Tricycle front wheel steering optimization method and tricycle

Abstract

The invention discloses a tricycle front wheel steering optimization method, and relates to the technical field of vehicle steering, the tricycle front wheel steering optimization method comprises the following steps: firstly, obtaining the total mass # imgabs0 # of a tricycle body, calculating the load # imgabs1 # borne by a front wheel, calculating the static friction steering torque # imgabs4 # of the front wheel through the load # imgabs2 # and the radius # imgabs3 # of the front wheel, obtaining the dragging distance # imgabs5 # of the tricycle body, and obtaining the total mass # imgabs0 # of the tricycle body; the method comprises the following steps: acquiring a front extension angle # imgabs6 # of a vehicle body, calculating equivalent friction force # imgabs7 #, calculating static steering torque through the equivalent friction force, knowing that # imgabs8 # and # imgabs9 # are in direct proportion, adjusting # imgabs10 # to reduce the static steering torque # imgabs11 #, and adjusting # imgabs12 # to correspondingly adjust the static steering torque # imgabs13 # so as to achieve the purpose of adjusting the size of the static steering torque # imgabs14 #. The steering portability and the driving ability are improved, and the riding safety and the obstacle avoidance ability are guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle steering, and more specifically, to an optimization method for the front-wheel steering of a tricycle. In addition, the present invention also relates to a tricycle designed and produced by using the above-mentioned optimization method for the front-wheel steering of a tricycle. Background Art

[0002] The steering system of a motorcycle mainly consists of a steering handlebar, a steering head pipe, a triple clamp, front shock absorbers, and tires, etc. The steering of a motorcycle is cumbersome due to the interaction between the ground and the steering wheel and the internal friction of the steering system. The magnitude of the resistance moment fed back to the steering handlebar affects the magnitude of the operating force value of the vehicle by the driver.

[0003] Currently, the existing three-wheel motorcycles in the industry are cumbersome to operate during the steering process. A large amount of force needs to be applied when operating the handlebar to change the direction of the motorcycle, resulting in poor steering lightness performance. This not only increases the driving fatigue, but also has poor obstacle avoidance ability, posing a potential safety hazard during riding, affecting the use efficiency and convenience of the three-wheel motorcycle, as well as the riding and driving experiences.

[0004] In summary, how to provide a method for optimizing the front-wheel steering force before the production of a tricycle is an urgent problem to be solved by those skilled in the art at present. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide an optimization method for the front-wheel steering of a tricycle, which can determine its main dimensions during the production process of the tricycle, so as to achieve the purpose of reducing the force required for steering and improving the driving experience.

[0006] Another purpose of the present invention is to provide a tricycle designed and produced by using the above-mentioned optimization method for the front-wheel steering of a tricycle, which has the effect of reducing the force required for steering and improving the driving experience.

[0007] In order to achieve the above purpose, the present invention provides the following technical solutions:

[0008] An optimization method for the front-wheel steering of a tricycle, the tricycle including a vehicle body, a front wheel, and a steering shaft, comprising:

[0009] Obtaining the total mass of the vehicle body , and obtaining the radius of the position where the front wheel contacts the ground when the front wheel is stationary and in contact with the ground ;

[0010] Calculating the static friction steering torque of the front wheel through the total mass of the vehicle body and the radius ; ;

[0011] Obtaining the trail of the vehicle body , obtain the forward extension angle of the vehicle body ;

[0012] Based on the relationship between the radius and , obtain the equivalent frictional force ;

[0013] According to the relationship between the equivalent frictional force , the static steering torque and , adjust to achieve the purpose of reducing the static steering torque .

[0014] Furthermore, in the present invention, the calculation formula for the relationship between the equivalent frictional force and is: .

[0015] Furthermore, in the present invention, the calculation formula for the front wheel load is: , where is 9.8, is the front wheel load-bearing.

[0016] Furthermore, in the present invention, the calculation formula for the front wheel static friction steering torque is: , where is the front wheel air pressure, is the front wheel sliding friction coefficient.

[0017] Furthermore, in the present invention, the calculation formula for the equivalent frictional force is: .

[0018] Furthermore, in the present invention, obtain the offset of the vehicle body , the offset refers to the vertical distance between the axis of the steering shaft and the center of the front wheel. Calculate the scrub radius through the offset and the forward extension angle .

[0019] Furthermore, in the present invention, the relationship formula for the offset , the forward extension angle and the scrub radius is: .

[0020] Furthermore, in the present invention, the range of the scrub radius L is 0 mm to 30 mm.

[0021] A tricycle is designed and manufactured by using the above-mentioned tricycle front-wheel steering optimization method.

[0022] When the tricycle front-wheel steering optimization method provided by the present invention is used, first, the total mass of the vehicle body is obtained , and the load borne by the front wheels is calculated . Then, when the front wheels are stationary and in contact with the ground, the radius of the contact position between the front wheels and the ground is obtained . The contact position between the tire load and the ground is circular, and the radius is the radius of this circle. The static friction steering torque of the front wheels is calculated through the front-wheel load and the radius . The trail of the vehicle body is obtained. The trail is the distance from the intersection of the perpendicular line drawn from the front-wheel contact point to the front fork steering axis to the center of the front wheel. The caster angle of the vehicle body is obtained. The caster angle is the angle between the central axis of the steering shaft and the vertical line of the ground. The equivalent friction force is calculated through the relationship between the radius . The static steering torque is calculated through the equivalent friction force. It can be known that is proportional to . By adjusting , the static steering torque can be reduced. That is to say, by adjusting , the static steering torque is correspondingly adjusted to achieve the purpose of adjusting the magnitude of the static steering torque , improving the steering lightness and driving ability, and ensuring the riding safety and obstacle avoidance ability.

[0023] The present invention also relates to a tricycle designed and produced by using the above-mentioned tricycle front-wheel steering optimization method, which has the above-mentioned beneficial effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only the embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained according to the provided drawings without creative efforts.

[0025] Figure 1 It is a flow chart of the method provided by the present invention;

[0026] Figure 2Schematic structural diagram of the front wheel of the tricycle provided by the present invention;

[0027] Figure 3 Schematic structural diagram of the front wheel when it touches the ground as viewed from below in the present invention;

[0028] Figures 1 - 3 In the figure, the reference numerals include:

[0029] 1, vehicle body; 2, steering shaft; 3, front wheel. Detailed implementation manners

[0030] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0031] The core of the present invention is to provide an optimization method for the front-wheel steering of a tricycle, which can determine its main dimensions during the production process of the tricycle, so as to reduce the force required for steering and improve the driving experience.

[0032] The core of the present invention is to provide a tricycle designed and produced by using the above-mentioned optimization method for the front-wheel steering of a tricycle, which has the effect of reducing the force required for steering and improving the driving experience.

[0033] Please refer to Figures 1 - 3 , an optimization method for the front-wheel steering of a tricycle, the tricycle includes a vehicle body 1, a front wheel 3 and a steering shaft 2, wherein the front wheel 3 is rotatably installed on the steering shaft 2, the steering shaft 2 is rotatably connected to the vehicle body 1, and there is a preset included angle between the axis of the steering shaft 2 and the front wheel 3; the optimization method for the front-wheel steering of a tricycle includes the following steps:

[0034] Step S1, take the total mass of the vehicle body 1 , and obtain the radius of the position where the front wheel (3) contacts the ground when the front wheel 3 is stationary and in contact with the ground ;

[0035] Step S2, obtain the static friction steering torque of the front wheel (3) through the total mass of the vehicle body (1) and the radius ; ;

[0036] Step S3, obtain the trail of the vehicle body (1) , and obtain the caster angle of the vehicle body (1) ;

[0037] Step S4, through the radius and to obtain the equivalent frictional force based on the relationship ;

[0038] Step S5: According to the equivalent frictional force , the static steering torque and to adjust so as to achieve the purpose of reducing the static steering torque .

[0039] During use, first obtain the total mass of the vehicle body 1 , and calculate the load borne by the front wheels 3 . Then, when the front wheels 3 are stationary and in contact with the ground, obtain the radius of the contact position between the front wheels 3 and the ground . The contact position between the tire load and the ground is circular, and the radius is the radius of this circle. Calculate the static frictional steering torque of the front wheels 3 through the load of the front wheels 3 and the radius . Obtain the trail of the vehicle body 1. The trail is the distance from the intersection of the perpendicular line drawn from the ground contact point of the front wheels 3 to the front fork steering axis 2 line to the center of the front wheels 3. Obtain the caster angle of the vehicle body 1. The caster angle is the angle between the central axis of the steering axis 2 and the vertical line of the ground. Calculate the equivalent frictional force through the relationship between the radius , and calculate the static steering torque through the equivalent frictional force. It can be known that is proportional to . Adjust to achieve the reduction of the static steering torque . That is to say, by adjusting , the static steering torque is correspondingly adjusted to achieve the purpose of adjusting the magnitude of the static steering torque , improving steering lightness and driving ability, and ensuring riding safety and obstacle avoidance ability.

[0040] It should be noted that in the embodiments of the present invention, the acquisition method of the ground contact area of the front wheels 3 can be selected to place the front wheels 3 above a transparent material for convenient measurement and acquisition.

[0041] Optionally, in some embodiments, the calculation formula for the relationship between the equivalent frictional force and is: , By substituting the above respective data, the relationship with the static steering torque can be obtained.

[0042] Optionally, in some embodiments, the total mass of the vehicle body 1 is the load borne by the front wheels 3 plus the load borne by the rear wheels. Specifically, the load ratio of the front wheels 3 to the rear wheels is related to the number of wheels. Finally, the load borne by the front wheels 3 plus the load m h borne by the rear wheels is the total mass of the vehicle body 1. Optionally, in some embodiments, the load of the front wheels 3 is calculated by the formula: , where is 9.8, and the load of the front wheels 3 is obtained from the weighed mass of the front wheels 3.

[0043] Optionally, in some embodiments, the static friction steering torque of the front wheels 3 is calculated by the formula: , where is the air pressure of the front wheels 3, and f is the sliding friction coefficient of the front wheels 3. That is, after obtaining the load of the front wheels 3, the air pressure of the front wheels 3 is obtained, and by substituting into the formula, the static friction steering torque of the front wheels 3 can be calculated.

[0044] Optionally, in some embodiments, is 0.7, that is, the static friction coefficient of the front wheels 3 is 0.7, is 0.25 Mpa, that is, the air pressure of the front wheels 3 is 0.25 Mpa. Vehicles of different models can monitor the air pressure value in real time according to the actual situation.

[0045] Optionally, in some embodiments, the equivalent frictional force is calculated by the formula: ,

[0046] It should be noted that the equivalent frictional force in the embodiments of the present invention is a concept that often appears in physical problems. It refers to the fact that in some cases, a complex frictional force system can be simplified into an equivalent single frictional force for processing. The magnitude and direction of this equivalent frictional force are the same as the resultant force of all the frictional forces in the original system.

[0047] Optionally, in some embodiments, the offset of the vehicle body 1 is obtained. The offset refers to the vertical distance between the line of the front fork steering shaft 2 and the center of the front wheels 3. Through the offset and the rake angle The drag distance is calculated , and the drag distance ranges from 0 mm to 30 mm. The drag distance can be selected according to various data before vehicle production to achieve the purpose of making the vehicle have a lighter steering feel.

[0048] Optionally, in some embodiments, through the offset distance , the caster angle and the drag distance , the relational formula is: . Through the above formula, the drag distance or the offset distance can be calculated.

[0049] The following are experimental examples:

[0050] The geometric parameters of a certain motorcycle model are as follows:

[0051] Tricycle parameter items Parameter value Total vehicle mass kg 590 Front wheel 3 load kg 271 Rear wheel load kg 319 Caster angle ° 22 Trail mm 26 Offset mm 82.6

[0052] The calculation formula for the static friction steering torque of the tire is as follows:

[0053]

[0054] In the formula:

[0055] is the load on the front wheel 3, , where 50 kg is the load of the 75 kg occupant allocated to the front wheel 3; is the tire pressure, = 0.25 MPa; is the sliding friction coefficient, = 0.7.

[0056] According to the above formula, the static friction steering torque of the tire is calculated, and at the same time, the radius of the tire contact area can be obtained.

[0057] According to ;

[0058] the total equivalent frictional force is obtained;

[0059] Then the steering torque transmitted from the static frictional torque to the steering shaft 2 is:

[0060]

[0061] In the formula: the drag distance is 26 mm, and α is the caster angle of 22°.

[0062] At this time, the caster angle is optimized from 22° to 21°, and the offset distance is optimized from 81.474 mm to 83.02 mm. Then the steering torque transmitted from the ground static friction torque to the steering shaft 2 is as follows:

[0063]

[0064] The required effective steering torque is 86.74 N·m, which is reduced by 34.79 N·m, and the optimization efficiency is 27.9%.

[0065] Therefore, by adopting the optimization method of the present application, the optimal values of the caster angle and the offset distance of the vehicle can be clearly obtained, so that the vehicle has good experience and operation safety, and significantly improves the steering lightness of the tricycle.

[0066] That is to say, the key point of the embodiment of the present invention is: obtained by formula calculation is proportional to and by adjusting the magnitude can achieve the purpose of reducing the static steering torque That is to say, by adjusting the static steering torque is correspondingly adjusted to achieve the purpose of adjusting the magnitude of the static steering torque to improve the steering lightness and driving ability, ensure the riding safety and obstacle avoidance ability, and can achieve an optimization effect of nearly 30%, that is, save one-third of the power required for steering, and significantly improve the steering lightness of the tricycle.

[0067] The various embodiments in this specification are described in a progressive manner. The key points of each embodiment are the differences from other embodiments. The same and similar parts between the various embodiments can be referred to each other.

[0068] The above has introduced in detail a method for optimizing the front-wheel steering of a tricycle provided by the present invention. Specific examples are used in this article to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and modifications can still be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A method for optimizing front wheel steering of a tricycle, the tricycle comprising a vehicle body (1), a front wheel (3) and a steering shaft (2), characterized in that: include: Get the total mass of the vehicle body (1) , obtaining the radius of the contact position between the front wheel (3) and the ground when the front wheel (3) is stationary and grounded ; The total mass of the vehicle body (1) and the radius Get the static friction steering torque of the front wheel (3) ; Obtain the drag distance of the vehicle body (1) , obtain the forward angle of the vehicle body (1) ; Through the radius and The equivalent friction force is obtained ; According to the equivalent friction , Static steering torque and relationship, adjust To reduce the static steering torque purpose.

2. A tricycle front wheel steering optimization method according to claim 1, characterized in that: The equivalent friction force and The relationship is calculated as: .

3. A tricycle front wheel steering optimization method according to claim 2, characterized in that: The front wheel (3) load The calculation formula is: ,in is 9.8, The front wheel (3) bears the load.

4. A tricycle front wheel steering optimization method according to claim 1, characterized in that: The front wheel (3) static friction steering torque The calculation formula is: ,in is the air pressure of the front wheel (3), is the sliding friction coefficient of the front wheel (3).

5. A tricycle front wheel steering optimization method according to claim 1, characterized in that: The equivalent friction force The calculation formula is: .

6. A method for optimizing front wheel steering of a tricycle according to any one of claims 1 to 5, characterized in that: Get the offset distance of the vehicle body (1) , the offset distance It refers to the vertical distance between the axis of the steering shaft (2) and the wheel center of the front wheel (3), which is measured by the offset distance and protrusion angle The drag distance is calculated .

7. A tricycle front wheel steering optimization method according to claim 6, characterized in that: The offset , the protrusion angle and the drag distance The relationship formula is: .

8. A method for optimizing front wheel steering of a tricycle according to claim 7, characterized in that: The drag distance L ranges from 0 mm to 30 mm.

9. A tricycle, characterized in that: The front wheel steering optimization method of a three-wheeled vehicle described in any one of claims 1 to 8 is adopted for design and manufacture.

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