WO2022111553A1

WO2022111553A1 - Unmanned four-wheel independent steering chassis platform steering system for low-speed vehicle

Info

Publication number: WO2022111553A1
Application number: PCT/CN2021/132975
Authority: WO
Inventors: 徐亦航; 向东峰
Original assignee: 上海龙创汽车设计股份有限公司
Priority date: 2020-11-29
Filing date: 2021-11-25
Publication date: 2022-06-02
Also published as: DE112021004703T5; CN112373556A

Abstract

An unmanned four-wheel independent steering chassis platform steering system for a low-speed vehicle, relating to the technical field of autonomous driving. The system comprises a vehicle body framework (1) and four sets of independent steering systems provided at the bottom of the vehicle body frameworks (1); each set of independent steering systems comprise a steering system (3), a driving system (4), and a suspension system (2); the steering system (3) is mounted between the driving system (4) and the suspension system (2); each set of steering systems (3) comprise a housing (14), a steering motor (5), a worm gear (10), a steering knuckle (16), and a worm (7); the worm (7) is engaged with the worm gear (10); the main shaft of the steering motor (5) is connected to the worm (7) by means of a coupling (6); the moving end of the steering knuckle (16) is fixedly connected to the driving system (4); by means of the steering system (3), the high-precision control of the driving system (4) can be achieved, and the driving system (4) can freely rotate by 360 degrees; a large worm bearing (8) and a small worm bearing (13) both are self-aligning bearings; and after the worm gear (10) and the worm (7) are worn for a long time, clearance compensation can be performed by means of the self-aligning bearings, thereby achieving the adjustment of the axis of the worm (7).

Description

A low-speed vehicle unmanned four-wheel independent steering chassis platform steering system

technical field

The invention relates to the technical field of unmanned driving, in particular to a low-speed vehicle unmanned four-wheel independent steering chassis platform steering system.

Background technique

With the rapid development and maturity of driverless technology, there are more and more researches on the technical solutions of driverless chassis system by wire. There are limited applications for driverless vehicles.

The unmanned vehicle in the prior art cannot realize the 360-degree steering of the wheels at any angle, and thus cannot guarantee the vehicle's in-situ steering and steering at any angle. corner, so the driving accuracy of the vehicle cannot be guaranteed.

The above two

reference documents

1 and 2 both disclose the technical problem to be solved by the present application, which is that clearance compensation can be performed by self-aligning bearings, and other reference documents also record the self-locking function of the turbine worm.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a low-speed vehicle unmanned four-wheel independent steering chassis platform steering system to solve the technical problems in the prior art that the vehicle cannot be guaranteed to be steered at any angle and that the vehicle is prone to turning angle after being hit by the road surface.

The technical scheme of the present invention is: comprising a body frame and four sets of independent steering systems arranged at the bottom of the body frame, wherein: each set of independent steering systems includes a steering system, a driving system and a suspension system, and the suspension system is fixed on the body On the skeleton, the steering system is installed between the driving system and the suspension system, and the steering system is used to drive the driving system to perform steering;

Each group of the steering systems includes a casing, a steering motor, a turbine and a worm, the turbine and the turbine shaft are connected by interference fit, the worm and the turbine shaft are perpendicular to each other, and both the worm and the turbine shaft are rotatable. In the housing, the steering motor is mounted on the side wall of the housing in a fixed connection manner, the worm is engaged with the worm gear, and the main shaft of the steering motor and the worm are connected by a coupling.

Each group of the steering systems further includes a steering knuckle, the movable end of the steering knuckle is fixedly connected with the driving system, and the bottom end of the worm gear shaft is fixedly connected with the top end of the steering knuckle

Further, both sides of the housing are respectively fitted with a large worm bearing and a small worm bearing, and two ends of the worm are respectively fitted with a large worm bearing and a small worm bearing.

Further, the upper and lower ends of the casing are respectively fitted with an upper worm wheel bearing and a lower worm wheel bearing, and two ends of the worm shaft are respectively fitted with an upper worm wheel bearing and a lower worm wheel bearing.

Further, the large worm bearing and the small worm bearing are self-aligning bearings.

Further, the casing is provided with a worm plug cover which is in an interference fit therewith.

Further, the steering motor is a servo motor, a stepping motor, a brushless motor or a brushed motor.

Further, the suspension system includes a spline slide column, a spline slide sleeve, an elastic member, a lower limit buffer block, a lower limit pad and an upper cover fixed on the top of the housing, the upper cover and the spline slide The column is connected by welding, the elastic piece is sleeved on the spline sliding column, the two ends of the elastic piece are respectively connected to the top of the upper cover and the bottom of the body frame, and the lower limit buffer block and the lower limit pad are connected by vulcanization The spline sliding sleeve is coaxially sleeved on the spline sliding column, and the spline sliding sleeve is fixed on the body frame.

Further, the elastic member is a heat-resistant rubber tube or a spring.

The present invention provides a low-speed vehicle unmanned four-wheel independent steering chassis platform steering system through improvement, which has the following improvements and advantages compared with the prior art:

First, the present invention can realize high-precision control of the driving system through the steering system, and can make the driving system rotate freely in 360 degrees. Rotation, the turbine drives the turbine shaft to rotate, and then the turbine shaft drives the universal joint to rotate, so as to realize the rotation of the driving system along the axis of the turbine shaft; by controlling the worm gear and the worm drive to cooperate, under the self-locking function of the worm gear and worm, To improve the rudder protection ability of the vehicle, so as to improve the driving accuracy of the vehicle;

By controlling the cooperation of the worm gear and the worm drive, under the self-locking function of the worm gear and the worm, the rudder protection ability of the vehicle is improved, so as to improve the driving accuracy of the vehicle and avoid the situation that the vehicle is prone to turning angles after being hit by the road surface, so as to solve the problem of the prior art. There is no guarantee that the vehicle can be turned at any angle and the technical problems that the vehicle is prone to turning after being hit by the road surface cannot be avoided.

Second, in order to realize the adjustment of the worm shaft, the large worm bearing and the small worm bearing are self-aligning bearings. When the worm gear and worm wear out for a long time, the clearance compensation can be performed by the self-aligning bearing to realize the adjustment of the worm shaft. This further improves the running accuracy after the vehicle durability test.

Third, when the steering motor drives the worm to rotate, the housing will vibrate due to the operation of the steering motor, which will cause the movement of the driving system and affect the accuracy of the driving system. The key sliding sleeve is fixed on the body frame. When the worm drives the worm gear meshing with it to rotate or when driving on a bumpy path, the upper cover will not be greatly offset under the limit of the spline sliding column, thereby further ensuring the vehicle The driving accuracy is excellent; the use of elastic parts can prevent the vehicle from shaking when driving on a bumpy path.

Description of drawings

Below in conjunction with accompanying drawing and embodiment, the present invention is further explained:

1 is a schematic side view of the present invention;

Fig. 2 is the three-dimensional structure schematic diagram of steering system;

Figure 3 is an exploded view of the steering system;

Figure 4 is a partial cross-sectional view one of the steering system;

Figure 5 is a partial cross-sectional view two of the steering system;

Figure 6 is an exploded view of the suspension system.

Description of reference numbers:

1. Body frame; 2. Suspension system; 21. Spline sliding column; 22. Spline sliding sleeve; 23. Lower limit buffer block; 24. Lower limit pad; 25. Upper cover; 26. Elastic part; 3 , steering system; 4, driving system; 5, steering motor; 6, coupling; 7, worm; 8, large worm bearing; 9, upper bearing of worm wheel; 10, worm wheel; 11, worm wheel shaft; 12, worm plug ; 13. Small worm bearing; 14. Housing; 15. Worm gear lower bearing; 16. Steering knuckle.

Detailed ways

The present invention will be described in detail below with reference to Fig. 1 to Fig. 5, and the technical solutions in the embodiments of the present invention will be described clearly and completely. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the implementations. example. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

The present invention provides an unmanned four-wheel independent steering chassis platform steering system for a low-speed vehicle through improvement. As shown in FIGS. 1-5 , the present invention includes a body frame 1 and four sets of independent steering systems arranged at the bottom of the body frame 1, wherein : Each group of independent steering systems includes a steering system 3, a driving system 4 and a suspension system 2, the suspension system 2 is fixed on the body frame 1, and the steering system 3 is installed between the driving system 4 and the suspension system 2 During the time, the steering system 3 is used to drive the driving system 4 to steer;

Each group of the steering systems 3 includes a housing 14 , a steering motor 5 , a worm gear 10 , a steering knuckle 16 and a worm 7 . The worm gear 10 and the worm shaft 11 are connected by interference fit, and the worm 7 and the worm shaft 11 are connected to each other. Vertically, the worm 7 and the worm gear shaft 11 are rotatably arranged in the housing 14, the steering motor 5 is mounted on the side wall of the housing 14 in a fixed connection, and the worm 7 is engaged with the worm gear 10, The main shaft of the steering motor 5 and the worm 7 are connected through the coupling 6 , the movable end of the steering knuckle 16 is fixedly connected with the driving system 4 , and the bottom end of the worm gear shaft 11 is fixedly connected with the top of the steering knuckle 16 . Through the steering system 3, the high-precision control of the driving system 4 can be realized, and the driving system 4 can be freely rotated 360 degrees. Specifically, the worm 7 is driven to rotate by the steering motor 5, and the worm 7 is driven to engage with it. The worm gear 10 rotates, so that the worm gear 10 drives the worm gear shaft 11 to rotate, and then the worm gear shaft 11 drives the steering knuckle 16 to rotate, so as to realize the rotation of the driving system 4 along the axis of the worm gear shaft 11; In cooperation, under the self-locking function of the worm gear 10 and the worm 7, the rudder-maintaining ability of the vehicle is improved, thereby improving the running accuracy of the vehicle.

Each group of the steering systems 3 further includes a steering knuckle 16 , the movable end of the steering knuckle 16 is fixedly connected to the driving system 4 , the bottom end of the worm gear shaft 11 is fixedly connected to the top end of the steering knuckle 16 ; During the rotation process, the steering knuckle 16 can be driven to rotate, so as to realize the rotation of the traveling system 4 along the axis of the worm gear shaft 11 .

Specifically, two sides of the housing 14 are respectively fitted with a large worm bearing 8 and a small worm bearing 13, and two ends of the worm 7 are respectively fitted with a large worm bearing 8 and a small worm bearing 13; The bearing 8 and the small worm bearing 13 are used to install the worm 7, so that the worm 7 can rotate along its axis, reduce the friction coefficient caused by the rotation of the worm 7, and ensure the rotation accuracy of the worm 7.

Specifically, the upper and lower ends of the housing 14 are respectively fitted with an upper worm wheel bearing 9 and a lower worm wheel bearing 15 , and both ends of the worm wheel shaft 11 are respectively fitted with an upper worm wheel bearing 9 and a lower worm wheel bearing 15 by interference fit; The worm wheel upper bearing 9 and the worm wheel lower bearing 15 are used to install the worm wheel shaft 11 , reduce the friction coefficient caused by the rotation of the worm wheel shaft 11 , and ensure the rotation accuracy of the worm wheel shaft 11 .

In order to realize the adjustment of the axis of the worm 7, specifically, the large worm bearing 8 and the small worm bearing 13 are self-aligning bearings; the large worm bearing 8 and the small worm bearing 13 are self-aligning bearings, when the worm wheel 10 worm 7 After durable wear, the self-aligning bearing can be used for clearance compensation to adjust the axis of the worm 7, thereby improving the driving accuracy of the vehicle after the durability test.

Specifically, the housing 14 is provided with a worm plug cover 12 that is in an interference fit therewith.

Specifically, the steering motor 5 is a servo motor, a stepping motor, a brushless motor or a brushed motor.

Specifically, in order to prevent the housing 14 from shifting with the operation of the steering motor 5 , the suspension system 2 includes a spline slide 21 , a spline slide sleeve 22 , a lower limit buffer block 23 , and a lower limit pad 24 and the upper cover 25 fixed on the top of the housing 14, the upper cover 25 is connected with the spline slide 21 by welding, the elastic piece 26 is sleeved on the spline slide 21, and the two ends of the elastic piece 26 respectively connected to the top of the upper cover 25 and the bottom of the body frame 1, the lower limit buffer block 23 and the lower limit pad 24 are connected by vulcanization, the spline sliding sleeve 22 is coaxially sleeved on the spline sliding column 21, and The spline sliding sleeve 22 is fixed on the body frame 1; when the steering motor 5 drives the worm 7 to rotate, the housing 14 shakes due to the operation of the steering motor 5, which in turn causes the movement of the driving system 4, which affects the accuracy of the driving system 4 As shown in FIG. 6 , the spline sliding sleeve 22 is set on the spline sliding column 21, and the spline sliding sleeve 22 is fixed on the body frame 1. When the worm 7 drives the worm wheel 10 meshing with it to rotate or in a bumpy When driving on the road, the upper cover 25 will not be greatly offset under the limit of the spline spool 21, thereby further ensuring the driving accuracy of the vehicle; the use of the elastic member 26 can prevent the vehicle from running on a bumpy road. jitter.

The elastic member 26 is a heat-resistant rubber tube or spring, and the heat-resistant rubber tube or spring can use its own deformation to play a certain buffering effect on the body frame 1 .

The working principle of the present invention: the steering system 3 can achieve high-precision control of the driving system 4, and the driving system 4 can be freely rotated 360 degrees. Specifically, the steering motor 5 works to drive the worm 7 to rotate, so that the The worm 7 drives the worm wheel 10 meshed with it to rotate, so that the worm wheel 10 drives the worm wheel shaft 11 to rotate, and then the worm wheel shaft 11 drives the steering knuckle 16 to rotate, so as to realize the rotation of the driving system 4 along the axis of the worm wheel shaft 11; by controlling the worm wheel 10 cooperates with the worm 7 in transmission, under the self-locking function of the worm wheel 10 and the worm 7, to improve the rudder protection ability of the vehicle, thereby improving the driving accuracy of the vehicle;

In order to realize the adjustment of the shaft center of the worm 7, the large worm bearing 8 and the small worm bearing 13 are self-aligning bearings. When the worm wheel 10 and the worm 7 wear out for a long time, clearance compensation can be performed by the self-aligning bearing to realize the adjustment of the shaft center of the worm 7. adjustment, thereby improving the driving accuracy of the vehicle after the durability test.

The above description of the disclosed embodiments enables any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

A low-speed vehicle unmanned four-wheel independent steering chassis platform steering system, comprising a body frame (1) and four sets of independent steering systems arranged at the bottom of the body frame (1), characterized in that each set of independent steering systems includes a steering system (3), a driving system (4) and a suspension system (2), the suspension system (2) is fixed on the body frame (1), the steering system (3) is installed on the driving system (4) and the suspension system (2) Between the frame systems (2), the steering system (3) is used to drive the driving system (4) for steering;

Each set of the steering systems (3) includes a housing (14), a steering motor (5), a worm gear (10) and a worm (7), the worm gear (10) and the worm gear shaft (11) are connected by interference fit , the worm (7) and the worm gear shaft (11) are perpendicular to each other, the worm (7) and the worm gear shaft (11) are both rotatably arranged in the housing (14), and the steering motor (5) is fixed to The connection is installed on the side wall of the housing (14), the worm (7) is engaged with the worm wheel (10), and the main shaft of the steering motor (5) and the worm (7) pass through the coupling (6). )connect.
The unmanned four-wheel independent steering chassis platform steering system for low-speed vehicles according to claim 1, wherein each group of the steering systems (3) further comprises a steering knuckle (16), and the steering knuckle (16) has a The movable end is fixedly connected with the traveling system (4), and the bottom end of the worm gear shaft (11) is fixedly connected with the top end of the steering knuckle (16).
The unmanned four-wheel independent steering chassis platform steering system for low-speed vehicles according to claim 1, characterized in that: both sides of the housing (14) are respectively fitted with a large worm bearing (8) and a small worm bearing ( 13), the two ends of the worm (7) are respectively in interference fit with the large worm bearing (8) and the small worm bearing (13).
The unmanned four-wheel independent steering chassis platform steering system for low-speed vehicles according to claim 1, wherein the upper and lower ends of the casing (14) are respectively fitted with an upper worm wheel bearing (9) and a lower worm wheel bearing. (15), the two ends of the worm gear shaft (11) are respectively in interference fit with the worm gear upper bearing (9) and the worm gear lower bearing (15).
The unmanned four-wheel independent steering chassis platform steering system for low-speed vehicles according to claim 3, wherein the large worm bearing (8) and the small worm bearing (13) are self-aligning bearings.
The unmanned four-wheel independent steering chassis platform steering system for low-speed vehicles according to claim 1, characterized in that: the casing (14) is provided with a worm plug cover (12) that is in an interference fit therewith.
The unmanned four-wheel independent steering chassis platform steering system for low-speed vehicles according to claim 1, wherein the steering motor (5) is a servo motor, a stepping motor, a brushless motor or a brushed motor.
The unmanned four-wheel independent steering chassis platform steering system for low-speed vehicles according to claim 5, wherein the suspension system (2) comprises a spline spool (21), an elastic member (26), a spline The sliding sleeve (22), the lower limit buffer block (23), the lower limit pad (24) and the upper cover (25) fixed on the top of the casing (3), the elastic member (26) is sleeved on the spline slide On the column (21), the two ends of the elastic member (26) are respectively connected to the top of the upper cover (25) and the bottom of the body frame (1), and the upper cover (25) is connected to the spline slide (21) By welding connection, the lower limit buffer block (23) and the lower limit pad (24) are connected by vulcanization, the spline sliding sleeve (22) is coaxially sleeved on the spline sliding column (21), and the spline sliding sleeve (21) is (22) is fixed on the body frame (1).
The unmanned four-wheel independent steering chassis platform steering system for low-speed vehicles according to claim 8, wherein the elastic member (26) is a heat-resistant rubber tube or a spring.