the following configuration: the control device includes a supply pattern that defines the relationship between the torque signal and the operating current of the motor. The supply pattern defines a change region within which the rate of change of the operating current of the motor changes significantly when the torque signal value increases from zero toward a certain value of the torque signal when the motor is outputting an operating current, so that the motor's support torque increases if the front wheel experiences a disturbance while the cyclist is pedaling and gripping the handlebars while moving straight.

[0017] In a human capability augmentation system configured to enhance a human's ability to control the motor based on the torque detected by the torque detection unit at speeds beyond a human's ability to react simply by increasing the responsiveness of the torque detection unit, the motor, and the control device so that the response time is less than half of the simple reaction time of 150 ms, the cyclist may wish to increase the support torque of the motor or increase the frequency of support torque when the front wheel is disturbed while gripping the handlebars while pedaling straight ahead. In a pedal-equipped bicycle according to one embodiment of the present invention, the supply pattern defines a change region within which the rate of change of the motor's operating current significantly changes when the torque signal value increases from zero toward a certain value when the motor's operating current is being output, so that the motor's support torque or the frequency of support torque increases. With this configuration, the motor operating current can be increased in a region where the torque signal value is farther from zero than the change region than in a region where the torque signal value is closer to zero than the change region. This allows the motor's support torque to be increased when the cyclist is gripping the handlebars and pedaling straight ahead and experiences an external disturbance to the front wheel. Therefore, the cyclist can be better supported when the cyclist is gripping the handlebars and pedaling straight ahead and experiences an external disturbance to the front wheel. As a result, a pedal-equipped bicycle with the above configuration can better support the cyclist's ability to respond to external disturbances, even when the cyclist is gripping the handlebars and steering the bicycle left and right by applying pressure to the left and right pedals.

[0018] From another perspective, a pedal bicycle according to an embodiment of the present invention may include the following configuration: the control device includes a plurality of supply patterns, and the plurality of supply patterns differ in the operating current of the motor at least in a region where the torque signal is larger than the change region.

[0019] According to the above-described configuration, the operating current is supplied to the motor according to one of a plurality of supply patterns, which differ in magnitude, average rate of change, supply timing, etc. of the operating current supplied to the motor based on the magnitude, average rate of change, occurrence frequency, occurrence time, occurrence timing, etc. of the torque signal generated according to the riding situation. The plurality of supply patterns differ in the operating current of the motor at least in the region where the torque signal is larger than the change region. This generates a support torque in a pattern suited to the riding situation, cyclist, speed, and road surface conditions, making it possible to support the cyclist in responding to the disturbance even while gripping the handlebars and maneuvering the vehicle body left and right in accordance with the cyclist's depressing the left and right pedals.

[0020] From another perspective, a pedaled bicycle according to one embodiment of the present invention may include the following configuration: the control device switches and controls the supply patterns of the plurality of types of operating currents manually by operation of the cyclist, automatically based on the road surface conditions on which the pedaled bicycle is traveling, or automatically based on physical quantities related to the pedaled bicycle.

[0021] In the above configuration, the cyclist can manually switch the supply pattern at their discretion. Alternatively, the supply pattern can be automatically switched depending on the output tendency of the support torque, depending on the situation, for example, whether the road is cobblestone or gravel. This allows the cyclist to respond to the disturbances by using the supply pattern most suited to the riding conditions, even while the cyclist is gripping the handlebars and maneuvering the vehicle left or right in response to the pedaling of the left or right pedal.

[0022] The terminology used in this specification is used for the purpose of defining particular embodiments only, and is not intended to limit the invention.

[0023] As used herein, "and / or" includes all combinations of one or more of the associated listed members.

[0024] As used herein, the use of "including," "comprising," or "having" and variations thereof identify the presence of stated features, steps, operations, elements, components, and / or equivalents thereof, but may include one or more of the steps, operations, elements, components, and / or groups thereof.

[0025] As used herein, the terms "attached," "connected," "coupled," and / or their equivalents are used broadly to encompass both "direct and indirect" attachments, connections, and couplings. Furthermore, "connected" and "coupled" are not limited to physical or mechanical connections or couplings, but can also include direct or indirect electrical connections or couplings.

[0026] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0027] Terms defined in commonly used dictionaries should be construed to have a meaning consistent with the relevant art and meaning in the context of this disclosure, and should not be construed in an idealized or overly formal sense unless expressly defined herein.

[0028] It will be understood that in describing the present invention, several techniques and processes are disclosed, each of which has distinct advantages and can be used in conjunction with one or more, or in some cases all, of the other disclosed techniques.

[0029] Thus, for the sake of clarity, the description of the present invention refrains from unnecessarily repeating every possible combination of the individual steps, but the specification and claims should be read with the understanding that all such combinations are within the scope of the present invention.

[0030] In this specification, an embodiment of a pedal bicycle according to the present invention will be described.

[0031] In the following description, numerous specific examples are set forth to provide a thorough understanding of the present invention. However, it will be apparent to one skilled in the art that the present invention may be practiced without these specific examples.

[0032] Accordingly, the following disclosure is to be considered as illustrative of the present invention and is not intended to limit the invention to the specific embodiments illustrated by the following drawings or description.

[0033] [Steering column] In this specification, the steering column is a part of a bicycle that is rotatably housed in the head tube and connected to the fork that rotatably supports the front wheel. The steering column is connected to a steering column connection part of the bicycle stem.

[0034] [Handlebar] In this specification, the handlebar refers to a bar handle that extends in the left-right direction. The handlebar connector of the bicycle stem is connected to the left-right center of the handlebar.

[0035] [Forward / Backward Direction] In this specification, the forward / backward direction means the forward / backward direction of the vehicle as seen by a rider riding the bicycle.

[0036] [Left and right direction] In this specification, the left and right direction means the left and right direction of the vehicle as seen by a rider riding the bicycle.

[0037] [Speed ​​Range] In this specification, a speed range refers to a range of speeds from a first speed to a second speed that is greater than the first speed. The speed range can be divided into multiple sections within the range. For example, the speed range can be divided into five sections: very low speed, low speed, medium speed, high speed, and very high speed. The very low speed may be the smallest speed range among the five divided speed ranges. For example, the speed range may include zero (km / s).

[0038] [Span] In this specification, span means the range between the highest and lowest values ​​detected by a measuring instrument.

[0039] [Cyclist] In this specification, a cyclist refers to a person who rides a pedal bicycle. A cyclist does not necessarily have to be a person with exceptional reaction ability such as an athlete, but refers to a person with reaction ability with an average or normal reaction time.

[0040] [A Simple Reaction Time (SRT) of a Human] In this specification, the term "simple reaction time of a human" refers to the reaction time required for a human to detect the presentation of a stimulus. Reaction time in human behavioral experiments is explained as follows, for example, in Ryosuke Niimi, Kazuhiko Yokozawa, et al., "Brain Science Dictionary," [online], last updated January 28, 2020, Brain Science Dictionary Editorial Committee, [searched September 30, 2024], Internet <URL: https: / / bsd.neuroinf.jp / wiki / %E5%8F%8D%E5%BF%9C%E6%99%82%E9%96%93>. Reaction time is the time from when a stimulus is presented to an organism to when an externally observable response to that stimulus occurs. Simple reaction time is the reaction time required when a known stimulus is presented and a predetermined response is made (simple detection task). Simple reaction time is the reaction time required to perform an action such as pressing a button as quickly as possible after hearing a sound. The "Encyclopedia of Brain Science" explains that simple reaction time is at most 150 ms.

[0041] [Proportion Pr (a proportion Pr) of a certain value (a certain value) that is greater than or equal to the median and less than or equal to the maximum value of the span from the minimum to the maximum value of the actual measured value of the torque signal output from the torque detection unit] In this specification, the proportion Pr of a certain value (a certain value) that is greater than or equal to the median and less than or equal to the maximum value of the span from the minimum to the maximum value of the actual measured value of the torque signal output from the torque detection unit means the following: First, the actual measured value of the torque signal output from the torque detection unit refers to the actual measured value of the signal output from the torque detection unit when a cyclist (a cyclist) of the pedaled bicycle actively operates the handlebars while pedaling, at least in the extremely low speed range, regardless of the road surface condition, straight-ahead driving state, or turning state. The certain value is greater than or equal to the median and less than or equal to the maximum value of the span from the minimum to the maximum value of the actual measured value of the torque signal, and is a value at which the actual measured value of the torque signal can be considered to have fluctuated sufficiently. The proportion Pr (a certain value) is the proportion of the span at which the actual measured value of the torque signal can be considered to have fluctuated sufficiently. For example, the proportion Pr can be 0.632≒1-1 / e (e is the base of the natural logarithm), a value widely used in calculating the time constant in physics or engineering (Wikipedia, Time constant, [online], last updated: September 18, 2024, 20:24 (UTC), [Retrieved October 5, 2024], Internet <URL: https: / / en.wikipedia.org / wiki / Time_constant#:~:text=Time%20constant.%20In%20physics%20and%20engineering,%20the%20time%20constant,%20usually>). Therefore, for example, if the measured torque signal value varies from zero to a maximum value and the ratio Pr is a value 0.632 ≒ 1 − 1 / e, which is also used in calculating the time constant, then a certain value will be the maximum value multiplied by 0.632.

[0042] [Human Ability Augmentation System] In this specification, a human augmentation system refers to a system that uses technology to add new capabilities beyond the natural limits of humans. A human augmentation system aims to enable humans to do things that are normally impossible and to achieve higher levels of performance or new functions by exceeding existing capabilities. On the other hand, a human ability assistance system uses technology to enhance the efficiency, accuracy, or level of existing human capabilities or to reduce the burden on humans. A human ability assistance system aims to enable humans to perform their natural capabilities more easily and smoothly. For example, the aforementioned Patent Document 2 describes an electrically assisted steering control system and an electrically assisted steering control method for an electric bicycle, which falls under the category of a human ability assistance system that aims to assist the cyclist in steering.

[0043] [Torque detection unit, motor, and control device configured as a human capability augmentation system] In this specification, the torque detection unit, motor, and control device configured as a human capability augmentation system refer to a system including at least a torque detection unit, a motor, and a control device. The human capability augmentation system also includes electrical connection members, including wired or wireless connection members, that electrically connect and / or communicably connect the torque detection unit, motor, and control device to each other.

[0044] [Supply Pattern] In this specification, the term "supply pattern" refers to a definition of the motor operating current corresponding to the torque signal. The supply pattern may be defined in a table format or as a function. The supply pattern may be defined as a rapid increase pattern in which the motor operating current increases significantly in response to an increase in the torque signal, a normal pattern in which the motor operating current increases moderately, or a mild pattern in which the motor operating current increases gradually. The motor operating current may increase linearly or change nonlinearly in response to an increase in the torque signal. A plurality of supply patterns may be defined depending on the driving situation.

[0045] [Change region] In this specification, this refers to a region where the rate of change of the motor's operating current changes significantly before and after. For example, the change region is a region where the rate of change of the motor's operating current changes significantly before and after when the torque signal is decreased from a certain value when the motor's operating current is being output toward zero. Also, the change region is a region where the rate of change of the motor's operating current changes significantly before and after when the torque signal is increased from zero toward a certain value when the motor's operating current is being output.

[0046] According to one embodiment of the present invention, a pedaled bicycle can be realized that can support a cyclist in responding to external disturbances even when the cyclist is gripping the handlebars and operating the body left and right in accordance with the pressure on the left and right pedals.

[0047] FIG. 1 is a left side view showing the schematic configuration of a pedal bicycle. FIG. 2 is a front view of a pedal bicycle according to a first embodiment of the present invention with the left and right pedals not depressed. FIG. 3 is a front view of a pedal bicycle according to a first embodiment of the present invention tilted to the left or right by pedal operation. FIG. 4 is a functional block diagram showing the functions of a control device. FIG. 5 is a flow chart explaining steering support when entering a rut. FIG. 6 is a diagram showing the schematic configuration of a stem mechanism and a steering support device of a pedal bicycle according to a first variation of the first embodiment of the present invention. FIG. 7 is a flow chart explaining steering support according to steering by a cyclist. FIG. 8 is a diagram explaining a steering range. FIG. 9 is a diagram showing an example of control based on two supply patterns. FIG. 10 is a diagram showing another example of a change area of ​​the supply pattern. FIG. 11 is a schematic diagram explaining steering support provided by a pedal bicycle.

[0048] Hereinafter, embodiments will be described with reference to the drawings. In each drawing, the same parts are designated by the same reference numerals, and the description of the same parts will not be repeated. Note that the dimensions of the components in each drawing do not faithfully represent the actual dimensions of the components and the dimensional ratios of the components.

[0049] Hereinafter, the arrow FR in the figures indicates the forward direction of the vehicle. The arrow RR in the figures indicates the rearward direction of the vehicle. The arrow UP in the figures indicates the upward direction of the vehicle. The arrow DN in the figures indicates the downward direction of the vehicle. The arrow LF in the figures indicates the leftward direction of the vehicle. The arrow RG in the figures indicates the rightward direction of the vehicle. Furthermore, in the following description, the up-down direction, left-right direction, and front-rear direction respectively refer to the up-down direction, left-right direction, and front-rear direction as seen by a cyclist riding the pedal bicycle.

[0050] (Embodiment 1) Fig. 1 is a left side view showing the schematic configuration of a pedaled bicycle 1 according to embodiment 1. Fig. 11 is a schematic diagram illustrating steering support provided by the pedaled bicycle 1. The pedaled bicycle 1 according to this embodiment is, for example, a two-wheeled vehicle. The pedaled bicycle 1 has a front wheel 21, a rear wheel 22, a body frame 10 including a head tube 11, a steering column 31, a fork section 32, a steering section 33, left and right pedals 41, and a steering support device 50. The configurations of the front wheel 21, the rear wheel 22, the body frame 10, and the left and right pedals 41 are similar to those of conventional bicycles, and therefore detailed description thereof will be omitted.

[0051] The steering column 31 is rotatably supported by the head tube 11 located at the front of the body frame 10. The steering column 31 extends along the axis of the head tube 11. The steering column 31 rotates around the rotation axis P, with the axis serving as the rotation axis P. The steering column 31 passes through the head tube 11 of the body frame 10. The steering column 31 extends obliquely so that the upper end is located rearward of the lower end.

[0052] The fork portion 32 rotatably supports the front wheel 21 at its lower end. The fork portion 32 is connected to the lower part of the steering column 31 in the vertical direction of the vehicle body. That is, the steering column 31 is connected to the upper end of the fork portion 32. The steering column 31 and the fork portion 32 form a so-called pine-needle fork. The fork portion 32 has a left fork portion 321, a right fork portion 322, and a connecting portion 323.

[0053] The left fork portion 321 supports the left portion of the axle of the front wheel 21. The right fork portion 322 supports the right portion of the axle of the front wheel 21. The connecting portion 323 connects the upper end of the left fork portion 321 to the upper end of the right fork portion 322, and is connected to the lower portion of the steering column 31. The left fork portion 321 and the right fork portion 322 may have a suspension mechanism.

[0054] The steering section 33 has a stem mechanism 331 and a handle 332. The stem mechanism 331 is attached to the upper end of the steering column 31. The handle 332 is supported on the steering column 31 by the stem mechanism 331.

[0055] That is, the steering unit 33 includes a handle 332 that is connected to the upper part of the steering column 31 in the vertical direction of the vehicle body and that steers the front wheels 21 by rotating the steering column 31 around the rotation axis P.

[0056] The steering support device 50 supports the steering of the steering wheel 332 based on the torque input to the steering wheel 332 or the steering column 31. The steering support device 50 has a torque detection unit 51, a motor 521, and a control device 53.

[0057] The torque detection unit 51 detects torque about the rotation axis P between the steering unit 33 and the front wheels 21. More specifically, the torque detection unit 51 is provided between the steering unit 33 and the steering column 31. The torque detection unit 51 includes a torque sensor that detects torque applied to the steering column 31 in the direction of rotation about the rotation axis P. The torque detection unit 51 generates a torque signal based on the detected torque and outputs the signal to the control device 53.

[0058] In the above-described configuration, the rotating parts that rotate around the rotation axis P when steered by the steering unit 33 are the various parts of the fork unit 32. In other words, these rotating parts are the parts below the steering column 31. Meanwhile, the torque detection unit 51 detects the torque between the steering unit 33 and the steering column 31. This makes it easier to lay out the torque detection unit 51 so as to avoid the rotating parts of the pedal-equipped bicycle 1. This improves the degree of freedom in arranging the torque detection unit 51.

[0059] The motor 521 outputs a support torque, which is a torque centered on the rotation axis P, to the steering column 31. In addition, torque centered on the rotation axis P is input to the motor 521 from the steering column 31.

[0060] The control device 53 controls the motor 521 based on the torque detection result by the torque detection unit 51. That is, the control device 53 controls the motor 521 based on the torque signal that is the output of the torque sensor, rather than the output of the roll angle sensor or the roll rate sensor. The operation of the control device 53 will be described in detail later.

[0061] The external force acting on the front wheel 21 is detected by the torque detection unit 51 as a torque centered on the rotation axis P of the steering column 31. Therefore, the torque detection unit 51 can linearly detect the torque generated by the external force on the front wheel 21. This can support the cyclist in responding to external disturbances even while maneuvering the vehicle left and right in accordance with the cyclist's depressing the left and right pedals 41.

[0062] (Regarding behavior of the bicycle body when pedaling) Using Figures 2 and 3, we will explain how a cyclist manipulates the pedaled bicycle 1 when they depress the left and right pedals 41, the left pedal 411 and the right pedal 412. Figure 2 is a front view of the pedaled bicycle 1 with the left pedal 411 and the right pedal 412 not depressed. Figure 3 is a front view of the pedaled bicycle 1 when tilted left or right by pedal operation. Note that in Figure 3, the pedaled bicycle 1 is shown in phantom lines in the neutral position N.

[0063] 2 and 3, when a cyclist of the pedaled bicycle 1 in the neutral position N depresses the left pedal 411 (see arrow A1), the cyclist pulls the left part of the handlebar 332 upward with the left hand (see arrow A2) to receive the upward reaction force generated by depressing the left pedal 411. A downward force is applied to the cyclist's body.

[0064] When the cyclist pulls the left part of the handlebar 332 upward in accordance with the magnitude of the pedaling force on the left pedal 411, the pedaled bicycle 1 is tilted to the right of the neutral position N (see arrow K1) around the contact point G of the front wheel 21 and rear wheel 22 with the road surface as the center of rotation. At this time, the cyclist shifts their body's center of gravity leftward relative to the pedaled bicycle 1 to maintain the direction of travel of the pedaled bicycle, whose center of gravity has shifted to the right. As a result, the center of gravity of the pedaled bicycle 1, including the cyclist, is maintained near the neutral position N when viewed from the front to rear.

[0065] When the cyclist moves the left pedal 411 to the lowest position, he or she finishes pulling up the left part of the handlebar 332. Next, the cyclist starts to depress the right pedal 412 and starts to pull up the right part of the handlebar 332 in the upward direction to receive the upward reaction force generated by depressing the right pedal 412.

[0066] The cyclist of the pedaled bicycle 1, which was tilted to the right of the neutral position N, pushes down on the right pedal 412 (see arrow A3) and pulls up the right part of the handlebar 332 with his right hand (see arrow A4) to absorb the upward reaction force generated by the pedaling. A downward force is applied to the cyclist's body. As a result, the pedaled bicycle 1 is moved from a position tilted to the right of the neutral position N toward the neutral position N, with the ground contact position G of the front wheel 21 and the rear wheel 22 as the center of rotation.

[0067] When the cyclist pulls the right part of the handlebar 332 upward in accordance with the magnitude of the pedaling force on the right pedal 412, the pedaled bicycle 1 is tilted to the left of the neutral position N around the contact point G of the front wheel 21 and rear wheel 22 with the road surface as the center of rotation. At this time, the cyclist shifts the center of gravity of their body to the right relative to the pedaled bicycle 1 in order to move the pedaled bicycle 1, whose center of gravity has shifted to the left, in a straight line. As a result, the center of gravity of the pedaled bicycle 1, including the cyclist, is maintained near the neutral position N when viewed from the front to rear direction.

[0068] To maintain the center of gravity of the pedaled bicycle 1, including the cyclist, near the neutral position N, the cyclist leans the pedaled bicycle 1 to the right in accordance with the pressure on the left pedal 411 and leans the pedaled bicycle 1 to the left in accordance with the pressure on the right pedal 412. When performing dancing, which is an operation of stepping on the left pedal 411 and the right pedal 412 while standing up from the saddle 7 in order to transmit greater driving force to the rear wheel 22, the cyclist increases the left-right tilt of the pedaled bicycle 1 compared to the left-right tilt when seated in the saddle 7. In this way, the pedaled bicycle 1 moves straight without turning by adjusting the direction and amount of lean in accordance with the pressure on the left pedal 411 and the right pedal 412.

[0069] While the cyclist is manipulating the vehicle body in the left-right direction in accordance with his / her depression of the left and right pedals 41, the cyclist performs an operation to tilt the vehicle body in the left-right direction, but does not perform an operation to rotate the steering unit 33. Therefore, the motor 521 does not output a support torque to the steering column while the cyclist is manipulating the vehicle body in the left-right direction.

[0070] (Details of Operation of Control Device) The operation of control device 53 will be described in detail with reference to Fig. 4. Fig. 4 is a functional block diagram showing the functions of control device 53. As shown in Fig. 4, control device 53 has a current command generation unit 531, a supply pattern REL1, and a voltage command generation unit 532. In addition, motor 521 is provided with an ammeter 55.

[0071] The torque signal SIG1 output by the torque detection unit 51 is first input to the current command generation unit 531. The current command generation unit 531 generates a current command Icom based on the supply pattern REL1.

[0072] The supply pattern REL1 defines the relationship between the torque signal SIG1 and the operating current I1 of the motor 521. The supply pattern REL1 may be stored in table format in a storage unit (not shown) of the control device 53, or may be realized as a function in the operational logic of the current command generation unit 531. For example, the supply pattern REL1 is defined so that a value of the operating current I1 of the motor 521 is output in response to input of each value of the range RNG1 of the torque signal SIG1. Note that, hereinafter, the torque signal SIG1 refers to the actual measured value of the torque signal SIG1, and the operating current I1 of the motor 521 refers to the actual current value of the operating current I1 of the motor 521.

[0073] Supply pattern REL1 is defined so that when the cyclist actively operates the handlebars 332 while pedaling straight ahead at an extremely low speed on at least a well-maintained paved road surface, the support torque of the motor 521 transmitted to the cyclist is reduced or the frequency of the support torque generation is reduced.

[0074] In the supply pattern REL1, the average rate of change of the operating current I1 of the motor 521 in the first section RNG11, in which the torque signal SIG1 ranges from zero to the change point Th1, is smaller than the average rate of change of the operating current I1 of the motor 521 in the second section RNG12, which has a larger value than the first section RNG11. More specifically, the average rate of change in the first section RNG11 is zero. That is, in the supply pattern REL1, a dead zone is provided in the first section RNG11. The average rate of change in the second section RNG12 is positive.

[0075] In this way, the supply pattern REL1 defines a change region REG1 in which the rate of change of the operating current I1 of the motor 521 changes significantly from zero to a positive value when the torque signal SIG1 is decreased toward zero from a certain value when the operating current Imot of the motor 521 is being output. The change region REG1 includes a change point Th1.

[0076] From another perspective, supply pattern REL1 is defined so that if the front wheel 21 is subjected to a disturbance while the cyclist is pedaling and moving straight and gripping the handlebars 332, the support torque of motor 521 increases. In other words, supply pattern REL1 defines a change region REG1 within which the rate of change of operating current I1 of motor 521 changes significantly when the value of torque signal SIG1 is increased from zero toward a certain value of torque signal SIG1 when operating current I1 of motor 521 is being output.

[0077] Therefore, the control device 53 can control the operating current I1 of the motor 521 so that the average rate of change in the first section RNG11 is equal to or less than half the average rate of change in the second section RNG12.

[0078] The predetermined value Th1 may be set, for example, based on approximately 5 Nm of torque generated when the cyclist actively operates the handlebars 332 while traveling straight on a well-maintained paved road.

[0079] Furthermore, the voltage command generating unit 532 converts the current command Icom generated by the current command generating unit 531 into a voltage command Vcom and outputs it to the motor 521. The motor 521 operates by a current flowing based on the voltage command Vcom. As a result, the motor 521 outputs a support torque to the steering column 31. Furthermore, the voltage command generating unit 532 obtains the value Imot of the current flowing through the motor 521 from an ammeter 55 provided in the motor 521, and performs feedback control so that the value Imot of the current flowing through the motor 521 becomes a target value.

[0080] Th21 shown in the graph of torque signal SIG1 represents a value of 63.2% of the span between the minimum value Sbot and the maximum value Stop of the actual measured value of torque signal SIG1. Furthermore, Th22 shown in the graph of operating current Imot of motor 521 represents a value of 63.2% of the span between the minimum value Ibot and the maximum value Itop of the actual current value of operating current Imot of motor 521. Note that this 63.2% ratio is a value (≈1 - 1 / e (e is the base of the natural logarithm)) used in calculating the time constant.

[0081] The torque detection unit 51, motor 521 and control device 53 are configured so that the period TP1 from time T21 when the torque signal SIG1 output from the torque detection unit 51 reaches a proportion Pr (a certain value) that is greater than the median and less than the maximum value Stop in the span SPN21 from the minimum value Sbot to the maximum value Stop of the torque signal SIG1, to time T22 when the operating current Imot of the motor 521 reaches said proportion Pr in the span SPN22 from the minimum value Ibot to the maximum value Itop, is shorter than 75 ms, which is half the cyclist's simple reaction time of 150 ms.

[0082] In this way, the torque detection unit 51, the motor 521, and the control device 53 are configured to have a response time that is faster than the simple reaction time. Therefore, the torque detection unit 51, the motor 521, and the control device 53 control the motor 521 based on the torque detected by the torque detection unit 51 at a speed that a human cannot simply react to. The torque detection unit 51, the motor 521, and the control device 53 are configured as a human augmentation system SYS1 that augments the capabilities of a human.

[0083] The ratio can be determined based on a level at which it can be determined that the actual measured value of the torque signal SIG or the actual current value of the operating current Imot of the motor 521 has sufficiently changed. This makes it possible to calculate the period from when the actual measured value of the torque signal has sufficiently changed until when the actual current value of the motor's operating current has sufficiently changed. Furthermore, the ratio used to determine the torque signal SIG1 and the ratio used to determine the operating current Imot of the motor 521 may be the same or different.

[0084] In the pedal bicycle 1, the control device 53 operates as described above when the cyclist actively operates the handlebars 332 of the steering unit 33 while pedaling the left and right pedals 41 in at least the extremely low speed range of the speed ranges divided into five sections: extremely low speed, low speed, medium speed, high speed, and very high speed. The extremely low speed may be the smallest speed range of the five equally divided speed ranges. The extremely low speed may include zero (km / s). For example, if the speed range is 0 to 60 km / s, the extremely low speed may be a speed range of 5 km / s or less, and the other sections, low speed, medium speed, high speed, and very high speed, may be speed ranges exceeding 5 km / s.

[0085] With the above-described configuration, the torque detector, the motor, and the control device can respond to disturbances within a period TP1 that is shorter than 75 ms, which is half the simple response time of 150 ms. Therefore, with the above-described configuration, the cyclist can respond to disturbances with high responsiveness that is sufficiently faster than the cyclist can feel the torque input from the road surface and operate the handlebars themselves.

[0086] In other words, the control device 53 can control the motor 521 to output a support torque based on the torque detection result by the torque detection unit 51 while increasing responsiveness to the torque signal output from the torque detection unit 51.

[0087] Furthermore, the control device 53 has a dead zone in the first section RNG11 in the supply pattern REL1 of the operating current I1 of the motor 521 corresponding to the torque signal SIG1. Therefore, when the input torque is small, the control device 53 controls the motor 521 so that it does not output torque. Even when torque is generated by an external force applied to the front wheel 21 while traveling on a well-paved road, it is expected that only a torque signal with a magnitude within the range of the first section RNG11 will be generated. Therefore, if the motor 521 outputs support torque within the range of the first section RNG11, it is expected that the pedal-equipped bicycle 1 will move slightly left and right.

[0088] With the above-described configuration, when traveling straight on a well-maintained paved road at the extremely low speed range, the increased responsiveness reduces the support torque transmitted from the motor 521 to the cyclist via the steering column 31 and the handlebars 332. Therefore, when traveling straight on a well-maintained paved road, it is possible to reduce the discomfort that the cyclist may feel when the vehicle body moves slightly left and right.

[0089] As described above, this pedaled bicycle 1 is suitable for bicycles in which a cyclist needs to respond to external disturbances while gripping the handlebars and pedaling the left and right pedals 41, and can support the cyclist in responding to such disturbances even while the cyclist is operating the vehicle left and right in accordance with the cyclist's pressure on the left and right pedals.

[0090] The control device may also operate as described above in response to the cyclist's operation in the four speed ranges of low speed, medium speed, high speed, and very high speed.

[0091] (Steering support when entering a rut) With reference to Figures 5 and 11, steering support when the front wheel 21 of the pedaled bicycle 1 enters a rut while the cyclist is maneuvering the vehicle body left and right in accordance with the cyclist's depressing of the left and right pedals 41 will be described. Figure 5 is a diagram illustrating steering support when entering a rut R1. Figure 11 is a schematic diagram illustrating steering support provided by the pedaled bicycle 1. The steering angle is the turning angle of the front wheel 21 relative to the center line CL of the vehicle in the left-right direction. The left side wall portion R11 of the rut R1 extends in a direction that intersects with the forward direction of the vehicle.

[0092] 5 and 11, in step S11, with the steering angle of the front wheel 21 at zero, the pedaled bicycle 1 enters the wheel rut R1 while tilting alternately left and right in accordance with the pressure applied to the left and right pedals 41. At this time, the motor 521 is not outputting support torque to the steering column 31.

[0093] Next, in step S12, the front wheel 21 comes into contact with the left wall portion R11 of the wheel rut R1. This generates a disturbance torque TQ1 that tends to rotate the front wheel 21 clockwise around the rotation axis P. Because the cyclist D1 is gripping the grips of the handlebars 332 of the steering unit 33 with his or her hands, the disturbance torque TQ1 applied to the front wheel 21 is transmitted to the cyclist D1's upper arm via the fork portion 32, the steering column 31, and the steering unit 33 (see FIG. 1 ). In response to this, a counter torque TQ2 is generated due to the inertia of the cyclist D1's upper arm, which counteracts the movement of the front wheel 21 that tends to rotate clockwise around the rotation axis P. In other words, a counter torque TQ2 that rotates counterclockwise around the rotation axis P is generated against this disturbance torque TQ1. The torque detection unit 51 detects the counter torque TQ2.

[0094] Next, in step S13, the control device 53 controls the motor 521 based on the detection result of the counter torque TQ2 by the torque detection unit 51. Specifically, the control device 53 controls the motor 521 to output a counterclockwise support torque TQ3 centered on the rotation axis P, for example, so that the counter torque TQ2 becomes zero. Note that the support torque TQ3 may be greater or smaller than the counter torque TQ2.

[0095] Because the front wheel 21 can maintain traction with the ground, the pedal bicycle 1 can climb over the left wall portion R11 of the rut R1, allowing the pedal bicycle 1 to continue traveling forward.

[0096] As described above, when the torque detection unit 51 detects a torque that causes the front wheels 21 to rotate clockwise about the rotation axis P relative to the steering unit 33 as viewed in one direction of the rotation axis, the control device 53 controls the motor 521 to generate a support torque TQ3 in the steering column 31 that causes the steering column 31 to rotate counterclockwise about the rotation axis P. The same is true vice versa. In other words, when the torque detection unit 51 detects a torque that causes the front wheels 21 to rotate counterclockwise about the rotation axis P relative to the steering unit 33 as viewed in one direction of the rotation axis, the control device 53 controls the motor 521 to generate a support torque TQ3 in the steering column 31 that causes the steering column 31 to rotate clockwise about the rotation axis P.

[0097] The control device 53 controls the steering support device 50 to output a support torque TQ3 corresponding to the force with which the cyclist grips the handlebars 332 when the front wheel 21 comes into contact with the left wall portion R11 of the rut R1, thereby suppressing an increase in the steering angle of the front wheel 21. In other words, it is possible to suppress a discrepancy between the yaw angle of the body frame 10 and the steering angle of the front wheel 21. This prevents the front wheel 21 from getting caught in the rut R1 and causing the vehicle body to roll inadvertently. Therefore, it is possible to support the cyclist D1 in responding to disturbances even while the cyclist D1 is operating the vehicle body left and right in accordance with his or her depression of the left and right pedals 41.

[0098] In the above-described configuration, the torque that causes the front wheels 21 to rotate relative to the steering unit 33 around the rotation axis P of the steering column 31 is generated at the moment an external force from the road surface is applied to the front wheels 21, and therefore can be detected more quickly than the roll angle or roll rate, which are physical quantities that are detected after the fact.

[0099] Furthermore, the control device 53 controls the steering of the motor 521 based on the torque detection result by the torque detection unit 51. With this configuration, the steering control of the motor 521 can be executed in response to the torque detection, even without detecting the tilt of the vehicle body. Therefore, with the above configuration, more preliminary measures can be taken in response to the torque detection. Therefore, for example, it is possible to respond to an external disturbance at an early stage.

[0100] Furthermore, while the cyclist D1 is manipulating the vehicle body in the left-right direction in accordance with the depression of the left and right pedals 41, the cyclist D1 performs an operation to tilt the vehicle body in the left-right direction, but does not perform an operation to rotate the steering unit 33 around the rotation axis P. Therefore, if torque of the front wheel 21 is detected during the vehicle body manipulation in the left-right direction, it is highly likely that this torque is due to a disturbance not intended by the cyclist D1.

[0101] By performing the control described above, if the front wheel 21 enters a rut or a bump in the road while riding, for example, and a torque that causes the front wheel 21 to rotate is generated due to an external disturbance that is not the intention of cyclist D1, a support torque that cancels the rotation of the front wheel 21 can be applied to the front wheel 21 via the motor 521.

[0102] As described above, in pedal bicycle 1, torque detection unit 51, motor 521, and control device 53 are configured as human capability augmentation system SYS1 that augments human capabilities. That is, when a cyclist of pedal bicycle 1 actively operates handlebars 332 while pedaling, at least at extremely low speeds, regardless of road surface conditions, straight-ahead driving, or turning, torque detection unit 51, motor 521, and control device 53 are configured to have enhanced responsiveness relative to the simple reaction time of a human cyclist so that the period TP1 from the point at which the torque signal SIG1 output from torque detection unit 51 reaches a rate Pr of a value greater than the median and less than the maximum value Stop of the span SPN21 from the minimum value Sbot to the maximum value Stop to the point at which the actual current value of operating current I1 of motor 521 reaches a rate Pr of its maximum value Itop is shorter than half of 150 ms, which is the simple reaction time of a human cyclist.

[0103] As a result, the human capability augmentation system SYS1 can control the output of support torque by the motor 521 based on the torque detected by the torque detection unit 51 at a speed that a human simply cannot react to. In other words, the control device 53 controlling the motor 521 based on the detection result of the torque detection unit 51 is much faster than the cyclist sensing a change in load due to an external disturbance and responding by operating the handlebars 332.

[0104] Therefore, for example, before the load received by the front wheel 21 due to an external disturbance causes the vehicle body to tilt, or at the beginning of the occurrence of the vehicle body tilt, the torque detection unit 51, motor 521 and control device 53 enable the motor 521 to generate a support torque in a direction that suppresses the vehicle body tilt due to the external disturbance, before the cyclist feels the load due to the external disturbance and operates the handlebars 332.

[0105] As a result, even when the cyclist is gripping the handlebars 332 and operating the vehicle left and right in accordance with the pressure on the left and right pedals 41, the cyclist can be supported in responding to external disturbances.

[0106] Furthermore, by having the supply pattern REL1, the control device 53 can further support the cyclist in responding to disturbances.

[0107] (Variation 1 of Embodiment 1) A pedaled bicycle 1A according to Variation 1 of Embodiment 1 of the present invention will be described with reference to Figure 6. Figure 6 is a diagram showing the schematic configuration of the stem mechanism 331 and steering support device 50 of the pedaled bicycle 1A according to Variation 1 of Embodiment 1 of the present invention. Note that in the following description of Variation 1, parts that are common to the pedaled bicycle 1 according to Embodiment 1 are given the same reference numerals and detailed description thereof will not be repeated.

[0108] As shown in FIG. 6 , the stem mechanism 331 includes the bicycle stem 100 , an anchor 75 , and a top cap 76 .

[0109] The handle holding portion 110 has a handle connecting portion (not shown) at one end thereof, to which the handle 332 is connected. The other end of the handle holding portion 110 is connected to the torque detection portion 51.

[0110] The steering column holding portion 120 has, at one end, a steering column connection portion 121. The steering column 31 is connected to the steering column connection portion 121. The other end of the steering column holding portion 120 is connected to the torque detection portion 51.

[0111] The motor 521 outputs a support torque to the steering column 31 via the torque transmission mechanism 522. In other words, the motor 521 and the torque transmission mechanism 522 constitute the actuator unit 52.

[0112] The motor 521 is a motor that outputs a support torque around the rotation axis Q of the motor.

[0113] The torque transmission mechanism 522 transmits the output of the motor 521 to the steering column 31. For example, the torque transmission mechanism 522 transmits the output of the motor 521 to the steering column 31, or transmits the torque from the steering column 31 to the motor 521. The torque transmission mechanism 522 may have any configuration, such as a gear, a link, a belt, or a chain, as long as it is capable of transmitting the torque of the motor 521 to the steering column 31. Furthermore, the torque transmission mechanism 522 may be configured to constantly transmit the output of the motor 521 to the steering column 31.

[0114] The motor 521 is located in front of the steering column 31. Although not specifically shown, the motor 521 is supported by the body frame 10 of the pedal bicycle 1A via a torque transmission mechanism 522.

[0115] The motor 521 may be located anywhere relative to the steering column 31, as long as it is located near the steering column 31, such as behind, to the left, or to the right of the steering column 31. Although not specifically shown, the motor 521 may be fixed to the head tube 11 by a stopper that restricts rotation of the motor 521 about the rotation axis P relative to the head tube 11 of the pedal-equipped bicycle 1A.

[0116] (Variation 2 of Embodiment 1) A pedaled bicycle 1B according to Variation 2 of Embodiment 1 of the present invention will be described with reference to Figure 7. Figure 7 is a flow chart illustrating steering assistance in response to steering by cyclist D1. Note that in the following description of Variation 2, parts that are common to the pedaled bicycle 1 according to Embodiment 1 are given the same reference numerals and detailed description will not be repeated.

[0117] 7, in step S21, with the steering angle of the front wheel 21 at zero, the pedaled bicycle 1B enters the wheel track R1 while tilting alternately left and right in accordance with the pressure on the left and right pedals 41. At this time, the motor 521 does not output any assist torque to the steering column.

[0118] In step S22, the cyclist D1 steers the handlebars 332 to rotate the steering column 31 counterclockwise around the rotation axis P. This generates a torque TQ21 that tends to rotate the front wheel 21 counterclockwise around the rotation axis P. In response to this, a counter torque TQ22 that opposes the movement of the front wheel 21 to rotate counterclockwise around the rotation axis P is generated in the front wheel 21 due to frictional force with the ground. The torque detection unit 51 detects the torque TQ21 that tends to rotate the front wheel 21 counterclockwise around the rotation axis P.

[0119] Next, in step S23, the control device 53 controls the motor 521 based on the detection result of the torque TQ21 by the torque detection unit 51. Specifically, the control device 53 controls the motor 521 so that the motor 521 outputs an assist torque TQ23 that tends to rotate the front wheel 21 counterclockwise about the rotation axis P.

[0120] As described above, when the torque detection unit 51 detects a torque that causes the steering unit 33 to rotate counterclockwise relative to the front wheels 21 around the rotation axis P as viewed in one direction of the rotation axis P, the control device 53 controls the motor 521 to output an assist torque to the steering column 31 in the counterclockwise direction around the rotation axis P based on the detected torque. Also, when the torque detection unit 51 detects a torque that causes the steering unit 33 to rotate clockwise relative to the front wheels 21 around the rotation axis P as viewed in one direction of the rotation axis P, the control device 53 controls the motor 521 to generate an assist torque to the steering column 31 in the clockwise direction around the rotation axis P based on the detected torque.

[0121] By such control by the control device 53, when torque from the steering unit 33 is detected, assistance can be provided in the direction intended by the cyclist D1.

[0122] The control device 53 may be configured to change the value of the torque output by the motor 521 in response to the magnitude of the torque detected by the torque detection unit 51. Such a control device 53 can perform control according to the size, structure, weight, type, use, etc. of the pedaled bicycle 1B by changing the support torque or assist torque output by the motor 521 in response to the magnitude of the torque detected by the torque detection unit 51. This makes it possible to support the cyclist in responding to disturbances even while maneuvering the bicycle body left and right in accordance with the cyclist's pressure on the left and right pedals.

[0123] The control device 53 may also be configured to maintain a constant support torque or assist torque output by the motor 521 relative to the magnitude of the torque detected by the torque detection unit 51. This reduces the amount of power consumed by the battery that drives the motor 521 and extends the time that assistance is possible. This makes it possible to assist or support the cyclist in responding to disturbances even while maneuvering the vehicle left or right in accordance with the cyclist's pressure on the left and right pedals.

[0124] (Third Modification of First Embodiment) A pedaled bicycle 1C according to a third modification of the first embodiment of the present invention will be described with reference to Figure 8. Figure 8 is a diagram illustrating the steering range. In the following description of the third modification, parts that are common to the pedaled bicycle 1 according to the first embodiment are given the same reference numerals and detailed description thereof will not be repeated.

[0125] As shown in FIG. 8, the range in which the motor 521 applies support torque to the steering column 31 is a range of 180 degrees or less within the rotation range of the steering unit 33 about the rotation axis P.

[0126] In other words, the range in which the motor 521 applies support torque to the steering column 31 is from a state in which the steering angle of the front wheels 21 is zero to +90° counterclockwise around the rotation axis P, and from a state in which the steering angle of the front wheels 21 is zero to +90° clockwise around the rotation axis P.

[0127] When cyclist D1 dismounts from pedaled bicycle 1C and is pushing pedaled bicycle 1C, the steering angle at which steering unit 33 is rotated around rotation axis P of steering column 31 is larger than when pedaled bicycle 1C is in a traveling state. This is due to the characteristics of pedaled bicycle 1C in that, when pedaled bicycle 1C is in a traveling state, corners are turned mainly by leaning the body, whereas when pedaled bicycle 1C is being pushed, the direction of travel is determined by the steering angle of steering unit 33.

[0128] According to the above-described configuration, when the pedal bicycle 1C is pushed forward, the motor 521 applies a support torque to the steering column 31 within a 180-degree range of rotation around the rotation axis P of the steering section 33.

[0129] This allows the pedal bicycle 1C to respond to external disturbances such as ruts even when the steering unit 33 is rotated in a wide range of directions while being pushed along. Also, the pedal bicycle 1C can respond to external disturbances even when traveling at low speeds.

[0130] While the embodiments of the present invention have been described above, the above-described embodiments are merely examples for carrying out the present invention. Therefore, the present invention is not limited to the above-described embodiments, and can be practiced by appropriately modifying the above-described embodiments within the scope of the spirit thereof.

[0131] In each of the above-described embodiments, the pedal bicycles 1, 1A, 1B, and 1C assist or support the steering of the cyclist D1 using a steering support device 50. However, the pedal bicycle may also have a pedaling force assist device that assists the pedaling force using an electric motor or the like.

[0132] In each of the above-described embodiments, the stem mechanism 331 is an ahead stem. However, the stem mechanism may be a threaded stem that is connected to the steering column by pressing a fixing member provided at the lower end against the inner surface of the upper part of the steering column.

[0133] In each of the above-described embodiments, the pedal bicycles 1, 1A, 1B, and 1C have a pine-needle-shaped fork 32 in which the left fork 321 and the right fork 322 are connected by a single connecting part 323. However, the pedal bicycle may have a fork in which the left fork 321 and the right fork 322 are connected by multiple connecting parts.

[0134] In each of the above-described embodiments, the torque detection unit 51 detects the torque between the steering unit 33 and the steering column 31. However, the torque detection unit 51 may also detect the torque between the steering column and the fork unit.

[0135] In the first variation of the first embodiment, the torque detector 51 is located in the front-to-rear direction relative to the steering column connection portion 121. However, the torque detector may also be located in the left-to-right direction relative to the steering column connection portion. In this case, the torque detector may be located in a position where at least a portion of the torque detector overlaps with the steering column connection portion when viewed from the left to right of the bicycle stem. Furthermore, the torque detector may be located so that a portion of the torque detector overlaps with the steering column holder when viewed from the front-to-rear direction of the bicycle stem.

[0136] In each of the above-described embodiments, the torque detection unit 51 is located in front of the steering column 31. However, the torque detection unit may be located behind the steering column, or may be located to the left or right of the steering column.

[0137] In each of the above-described embodiments, the steering column 31 extends in an oblique direction. However, the steering column 31 may extend in the vertical direction.

[0138] In each of the above embodiments, the current command generating unit 531 of the control device 53 generates the current command Icom based on the supply pattern REL1 of the operating current I1 of the motor 521 corresponding to the torque signal SIG1. However, the control device may have a plurality of types of supply patterns of the operating current of the motor corresponding to the torque signal.

[0139] 9, the plurality of supply patterns REL1, REL2 have different curves of the operating current I1 of the motor 521 at least in the region where the torque signal SIG1 is larger than the change regions REG1, REG2. The current command generating unit of the control device determines that, in the supply pattern REL2, the average rate of change of the operating current I1 of the motor in a first section RNG21 from zero to a predetermined value Th2 is smaller than the average rate of change of the operating current I1 of the motor in a second section RNG22 whose value is larger than the first section RNG21.

[0140] The current command Icom may be generated based on the supply pattern REL2 having a steeper gradient than the supply pattern REL1. More specifically, the average rate of change of the motor operating current I1 in the second section RNG22 in the supply pattern REL2 is greater than the average rate of change of the motor operating current I1 in the second section RNG12 in the supply pattern REL1 shown in FIG.

[0141] The above-described configuration can support responses to disturbances by supplying power in a pattern that corresponds to the riding situation, such as downhill riding on rough terrain (off-road), hill climbing on rough terrain (off-road), landing from a jump, carrying a heavy load on the front of a pedal bicycle, or carrying a child on a pedal bicycle.

[0142] For example, the supply pattern REL2 can output a larger support torque to the steering column than the supply pattern REL1. According to the above-described configuration, in the second section RNG22, a larger support torque can be output to the steering column, particularly at the stage when the detection unit 51 begins to detect torque exceeding the dead band. Therefore, according to the above-described configuration, a larger support force can be obtained.

[0143] Furthermore, as shown in FIG. 10 , the supply patterns REL31, REL32, and REL33 may include change regions REG21, REG22, and REG23 with different variations. At change point Th21 of supply pattern REL31, the operating current I1 of the motor 521 is not zero. As in change region REG21 of supply pattern REL31, the operating current I1 of the motor 521 relative to the torque signal SIG1 may increase in slope from a non-zero value at change point Th21. In supply pattern REL32, the value of the operating current I1 increases in an S-shaped manner. As in change region REG22 of supply pattern REL32, the value of the operating current I1 may increase significantly around point Th22, drawing a curve. As in change region REG23 of supply pattern REL33, the value of the operating current I1 may increase exponentially around point TH23.

[0144] The change region may be a point of change from a section where the rate of change is zero to a point where the rate of change becomes positive.The change region may be a section where the rate of change increases.

[0145] The plurality of power supply patterns may be manually switchable by the cyclist. The control device may automatically switch among the plurality of power supply patterns based on the road surface condition on which the pedaled bicycle is traveling or on a physical quantity related to the pedaled bicycle. The control device may acquire the road surface condition based on, for example, image information captured by a camera mounted on the pedaled bicycle or worn by the cyclist. The control device may also acquire the road surface condition based on information related to the location of the pedaled bicycle. The control device may acquire the location of the pedaled bicycle using a Global Navigation Satellite System (GNSS). The control device may estimate the road surface condition based on weather information. Examples of the physical quantity include torque detected by a torque detection unit, a frequency obtained by frequency analysis of the torque, or a peak frequency over a predetermined period.

[0146] The control device may also control the motor to output a torque in the opposite direction to the torque detected by the torque detection unit, depending on the magnitude of the torque. This allows a damper function to be achieved.

[0147] In each of the above embodiments, the average rate of change in the first interval RNG11 is zero. However, the average rate of change in the first interval does not have to be zero. This makes the operation of the motor in the first interval slower than in the second interval.

[0148] In each of the above embodiments, the current command generator 531 of the control device 53 generates the current command Icom based on the supply pattern REL1 of the operating current I1 of the motor 521 corresponding to the torque signal SIG1. However, the control device may also include a process for generating a current command by correcting a value obtained from a supply pattern in table format or function format. For example, the control device may acquire the road surface condition on which the pedal bicycle is traveling based on camera information, map information, or the like, and correct the value obtained from the supply pattern based on the acquired road surface information. The control device may also correct the value obtained from the supply pattern based on physical quantities related to the pedal bicycle. The process for generating a current command by the control device may also include a process for interpolating or extrapolating values ​​defined in the supply pattern.

[0149] 1, 1A, 1B, 1C Pedaled bicycle 21 Front wheel 22 Rear wheel 10 Body frame 11 Head tube 31 Steering column 32 Fork section 321 Left fork section 322 Right fork section 323 Connecting section 33 Steering section 331 Stem mechanism 332 Handle 41 Left and right pedals 411 Left pedal 412 Right pedal 50 Steering support device 51 Torque detection section 52 Actuator section 521 Motor 522 Torque transmission mechanism 53 Control device 531 Current command generation section 532 Voltage command generation section 55 Ammeter 7 Saddle 75 Anchor 76 Top cap 100 Bicycle stem 110 Handle holding section 120 Steering column holding section 121 Steering column connection section P Rotation axis Pr Ratio Q Rotation axis CL Center line N Neutral position A1 Arrow indicating pressing down on the left pedal A2 Arrow indicating pulling up the left part of the steering wheel A3 Arrow indicating pressing down on the right pedal A4 Arrow indicating pulling up the right part of the steering wheel REL1, REL2, REL31, REL32, REL33 Supply pattern REG1, REG21, REG22, REG23 Change area SYS1 Human capability augmentation system

Claims

1. A pedaled bicycle having: a steering column extending along the axial direction of a head tube included in a body frame and rotatably supported on the head tube; a front wheel supported by a fork portion connected to a lower part of the steering column in the vertical direction of the body frame; a steering unit connected to an upper part of the steering column in the vertical direction of the body frame and including a handle for steering the front wheel by rotating the steering column about the axis; a torque detection unit provided between the steering unit and the front wheel and detecting torque applied to the steering column in a rotational direction about the rotation axis; a motor outputting a support torque to the steering column, which is a torque about the rotation axis; and a control device controlling the output of the support torque by the motor based on the torque detected by the torque detection unit, wherein when the speed range of the pedaled bicycle is equally divided into an extremely low speed range, a low speed range, a medium speed range, a high speed range and an extremely high speed range, the torque detection unit, the motor and the control device are 1. A pedaled bicycle configured as a Human Augmentation System that enhances the ability of a human to control the motor based on the torque detected by the torque detection unit at speeds where a human cannot simply react, by increasing responsiveness so that the period from when a proportion Pr of a certain value between the median and the maximum value of a span from the minimum to the maximum value of the actual measured value of the torque signal output from the torque detection unit is reached to when the actual current value of the motor's operating current reaches said proportion Pr of its maximum value is less than half of a Simple Reaction Time (SRT) of 150 ms, when a cyclist of the pedaled bicycle actively operates the handlebars while pedaling, at least in the extremely low speed range, regardless of road surface conditions, and whether the bicycle is traveling straight or turning.

2. A pedaled bicycle as described in claim 1, wherein the control device includes a supply pattern that defines the relationship between the torque signal and the operating current of the motor, and the supply pattern defines a change region before and after which the rate of change of the operating current of the motor changes significantly when the torque signal is reduced from a certain value of the torque signal when the operating current of the motor is being output toward zero, so that the support torque of the motor transmitted to the cyclist becomes smaller or the frequency of occurrence of the support torque decreases when the cyclist actively operates the handlebars while pedaling straight ahead at least at an extremely low speed on a well-maintained paved road surface.

3. A pedaled bicycle as described in claim 1 or 2, wherein the control device includes a supply pattern that defines the relationship between the torque signal and the operating current of the motor, and the supply pattern defines a change region before and after which the rate of change of the operating current of the motor changes significantly when the value of the torque signal is increased from zero toward a certain value of the torque signal when the operating current of the motor is being output, so that the support torque of the motor transmitted to the cyclist increases when the front wheel is subjected to an external disturbance while the cyclist is holding the handlebars and pedaling straight ahead.

4. A pedaled bicycle as described in claim 3, wherein the control device includes a plurality of types of the supply patterns, and the plurality of supply patterns differ in the operating current of the motor at least in the region where the torque signal is larger than the change region.

5. A pedaled bicycle as described in claim 4, wherein the control device switches and controls the supply patterns of the multiple types of operating currents manually through operation by the cyclist, automatically based on the road conditions on which the pedaled bicycle is traveling, or automatically based on physical quantities related to the pedaled bicycle.

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