CN111717299A - Vehicle self-stabilizing cockpit and control system and method based on the same - Google Patents

Abstract

The invention belongs to the field of vehicles, and in particular relates to a self-stabilizing cockpit of a vehicle and a control system and method based on the cockpit. It includes a cockpit with rotational degrees of freedom in pitch and roll directions, a cockpit carrier, a motor and a motor controller. There are two sets of motors and motor controllers, which respectively control the attitude of the cockpit in pitch and roll directions. Pitch control The motor is connected to the cockpit through a worm gear transmission mechanism that can realize one-way self-locking function, and the roll control motor is connected to the cockpit carrier through a worm gear and worm transmission mechanism; force sensors are set on the tires, and roll and pitch are set on the cockpit Angular velocity sensor. The present invention adjusts the attitude of the cockpit in real time through the motor, avoids excessive changes in the angle of roll and pitch of the cockpit, greatly reduces the impact of road bumps on the cockpit, and improves the driver's ability to adapt to complex off-road roads; The worm gear realizes the stability control function of the self-stabilizing cockpit.

Description

Vehicle self-stabilizing cockpit and control system and method based on the same

technical field

The invention belongs to the field of vehicles, and in particular relates to a self-stabilizing cockpit of a vehicle and a control system and method based on the cockpit.

Background technique

The most important performance requirement of off-road special vehicles is to be able to pass through harsh off-road roads at high speed. When off-road special vehicles drive on uneven roads at high speed, roll and pitch motions will occur. Excessive roll and pitch motions will seriously affect the driver's handling ability, and even cause drivers to make mistakes in judgment, making off-road special vehicles The physical or psychological sense of security is greatly reduced, so that the off-road mobility due to special vehicles cannot be exerted, and the task completion efficiency of off-road special vehicles is seriously reduced. At present, on off-road vehicles, the off-road maneuverability of the vehicle is mainly improved by optimizing the suspension or stabilizer bar system. However, the improvement of the performance of the suspension and stabilizer bar system is limited by the control stroke and torque capacity, and the vehicle body can only be reduced to a certain extent. It is difficult to cope with the severe driving conditions where the vehicle rolls and pitches greatly. Therefore, the innovative design of the self-stabilizing cockpit system of off-road special vehicles can eliminate the influence of vehicle roll and pitch on the driver's handling ability, so as to give full play to the adaptability of off-road special vehicles to harsh off-road roads.

The Chinese invention patent application "An aerial work vehicle with a self-stabilizing system and its self-stabilizing control method" (Application No.: CN201610938477.3, publication date: 2017.05.10), discloses an aerial work vehicle with a self-stabilizing system A self-stabilizing control method thereof, the self-stabilizing system of the aerial work vehicle comprises a vehicle body assembly, a boom support, a boom assembly, a hydraulic support foot, a balance counterweight device, a control box, a horizontal variable distance displacement sensor of the hydraulic support leg, an arm Luffing angle sensor and boom luffing cylinder pressure sensor, etc. The system controls the movement of the balance weight to generate a stable torque through the feedback of each sensor. However, the problem of this self-stabilizing system is that the response speed of the balance weight is slow, and it cannot cope with the body movement of the high-mobility off-road special vehicle.

In a word, the problems existing in the prior art are: the self-stabilizing system is designed for the change of the center of gravity caused by the lifting process of the aerial work vehicle, and cannot adapt to the roll and pitch motion control caused by the high-speed maneuvering of the high-mobility off-road special vehicle. demand, its real-time can not meet the control demand.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a vehicle self-stabilizing cockpit and a control system and method based on the cockpit.

The technical solution for realizing the purpose of the present invention is: a self-stabilizing cockpit of a vehicle, comprising a cockpit and a cockpit carrier with rotational degrees of freedom in pitch and roll directions;

The cockpit itself has a rotational degree of freedom in the pitch direction, and the cockpit carrier provides the cockpit with a rotational degree of freedom in the roll direction.

Further, it also includes a pitch control mechanism for controlling the rotational degree of freedom in the pitch direction of the cockpit, and a roll control mechanism for controlling the rotational degree of freedom in the roll direction of the cockpit.

Further, the pitch control mechanism includes a pitch motor controller, a first worm gear transmission mechanism with a self-locking function, and a pitch control motor;

The pitch control motor is connected to the cockpit through a first worm gear transmission mechanism capable of realizing a one-way self-locking function, and the pitch motor controller is used to control the pitch control motor.

Further, the roll control mechanism includes a roll motor controller, a second worm gear transmission mechanism with a self-locking function, and a roll control motor;

The roll control motor is connected to the cockpit carrier through a second worm gear transmission mechanism capable of realizing a one-way self-locking function, and the roll motor controller is used to control the roll control motor.

Further, the number of heads of the worms of the first and second worm gear transmission mechanisms z ₁ =1 and the lead angle on the cylindrical worm satisfies γ≦3°30′.

Further, the cockpit and the cockpit carrier and the cockpit carrier and the vehicle body are connected by bearings.

Further, the self-stabilizing cockpit is a symmetrical structure to avoid movement interference during the adjustment process.

A control system based on the above-mentioned cockpit, wherein force sensors are arranged on the tires of the vehicle, and roll and pitch angular velocity sensors are arranged on the cockpit to provide vehicle parameter input for the self-stable control system;

The control system includes a control threshold calculation module, a self-stabilization control module and an executive motor module;

The control threshold calculation module takes the vertical force of the four tires as the input quantity, and calculates the control threshold Flag according to the vertical force analysis of the four tires;

The self-stabilizing control module takes the control threshold Flag and the dynamic parameters of the cockpit as input, designs a control algorithm in combination with the dynamic equation of the cockpit, and outputs the corrected torque T* of the attitude of the cockpit;

The executive motor module includes a pitch motor controller, a first worm gear transmission mechanism, a pitch control motor, a second worm gear transmission mechanism, a roll motor controller, and a roll control motor.

A method for self-stabilizing control by utilizing the above-mentioned control system, comprising the following steps:

Step (1): the force sensor on the vehicle tire provides the vertical force of the four tires for the control threshold calculation module, and the control threshold calculation module calculates the control threshold Flag according to the vertical force analysis of the four tires;

Step (2): the self-stabilization control module takes the control threshold Flag and the dynamic parameters of the cockpit as input, designs a control algorithm in combination with the dynamic equation of the cockpit, and outputs the corrected torque T* of the cockpit attitude;

Step (3): Finally, the pitch control motor and the roll control motor are controlled by the pitch motor controller and the roll motor controller to drive the worm gear transmission mechanism to correct the cockpit attitude in real time.

Further, when Flag=0, the self-stabilization control module does not work, and the pitch control motor and roll control motor do not exert force on the cockpit; when Flag=1, the self-stabilization control module works, and the pitch control motor and roll control motor are real-time. Corrected cockpit attitude.

Compared with the prior art, the present invention has the following significant advantages:

(1) High mobility: The existing technology improves the off-road mobility of the vehicle through the suspension system, but the improvement of the suspension system is limited by the suspension control stroke and torque capacity. The self-stabilizing cockpit system adjusts the attitude of the cockpit in real time through the motor to avoid excessive changes in the roll and pitch angles of the cockpit, thereby greatly reducing the impact of road bumps on the cockpit, and improving the driver's ability to handle complex off-road roads. It is especially beneficial for the driver to maximize the power of off-road special vehicles and enhance the off-road mobility of off-road special vehicles.

(2) High reliability: The self-stabilizing cockpit system uses the motor to drive the worm gear with one-way self-locking function to adjust the attitude of the cockpit in real time. When the vehicle is driving on a good road, the one-way self-locking function of the worm gear ensures that the self-stabilizing cockpit system is not affected by road bumps and other conditions, and the self-stabilizing control does not work; when the vehicle is driving on a complex off-road road, the self-stabilizing The cockpit system determines that the vehicle state exceeds the preset threshold, and the self-stabilization control starts to work, and the stability control function of the self-stabilizing cockpit is realized through the worm gear. This innovative design solution can reduce the wear and tear of the mechanism in the self-stabilizing cockpit system, increasing the reliability and safety of the system.

Description of drawings

FIG. 1 is a three-dimensional schematic diagram of a self-stabilizing cockpit of an off-road special vehicle of the present invention.

Figure 2 is a schematic plan view of the self-stabilizing cockpit of an off-road special vehicle of the present invention; wherein Figure (a) is a partial enlarged view of Figure (b), Figure (b) is a top view, and Figure (c) is a front view.

FIG. 3 is a working principle diagram of the control system of the present invention.

FIG. 4 is a schematic diagram of the control threshold calculation principle of the control system of the present invention.

Description of reference numbers:

1-cockpit, 2-body, 3-cockpit carrier, 4-pitch motor controller, 5-first worm gear, 6-pitch control motor, 7-second worm gear, 8-side Tilt motor controller, 9-roll control motor.

Detailed ways

The present invention will be described in further detail below with reference to the accompanying drawings.

As shown in FIG. 1 , the self-stabilizing cockpit system of an off-road special vehicle of the present invention includes a cockpit 1 with rotational degrees of freedom in pitch and roll directions, a cockpit carrier 3 , motors 6 and 9 and motor controllers 4 and 8 . The pitch control motor 6 is connected with the cockpit 1 through the worm gear transmission mechanism 5 that can realize the self-locking function, the roll control motor 8 is connected with the cockpit carrier 3 through the worm gear and worm transmission mechanism 7, and the cockpit 1 is connected with the cockpit carrier 3 Bearings are used for connection between the cockpit carrier 3 and the body 2 .

Since the self-stabilizing cockpit system of the off-road special vehicle requires the cockpit 1 to be able to adjust its own posture in real time, the self-stabilizing cockpit 1 is designed as a symmetrical structure to avoid movement interference during the adjustment process. The cockpit 1 itself has a rotational degree of freedom in the pitch direction, and the cockpit carrier 3 provides the cockpit with a rotational degree of freedom in the roll direction.

The worm gear transmission mechanisms 5 and 7 have a self-locking function, the number of worm heads z ₁ =1, and the lead angle on the cylindrical worm satisfies γ≦3°30′. When the self-stable control motor is not working, the cockpit 1 and the cockpit carrier 3 and the cockpit carrier 3 and the body 2 are fixed by the one-way self-locking feature of the worm gear to prevent off-road special vehicles from driving on good roads. , due to acceleration, deceleration or steering, the posture of the cockpit 1 and the body 2 is out of sync, and self-rotation occurs, which affects the driving experience on a good road.

The working principle of self-stabilization control of this system is shown in Figure 2, which mainly includes three modules: control threshold calculation module, self-stabilization control module and executive motor module. Firstly, the tire force sensor of the off-road special vehicle provides the vertical force of the four tires for the control threshold calculation module of the self-stabilizing cockpit system of the off-road special vehicle. The control threshold calculation module calculates the control threshold Flag according to the vertical force analysis of the four tires. The control threshold Flag will be used as the working switch of the self-stable control module. When Flag=0, the self-stable control will not work, and the motors 6 and 9 will not exert force on the cockpit 1. When Flag=1, the self-stable control will work, and the motor 6 , 9 Real-time correction of cockpit 1 attitude. The self-stabilization control module takes the control threshold Flag and the dynamic parameters of the cockpit 1 as input, designs the control algorithm combined with the dynamic equation of the cockpit 1, and outputs the corrected torque T* of the attitude of the cockpit 1. Finally, the motor controllers 4 and 8 control the motors 6 and 9 to drive the worm gear transmission mechanisms 5 and 7 to correct the posture of the cockpit 1 in real time.

Specifically, the calculation and analysis method of the control threshold Flag in the control threshold calculation module of FIG. 2 is shown in FIG. 3 . Figure 3 takes the calculation of the roll attitude control threshold as an example, which is mainly divided into two parts, which are the calculation of the lateral load transfer ratio LTR (Lateral-load Transfer Ratio) value of the vehicle roll stability index and the analysis of the tire vertical force itself. judge. Vehicle Roll Stability Index The lateral load transfer rate LTR is a value that measures the critical point of rollover during vehicle motion. The calculation formula is:

In the formula, F _zr is the vertical load of the outer tire, and F _zl is the vertical load of the inner tire. The value range of LTR is [-1, 1]. When LTR=0, the wheel loads on the left and right sides are equal, and the vehicle will not roll over; when LTR=±1, the wheel load on one side of the vehicle is zero, and a rollover will occur. Therefore, it is possible to determine the rollover threshold LTR*=k·LTR _max , where k is the safety factor and LTR _max =±1. When LTR>LTR*, Flag1=1, otherwise Flag1=0.

However, the limit value ±1 of LTR can only represent the zero load on one side of the wheel, and cannot reflect the situation when two or more tires or non-identical tires have zero load. For example, when the load of all four tires is zero, the denominator of the LTR calculation formula is zero and cannot be calculated. Therefore, the control threshold calculation module also introduces a step of directly evaluating the four tire loads, which is combined with the LTR analysis to jointly determine the output of the control threshold module.

The tire load direct evaluation specifically refers to outputting Flag2=1 when only one of the four tires is 0, otherwise, outputting Flag2=0. Finally, the two evaluation indicators are combined: when Flag1+Flag2>0, Flag=1, otherwise Flag=0. That is, when only one of the two evaluation indexes mentioned above meets the control requirements, a work instruction is input to the self-stabilizing control module.

The pitch attitude control of the self-stabilizing cockpit system is similar to the roll attitude control method. The main difference is that the calculation method of the load transfer rate in the control threshold calculation module is different: the roll attitude control threshold calculation module adopts the lateral load transfer rate LTR ( Lateral-load Transfer Ratio); the pitch attitude control threshold calculation module adopts the longitudinal load transfer rate LTR (Longitudinal-load Transfer Ratio).

Claims (10)

1. A vehicle self-stabilizing cockpit is characterized by comprising a cockpit (1) with rotation freedom degrees in pitching and rolling directions and a cockpit carrier (3);

the cockpit (1) itself has a rotational degree of freedom in the pitch direction, and the cockpit carrier (3) provides the cockpit with a rotational degree of freedom in the roll direction.

2. The cab of claim 1, further comprising pitch control means for effecting control of the degree of freedom of rotation of the cab in a pitch direction and roll control means for effecting control of the degree of freedom of rotation of the cab in a roll direction.

3. The cockpit of claim 2, where the pitch control mechanism comprises a pitch motor controller (4), a first worm gear transmission (5) with self-locking function and a pitch control motor (6);

the pitching control motor (6) is connected with the cockpit (1) through a first worm gear transmission mechanism (5) capable of realizing a one-way self-locking function, and the pitching motor controller (4) is used for controlling the pitching control motor (6).

4. The cockpit of claim 3, characterized in that the roll control mechanism comprises a roll motor controller (8), a second worm gear transmission (7) with self-locking function and a roll control motor (9);

the side-tipping control motor (9) is connected with the cockpit bearing body (3) through a second worm gear transmission mechanism (7) capable of realizing a one-way self-locking function, and the side-tipping motor controller (8) is used for controlling the side-tipping control motor (9).

5. Cabin according to claim 4, wherein the number of heads of the worms of the first and second worm gear, z, is₁1 and the lead angle on the cylindrical worm meets the condition that gamma is less than or equal to 3 degrees and 30 degrees.

6. The cockpit according to claim 4, where bearings are used between the cockpit (1) and the cockpit carrier (3) and between the cockpit carrier (3) and the body (2).

7. The cabin according to claim 1, characterized in that the self-stabilizing cabin (1) is of a symmetrical construction, avoiding movement interferences during adjustment.

8. A control system for a cockpit according to any of claims 1-7 where force sensors are provided on the vehicle's tires and roll and pitch rate sensors are provided on the cockpit (1) to provide vehicle parameter inputs to the self-stabilizing control system;

the control system comprises a control threshold calculation module, a self-stabilization control module and an execution motor module;

the control threshold calculation module takes the vertical forces of the four tires as input quantity and obtains a control threshold Flag through analysis and calculation according to the vertical forces of the four tires;

the self-stabilization control module takes a control threshold Flag and the dynamic parameters of the cockpit (1) as input, designs a control algorithm by combining a dynamic equation of the cockpit (1), and outputs a correction torque T of the attitude of the cockpit (1);

the executing motor module comprises a pitching motor controller (4), a first worm gear transmission mechanism (5), a pitching control motor (6), a second worm gear transmission mechanism (7), a side-tipping motor controller (8) and a side-tipping control motor (9).

9. A method of self-stabilization control using the control system of claim 8, comprising the steps of:

step (1): the force sensors on the vehicle tires provide vertical forces of the four tires for the control threshold calculation module, and the control threshold calculation module obtains a control threshold Flag through analysis and calculation according to the vertical forces of the four tires;

step (2): the self-stabilization control module takes a control threshold Flag and the dynamic parameters of the cockpit (1) as input, designs a control algorithm by combining a dynamic equation of the cockpit (1), and outputs a correction torque T of the attitude of the cockpit (1);

and (3): and finally, the pitching motor controller (4) and the side-tipping motor controller (8) control the pitching control motor (6) and the side-tipping control motor (9) to drive the worm gear transmission mechanism to correct the attitude of the cockpit (1) in real time.

10. Method according to claim 9, characterized in that the self-stabilizing control module is not active when Flag is 0, the pitch control motor (6) and the roll control motor (9) do not generate forces on the cabin (1); when the Flag is equal to 1, the self-stabilization control module works, and the pitching control motor (6) and the rolling control motor (9) correct the posture of the cockpit (1) in real time.

Images