Vehicle ultimate garage entering and exiting method

Abstract

The invention relates to the field of vehicle automatic control, in particular to a vehicle ultimate in-out method, which comprises the following steps of: judging whether a vehicle has an out-of-garage condition or not; if yes, the one-key car moving function is activated, the ABS, the TCS and the driving anti-skid function are temporarily closed, meanwhile, a steering wheel is controlled to hit to the bottom towards the steering side, and wheels on the inner side of steering are locked; the front wheel driving torque is controlled to make the wheel end driving force break through the road surface limit adhesive force, so that the front wheel slips, and the vehicle rotates with the inner side rear wheel as the circle center; and when the preset expected angle is reached, driving is stopped, and wheel braking is locked. According to the invention, parking-out assistance for assisting in parking-out of the vehicle is executed according to the surrounding condition of the vehicle, automatic parking and parking-out are realized, tedious operation is avoided, and the convenience of using the vehicle by a user is improved; and in the warehouse-out process, the execution speed of the warehouse-out action can be judged, so that the discomfort of passengers is reduced, and meanwhile, the stability and safety of operation are also improved.

Description

Technical Field

[0001] The invention relates to the technical field of vehicle automatic control, and in particular to a method for limiting vehicle entry and exit. Background Art

[0002] The number of vehicles is increasing year by year. In today's world of limited parking resources, the size of vehicles is getting bigger and bigger, which makes parking more difficult. After parking in a parallel position, when you are ready to drive away, you often find that the vehicles in front and behind are too close to your car, and it is difficult to move out due to limited space. In this case, even experienced drivers need to move the vehicle several times before they can move it out. The operation is very inconvenient and it is easy to cause scratches. Therefore, how to automatically and intelligently control the vehicle so that the vehicle can be automatically, quickly and safely moved out of the parking space in a limited space is a problem that technicians in this field need to consider. Summary of the invention

[0003] The purpose of the present invention is to provide a method for limiting vehicle entry and exit, so as to solve the problem in the prior art that vehicles are difficult to exit due to space limitations.

[0004] The technical solution of the present invention is: a method for limiting vehicle entry and exit, comprising the following steps:

[0005] S1. Activate the one-button vehicle moving function to determine whether the vehicle is ready to leave the warehouse. The determining factors include the distance to the vehicle in front and the obstacles around the vehicle.

[0006] S2. If the conditions for leaving the warehouse are met, temporarily turn off the ABS, TCS and drive anti-skid functions. At the same time, turn the steering wheel to the bottom to the steering side to lock the inner wheel.

[0007] S3, controlling the front wheel drive torque so that the wheel end drive force exceeds the road surface's limit adhesion, thereby causing the front wheel to slip and causing the vehicle to rotate with the inner rear wheel as the center;

[0008] S4. When the preset desired angle is reached, drive and lock wheel brakes are stopped, but braking force is provided to keep the vehicle stationary until the driver takes over.

[0009] Preferably, in step S1, the distance D between the vehicle and the preceding vehicle or the preceding obstacle is determined according to the distance of the vehicle's detector to the obstacle around the vehicle. min ;

[0010] D min >L max -L;

[0011] Among them, L max is the longest distance from the vehicle body to the wheel, which is the distance from the left rear wheel to the right front end of the vehicle body or the distance from the right rear wheel to the left front end of the vehicle body; L is the distance from the front end of the vehicle body to the rear axle; Dmin It is the distance between the front end of the vehicle and the vehicle in front or the obstacle in front.

[0012] Preferably, in steps S2 and S3, the required driving force F is calculated according to the vehicle weight. p ;

[0013] F p =0.5·fmg;

[0014] Among them, f is the calibration coefficient, which is greater than 1 by default; m is the vehicle mass; and g is the gravity coefficient.

[0015] Preferably, when performing the rotation out of the warehouse action, the following conditions must be met at the same time:

[0016] V FL >max(V RL , V RR );

[0017] V FR >max(V RL , V RR );

[0018] min(V RL , V RR )=0;

[0019]

[0020] Among them, V FL is the left front wheel speed, in m / s; V FR is the right front wheel speed, in m / s; V RL is the left rear wheel speed, in m / s; V RR is the right rear wheel speed, in m / s; ω is the yaw angular velocity; d wheel is the wheel spacing.

[0021] Preferably, in step S4, the angle of rotation of the vehicle is calculated And judge whether they all reach the expected angle

[0022]

[0023] Among them, t0 is the rotation start time; t is the current time;

[0024]

[0025] Among them, d axle is the wheelbase of the vehicle.

[0026] Preferably, in step S3, it can be determined whether the front axle speed is too fast according to the slip rate, and if it is too fast, the front axle drive is torque-limited according to the front wheel slip rate;

[0027]

[0028] Where Sr is the slip ratio, which is greater than 10.

[0029] Preferably, in step S1, it is also necessary to determine whether the vehicle's driving system, braking system and steering system meet the requirements for functional enablement.

[0030] Compared with the prior art, the advantages of the present invention are:

[0031] (1) The use basis of the present invention is relatively simple, and it is applicable to front-wheel drive or four-wheel drive vehicles that limit the rear axle driving torque. By performing out-of-parking assistance based on the positional relationship with obstacles around the vehicle and the surrounding conditions of the vehicle, automatic parking and out-of-parking are achieved, which avoids cumbersome operations and improves the convenience of users' use of the vehicle. In addition, during the out-of-parking process, the speed of the out-of-parking action can be judged and executed, so that the discomfort of passengers is reduced, and the stability and safety of the operation are also increased. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0033] Figure 1 This is a schematic flow chart of the method for limiting vehicle entry and exit according to the present invention;

[0034] Figure 2 This is a schematic diagram of the process of executing the vehicle extreme exit operation according to the present invention;

[0035] Figure 3 It is a schematic diagram of the process of the vehicle extreme exit from the warehouse according to the present invention. DETAILED DESCRIPTION

[0036] The present invention is further described in detail below in conjunction with specific embodiments:

[0037] like Figure 1-Figure 3 As shown, the present invention is applied to assisting the vehicle to exit the parking space after parking sideways. By detecting the position of obstacles in front of, behind and to the side of the vehicle, it is determined whether the vehicle can exit the parking space automatically. When exiting the parking space, the front wheel drive is controlled, and the rear wheel rotates with the inner wheel as the center to control the vehicle to slip and rotate, so as to achieve the purpose of rotating the head of the vehicle out of the parking space. Specifically: A method for vehicle extreme entry and exit, comprising the following steps:

[0038] Activate the one-button vehicle moving function to determine whether the vehicle is ready for leaving the warehouse. The judgment factors include the distance to the vehicle in front, the obstacles around the vehicle body, and the size parameters of the vehicle itself. In this embodiment, the distance between the vehicle and the vehicles in front and behind, and the obstacles on the side of the vehicle can be measured based on the detector on the vehicle. Among them, the spacing of the obstacles on the side of the vehicle can be judged based on the driver's observation and estimation. In addition, it is generally only necessary to judge the distance to the vehicle in front. The distance to the rear vehicle gradually increases during the process of rotating out of the warehouse, that is, the parking position is the maximum distance. Therefore, in theory, the distance between the vehicle and the rear vehicle can be greater than zero. In actual operation, the driver needs to make a simple judgment due to the modification of the vehicle end, decorative parts and other factors.

[0039] The distance D between the vehicle and the vehicle or obstacle in front of it min , should meet: D min >L max -L, that is, the vehicle will not interfere with the vehicles in front and behind when rotating.

[0040] Among them, L max is the longest distance from the vehicle body to the wheel, which is the distance from the left rear wheel to the right front end of the vehicle body or the distance from the right rear wheel to the left front end of the vehicle body; L is the distance from the front end of the vehicle body to the rear axle; D min It is the distance between the front end of the vehicle and the vehicle in front or the obstacle in front.

[0041] Of course, before executing the departure, it is also necessary to determine whether the vehicle's drive system, braking system and steering system meet the functional enablement requirements.

[0042] If the conditions for leaving the warehouse are not met, the vehicle moving function cannot be activated.

[0043] If the conditions for leaving the warehouse are met, temporarily turn off the ABS, TCS and drive anti-skid functions, and stop activating the vehicle stability function. At the same time, according to the direction of the required departure, control the steering wheel to the steering side to the bottom, and lock the inner wheel. In this step, first calculate the driving force F required to drive the body rotation based on the vehicle weight. p , controlling the front wheel drive torque so that the wheel end drive force breaks through the road surface's limit adhesion, causing the front wheel to slip and the vehicle to rotate with the inner rear wheel as the center.

[0044] F p =0.5·fmg;

[0045] Among them, f is the calibration coefficient, which is greater than 1 by default; m is the vehicle mass; and g is the gravity coefficient.

[0046] When performing the rotation out of the warehouse action, the following conditions must be met at the same time:

[0047] V FL >max(V RL, V RR );

[0048] V FR >max(V RL , V RR );

[0049] min(V RL , V RR )=0;

[0050]

[0051] Among them, V FL is the left front wheel speed, in m / s; V FR is the right front wheel speed, in m / s; V RL is the left rear wheel speed, in m / s; V RR is the right rear wheel speed, in m / s; ω is the yaw angular velocity; d wheel is the wheel spacing.

[0052] When the vehicle rotates with the inner rear wheel as the center, the front wheel slips, that is, the wheel speed far exceeds the outer rear wheel speed. The inner wheel speed is zero. The wheel speed of the outer rear wheel should be equal to the product of the vehicle's rotational angular velocity and the wheel width of the two rear wheels. However, in actual operation, due to factors such as ground friction and uneven weight distribution after the vehicle is loaded, the wheel speed of the outer rear wheel and the product of the vehicle's rotational angular velocity and the wheel width of the two rear wheels cannot be stably equal, but are in dynamic balance. Therefore, the above formula can be calculated as: (V RL , V RR ).

[0053] On the premise of confirming the vehicle's rotation, the angle the vehicle has rotated is calculated based on the integral of the rotation angular velocity. When the preset desired angle is reached, the drive and locking wheel brakes are stopped, but the braking force to keep the vehicle stationary is provided until the driver takes over.

[0054] And judge whether they all reach the expected angle for:

[0055]

[0056] Among them, d axle is the wheelbase of the vehicle.

[0057] Calculate the angle of vehicle rotation The method is:

[0058]

[0059] Among them, t0 is the start time of rotation; t is the current time.

[0060] In this embodiment, in order to further ensure the riding experience of passengers and enable the driver to quickly intervene in the control of the vehicle in occasional situations, it is possible to determine whether the front axle speed is too fast according to the slip rate. If it is too fast, the front axle drive is torque-limited according to the front wheel slip rate to reduce the rotation speed of the vehicle.

[0061]

[0062] Wherein, Sr is the slip ratio, which is generally set to be greater than 10 and less than 20.

[0063] It should be noted that when the vehicle is parked sideways into a garage, the above method can also be used for automatic operation, and the direction of the rotational movement of the vehicle can be driven in the opposite direction.

[0064] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with this technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the scope of protection of the present invention. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is limited by the attached claims rather than the above description, and it is intended to include all changes within the meaning and scope of the equivalent elements of the claims in the present invention.

Claims

1. A method for limiting vehicle entry and exit, characterized in that: The following steps are involved: S1. Activate the one-button vehicle moving function to determine whether the vehicle is ready to leave the warehouse. The determining factors include the distance to the vehicle in front and the obstacles around the vehicle. S2. If the conditions for leaving the warehouse are met, temporarily turn off the ABS, TCS and drive anti-skid functions. At the same time, turn the steering wheel to the bottom to the steering side to lock the inner wheel. S3, controlling the front wheel drive torque so that the wheel end drive force exceeds the road surface's limit adhesion, thereby causing the front wheel to slip and causing the vehicle to rotate with the inner rear wheel as the center; S4. When the preset desired angle is reached, drive and lock wheel brakes are stopped, but braking force is provided to keep the vehicle stationary until the driver takes over.

2. A method for limiting vehicle entry and exit according to claim 1, characterized in that: In step S1, the distance D between the vehicle and the front vehicle or the front obstacle is determined based on the distance of the vehicle's detector to the obstacle around the vehicle. min ; D min >L max -L; Among them, L max is the longest distance from the vehicle body to the wheel, which is the distance from the left rear wheel to the right front end of the vehicle body or the distance from the right rear wheel to the left front end of the vehicle body; L is the distance from the front end of the vehicle body to the rear axle; D min It is the distance between the front end of the vehicle and the vehicle in front or the obstacle in front.

3. A method for limiting vehicle entry and exit according to claim 1, characterized in that: In steps S2 and S3, the required driving force F is calculated based on the vehicle weight. p ; F p =0.5·fmg; Among them, f is the calibration coefficient, which is greater than 1 by default; m is the vehicle mass; and g is the gravity coefficient.

4. A method for limiting vehicle entry and exit according to claim 3, characterized in that: When performing the rotation out of the warehouse action, the following conditions must be met at the same time: V FL >max(V RL ,V RR ); V FR >max(V RL ,V RR ); min(V RL ,V RR )=0; Among them, V FL is the left front wheel speed, in m / s; V FR is the right front wheel speed, in m / s; V RL is the left rear wheel speed, in m / s; V RR is the right rear wheel speed, in m / s; ω is the yaw angular velocity; d wheel is the wheel spacing.

5. A method for limiting vehicle entry and exit according to claim 4, characterized in that: In step S4, the angle of vehicle rotation is calculated And judge whether they all reach the expected angle Among them, t0 is the rotation start time; t is the current time; Among them, d axle is the wheelbase of the vehicle.

6. A method for limiting vehicle entry and exit according to claim 5, characterized in that: In step S3, it can be determined whether the front axle speed is too fast according to the slip rate. If it is too fast, the front axle drive is torque-limited according to the front wheel slip rate. Where Sr is the slip ratio, which is greater than 10.

7. A method for limiting vehicle entry and exit according to claim 6, characterized in that: In step S1 , it is also necessary to determine whether the vehicle's driving system, braking system and steering system meet the requirements for functional enablement.

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