A wire-controlled angle drive module steering system

Abstract

The present invention belongs to the technical field of automobile chassis steering mechanism, and proposes a wire-controlled angle drive module steering system. The steering system includes a steering drive mechanism, a steering transmission mechanism, a steering arm, a suspension assembly and a wheel assembly connected in sequence; the steering transmission mechanism includes an angle actuator, a vehicle body connection flange, an RV reducer, an output flange, a nozzle and a wheel angle sensor. The wire-controlled angle drive module steering system can realize independent steering, improve vehicle dynamic response, and realize a variety of flexible driving modes; the RV reducer is used to realize steering torque increase and vertical load bearing, which can increase the chassis payload; as an independent module development, its design and development can be decoupled from the vehicle body, and a unified interface can be realized, plug and play, and quick disassembly and assembly with the vehicle body can be realized; feedback control is adopted, and the online optimization algorithm is used to suppress instantaneous and cumulative errors and maintain a high control accuracy.

Description

Technical Field

[0001] The invention belongs to the technical field of automobile chassis steering mechanisms, and in particular relates to a wire-controlled angle drive module steering system. Background Art

[0002] The intelligentization of automobiles can achieve safe, efficient and energy-saving driving, and has many huge advantages over traditional automobiles. Wire control technology is the technical foundation of intelligent automobiles. It eliminates the mechanical connection between driver input and actuator, and realizes sensing and control through data bus technology. Therefore, wire control steering technology has the advantages of fast steering response speed, accurate corner following, and flexible steering system layout. Independent steering technology eliminates the steering trapezoid of the traditional steering system, further enhances the dynamic performance of the vehicle, and can even realize a variety of flexible driving modes such as horizontal driving, oblique driving, on-the-spot steering, and four-wheel steering, which better serves the driving of intelligent automobiles. In summary, wire control independent steering is an important direction for the development of intelligent automobiles.

[0003] At present, most smart cars are based on traditional car chassis. Some smart car chassis use wire-controlled steering systems, which can achieve mechanical decoupling between driver input and actuator in general use, but still retain the mechanical steering structure for redundant backup, which cannot give full play to the advantages of flexible layout and small space occupied by wire-controlled steering systems. Some smart car chassis have achieved full mechanical decoupling wire-controlled steering, but do not support all-wheel independent steering. Its dynamic performance is similar to that of traditional chassis, and its driving mode is single; and the above-mentioned wire-controlled steering system has low integration with other chassis systems. The steering system, suspension system, and drive system are connected at different positions of the chassis respectively, and no unified interface that can be quickly disassembled and assembled is adopted. The degree of modularization and generalization is low, and disassembly and maintenance are inconvenient. With the development of smart car technology, its target objects have also expanded from general passenger cars to vehicles and chassis with larger curb weight and heavier load, such as 2-ton SUV chassis. The existing few wire-controlled independent steering configurations are only suitable for passenger cars or test vehicle platforms of 1 ton or less, and do not consider the need to withstand such loads. In addition, the existing wire-controlled steering system also has the problem of cumulative error as the use time increases. Its steering transmission mechanism will also reduce the steering control accuracy over time due to a series of problems such as idle travel and wear. After long-term use, it is necessary to introduce manual calibration. Therefore, the current wire-controlled steering system has the disadvantages of mechanical non-decoupling, poor dynamic performance, inflexible driving, low modularity, low load-bearing capacity, and reduced accuracy with use.

[0004] The Chinese invention patent application with publication number CN116238582A discloses an independent angle module, which includes an axle, a bogie, a vehicle body track, a steering drive unit and a leaf spring unit, wherein the axle is arranged and positioned on the wheel, the bogie is arranged on the axle and rotates integrally with the axle to apply a steering angle to the wheel, the vehicle body track is positioned on the vehicle body and arranged to the rotation center axis of the bogie, the steering drive unit is positioned between the bogie and the vehicle body track to apply a driving force, and the leaf spring unit is positioned between the axle and the bogie, wherein the steering drive unit rotates along the vehicle body track in response to the driving force of the steering drive unit, and the bogie is configured to rotate around the steering drive unit. The invention adopts a transmission mode of gears and arc-shaped racks to realize wheel steering, which can provide a larger wheel turning angle and can reduce the impact on the wheel in the longitudinal and vertical directions of the vehicle. However, the invention cannot achieve a ±90° turning angle range, has poor driving flexibility, and the longitudinal and vertical impacts directly act on the steering transmission pair, which has an adverse effect on the steering characteristics.

[0005] A Chinese utility model patent with announcement number CN217864336U discloses an angle module structure and a vehicle, the angle module structure includes a wheel, a steering assembly and a suspension assembly, the steering assembly is connected to the wheel, the rotation centerline of the steering assembly relative to the wheel is L1, the steering assembly can drive the wheel to rotate with L1 as the centerline, thereby realizing the functions of lateral driving, oblique driving and on-the-spot steering of the vehicle, the suspension assembly includes a bracket, a first connecting arm and a second connecting arm, the bracket is installed on the steering assembly, the first connecting arm and the second connecting arm are both used to connect to the vehicle body, the first connecting arm and the second connecting arm are equal in length and parallel to each other to form a parallelogram linkage mechanism, so that the rotation centerline L1 is coaxial with the plumb line of the wheel during the up and down jumping of the wheel, that is, the rotation centerline L1 is always perpendicular to the ground through the plumb line of the wheel, thereby ensuring that the grounding point of the wheel remains unchanged, and the steering resistance torque remains unchanged when the load remains unchanged. The upper and lower control arms and shock absorbers of the utility model patent suspension need to be connected to the vehicle body separately, with many interfaces, complex disassembly and assembly, and a low degree of modularity; the steering system has a simple structure, and the ability of the rotating structure to carry vertical loads is poor, which is not suitable for the expansion of larger platforms in the future.

[0006] The Chinese invention patent application with the publication number CN115489586A discloses a wheel module for a vehicle and the vehicle itself. The wheel module includes: a rocker arm, which is used to be swingably mounted on the vehicle frame and has a first rocker arm end and a second rocker arm end; a steering member, which is used to connect the wheel and has a first steering member end and a second steering member end; a steering drive member, which is used to drive the steering member to rotate; a transmission device, which includes two aligning rotating connection components arranged with their respective center points coinciding, namely, a first aligning rotating connection component coupling the first rocker arm end and the first steering member end, and a second aligning rotating connection component coupling the first steering member end and the steering drive component; and a multi-directional rotating connection component, which connects the second steering member end and the second rocker arm end. The vehicle includes the above-mentioned wheel module. The invention can achieve a ±90° turning angle range, has good driving flexibility, and the steering drive component directly drives the slewing structure and the wheel to turn after deceleration, and has good steering characteristics and wheel alignment parameters. However, the upper end of the shock absorber and the steering drive component need to be connected to the frame and the body respectively, with many interfaces, complicated disassembly and assembly, and a low degree of modularization. Summary of the invention

[0007] In view of the above-mentioned deficiencies in the prior art, the present invention proposes a wire-controlled angle drive module steering system, which has the characteristics of flexible layout, good performance and fast assembly and disassembly, and can realize wire-controlled steering and independent steering functions.

[0008] The technical solution of the present invention is as follows:

[0009] A wire-controlled angle drive module steering system comprises a steering drive mechanism, a steering transmission mechanism, a steering arm, a suspension assembly and a wheel assembly connected in sequence;

[0010] The steering transmission mechanism includes an angle actuator, a body connection flange, an RV reducer, an output flange, a nozzle and a wheel angle sensor;

[0011] The steering arm includes a side extension portion and a vertical portion. The middle portion of the side extension portion is protruded and consists of a first inclined plate and a second inclined plate. The shock absorber of the suspension assembly is fixed on the first inclined plate, and the second inclined plate is connected to the steering transmission mechanism. The vertical portion is connected to the upper and lower swing arms of the suspension assembly.

[0012] Preferably, the angle actuator is installed on the upper surface of the vehicle body connecting flange, the upper end of the RV reducer is connected to the lower surface of the vehicle body connecting flange, the upper surface of the output flange is connected to the lower end of the RV reducer and serves to seal the RV reducer housing, the vehicle body connecting flange is detachably connected to the vehicle body, and the wheel angle sensor is connected to the steering arm.

[0013] Preferably, the oil nozzle is arranged on the vehicle body connecting flange and the output flange; the vehicle body connecting flange is fixed to the vehicle body and does not rotate with the steering arm; and a through hole for the wiring harness to pass through is arranged on the vehicle body connecting flange.

[0014] Preferably, the rotation axis of the output flange is coaxial with the central axis of the RV reducer.

[0015] Preferably, the angular transmission comprises a coupling, an input shaft, an input bevel gear, an output bevel gear and an output shaft connected in sequence.

[0016] Preferably, the angle transmission and the body connecting flange, the RV reducer and the body connecting flange, the RV reducer and the output flange, and the body connecting flange and the body are all connected by bolts.

[0017] Preferably, the steering drive mechanism is a servo motor, the output axis of the servo motor is parallel to the ground and is installed on the angle actuator.

[0018] Preferably, the upper end of the steering arm is connected to the lower surface of the output flange, and the rotation axis of the steering arm is coaxial with the central axis of the RV reducer.

[0019] Preferably, the suspension assembly is connected to the steering arm by a combination of bolt fixing and hinge connection.

[0020] Preferably, the wheel assembly is connected to the suspension assembly via bolts.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. The wire-controlled angle drive module steering system proposed in the present invention is designed to achieve a large turning angle range of ±90° and above, and can realize independent steering to improve the dynamic response of the vehicle. At the same time, it can realize multiple flexible driving modes such as lateral driving, oblique driving, on-the-spot steering, and four-wheel steering.

[0023] 2. The wire-controlled angle drive module steering system proposed in the present invention adopts a large-ratio RV reducer to achieve steering torque increase, which can overcome the significant increase in steering resistance torque caused by a heavy-loaded chassis. The RV reducer has a built-in bearing group, which has a stronger vertical load-bearing capacity than a general reducer, and can increase the chassis payload, achieving adaptation to wheel chassis of 2 tons and above.

[0024] 3. The wire-controlled angle drive module steering system proposed in the present invention is developed as an independent module. Its design and development can be decoupled from the vehicle body and can be adapted to a variety of chassis of different sizes. Compared with other angle module products, a vehicle body connection flange is specially provided and fixedly connected to the vehicle body, so that a unified interface for connecting to the vehicle body can be achieved, which is plug-and-play and can be quickly disassembled and assembled with the vehicle body.

[0025] 4. The wire-controlled angle drive module steering system proposed in the present invention adopts a feedback control method, which can be combined with an optimization algorithm to automatically suppress instantaneous errors and cumulative errors, and can maintain a high control accuracy for a long time. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. The features and advantages of the present invention can be more clearly understood by referring to the drawings. The drawings are schematic and should not be understood as limiting the present invention in any way. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0027] Figure 1 Schematic diagram of the structure of the steering system of the wire control angle drive module in the embodiment.

[0028] Figure 2 is a front view of the wire-controlled angle drive module steering system in the embodiment.

[0029] Figure 3 Schematic diagram of the connection between the steering transmission mechanism and the steering arm in the embodiment.

[0030] Figure 4 Schematic diagram of the structure of the angle actuator in the embodiment.

[0031] Figure 5 is a control flow chart of the steering system of the wire control angle drive module in the embodiment.

[0032] Among them, 1-steering drive mechanism, 2-steering transmission mechanism, 3-steering arm, 4-suspension assembly, 5-wheel assembly, 21-angle transmission, 22-body connecting flange, 23-RV reducer, 24-output flange, 25-oil nozzle, 26-wheel angle sensor, 201-bolt, 202-bolt, 203-bolt, 204-bolt, 211-coupling, 212-input shaft, 213-input bevel gear, 214-output bevel gear, 215-output shaft. DETAILED DESCRIPTION

[0033] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0034] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0035] The wire-controlled angle drive module steering system provided in this embodiment is composed of a steering drive mechanism 1, a steering transmission mechanism 2, a steering arm 3, a suspension assembly 4 and a wheel assembly 5.

[0036] like Figure 1 , Figure 2 As shown, the steering transmission mechanism 2 includes an angle transmission device 21, a body connection flange 22, an RV reducer 23, an output flange 24, a nozzle 25, and a wheel angle sensor 26; the angle transmission device 21 is installed on the body connection flange 22 and connected to the upper surface of the body connection flange 22.

[0037] like Figure 3 As shown, the RV reducer 23 is not provided with an output shaft, and directly uses the output flange 24 for output, which can effectively improve the torque transmitted by the reducer compared with the shaft output reducer; the upper end of the RV reducer 23 is connected to the lower surface of the body connection flange 22 by 16 evenly distributed bolts 201; the output flange 24 is connected to the lower end of the RV reducer 23 by 18 bolts 202 and 6 bolts 203, outputs the torque amplified by the RV reducer 23, and seals the lower end of the RV reducer 23 from the outside to form a complete shell, and the rotation axis L2 of the output flange 24 is coaxial with the central axis of the RV reducer 23; the oil nozzle 25 is respectively installed on the body connection flange 22 and the output flange 24; the wheel angle sensor 26 is installed on the steering arm 3 by bolt connection or welding.

[0038] The body connection flange 22 has 6 through holes, is fixedly connected to the body by bolts, and does not rotate with the steering arm 3, so as to achieve a unified interface and quick disassembly and assembly with the body. The body connection flange 22 is provided with a plurality of through holes to reduce weight, and the wiring harness can pass through the through holes to connect to the body.

[0039] The steering drive mechanism 1 includes a servo motor, which is connected to a servo driver on the vehicle body through high and low voltage wire harnesses, thereby realizing wire-controlled steering.

[0040] The output axis L1 of the servo motor is parallel to the ground and is mounted on the angle actuator 21. Figure 4 As shown, the angular transmission 21 is connected to the servo motor output shaft through a coupling 211, which drives the angular transmission input shaft 212, the input bevel gear 213 and the output bevel gear 214 to rotate in turn, and finally transmits the torque to the RV reducer 23 through the output shaft 215 of the angular transmission 21, thereby realizing the torque transmission from L1 to L2.

[0041] like Figure 3 As shown, the upper end of the steering arm 3 is connected to the output flange 24 through 9 bolts 204; the rotation axis L3 of the steering arm 3 is coaxial with the central axis of the RV reducer 23.

[0042] like Figure 2 As shown, the steering arm 3 includes a side extension part and a vertical part. The middle part of the side extension part is bulged, and is composed of a first inclined plate and a second inclined plate. The angle between the first inclined plate and the second inclined plate and the horizontal plane is 15-20°. The shock absorber of the suspension assembly 4 is fixed on the first inclined plate, and the second inclined plate is connected to the steering transmission mechanism 2. The vertical part is connected to the upper and lower swing arms of the suspension assembly. The side extension part of this embodiment can effectively utilize the space under the vehicle body connection flange 22, increase the total length of the shock absorber under the condition that the length of the vertical part remains unchanged, increase the wheel bounce range, and facilitate off-road driving of the vehicle. The vertical part is a single-layer plate structure, and holes are opened on the full height from top to bottom to reduce weight and set wiring harness fixing holes. The wiring harnesses of the suspension assembly 4 and the wheel assembly 5 can be passed through the wiring harness fixing holes and fixed, which is conducive to the lightweight and wiring harness arrangement of the steering system of the wire-controlled angle drive module.

[0043] The suspension assembly 4 is installed on the steering arm 3 by a combination of bolt fixing and hinge connection.

[0044] The wheel assembly 5 is mounted on the suspension assembly 4 by bolt connection.

[0045] When the wire-controlled angle drive module steering system is installed on the chassis of an intelligent vehicle, the ground reaction force supports the vertical load applied by the vehicle body through the wheel assembly 5, the suspension assembly 4, the steering arm 3, the output flange 24, the RV reducer 23 and the vehicle body connection flange 22. Since the deceleration ratio of the RV reducer 23 is relatively large, it can effectively reduce speed and increase torque, providing a larger steering torque to overcome the large steering resistance torque of the heavy-loaded chassis; and the RV reducer 23 has multiple pairs of bearings inside, and its ability to withstand axial loads is much greater than that of general reducers. Therefore, the wire-controlled angle drive module steering system using the RV reducer 23 can increase the chassis payload, and after testing, it can be adapted to the wheel chassis of 2 tons and above.

[0046] During the steering process, the servo motor transmits the steering torque to the steering arm 3 through the angle transmission 21 and the RV reducer 23 and the output flange 24. The steering arm 3 transmits the steering torque to the wheel assembly 5 through the suspension assembly 4, which is actually manifested as the steering arm 3 driving the suspension assembly 4 and the wheel assembly 5 to rotate as a whole, thereby realizing the independent steering of one wheel controlled by one steering motor.

[0047] like Figure 5As shown, the steering system of the wire control angle drive module can support two different command input modes of manned driving and automatic driving according to the different vehicle platforms it is equipped with. The driver sends an operation signal to the vehicle through the steering wheel or operation button or operation panel, which is converted into a steering command, or the autopilot sends a steering command to the vehicle by following the planned driving path. Thereafter, the steering command is input into the electronic control unit (ECU) of the vehicle, and through calculation and processing, a steering control signal is sent to the servo driver installed on the vehicle body. The servo driver controls the servo motor according to the control signal, so that the wheel turns to the target position, realizes the angle following, and completes the operation target of the driver or the autopilot. The steering drive mechanism 1 and the wheel angle sensor 26 can feed back signals such as wheel angle, steering speed, and steering resistance torque to the ECU. The ECU can optimize the control parameters of the steering motor controller online according to the error information through an online optimization algorithm, thereby eliminating the instantaneous error and cumulative error of the steering system of the wire control angle drive module in real time during driving, further improving its control accuracy, and avoiding the need to frequently recalibrate and calibrate the system manually.

[0048] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0049] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0050] In the present invention, the terms "first", "second", "third", "fourth" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance. The term "plurality" refers to two or more, unless otherwise clearly defined.

[0051] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A wire-controlled angle drive module steering system, characterized in that: It includes a steering drive mechanism, a steering transmission mechanism, a steering arm, a suspension assembly and a wheel assembly connected in sequence; The steering transmission mechanism includes an angle actuator, a body connection flange, an RV reducer, an output flange, a nozzle and a wheel angle sensor; The steering arm comprises a side extension part and a vertical part, the middle part of the side extension part is convex, and is composed of a first inclined plate and a second inclined plate, the first inclined plate is fixed with the shock absorber of the suspension assembly, the second inclined plate is connected with the steering transmission mechanism, and the vertical part is connected with the upper and lower swing arms of the suspension assembly; The angle actuator is mounted on the upper surface of the vehicle body connection flange, the upper end of the RV reducer is connected to the lower surface of the vehicle body connection flange, the upper surface of the output flange is connected to the lower end of the RV reducer and serves as a seal for the RV reducer housing, the vehicle body connection flange is detachably connected to the vehicle body, and the wheel angle sensor is connected to the steering arm; The angle transmission and the body connection flange, the RV reducer and the body connection flange, the RV reducer and the output flange, and the body connection flange and the body are all connected by bolts; The angular transmission comprises a coupling, an input shaft, an input bevel gear, an output bevel gear and an output shaft which are connected in sequence.

2. The steering-by-wire angle drive module system according to claim 1, characterized in that: The oil nozzle is arranged on the vehicle body connecting flange and the output flange; the vehicle body connecting flange is fixed to the vehicle body and does not rotate with the steering arm; and a through hole for the wiring harness to pass through is arranged on the vehicle body connecting flange.

3. The steering-by-wire angle drive module system according to claim 1, characterized in that: The rotation axis of the output flange is coaxial with the central axis of the RV reducer.

4. The steering-by-wire angle drive module system according to claim 1, characterized in that: The steering drive mechanism is a servo motor, the output axis of the servo motor is parallel to the ground and is installed on the angle transmission.

5. The steering-by-wire angle drive module system according to claim 1, characterized in that: The upper end of the steering arm is connected to the lower surface of the output flange, and the rotation axis of the steering arm is coaxial with the central axis of the RV reducer.

6. The steering-by-wire angle drive module system according to claim 1, characterized in that: The suspension assembly is connected to the steering arm by a combination of bolt fixing and hinge connection.

7. The steering-by-wire angle drive module system according to claim 1, characterized in that: The wheel assembly is connected to the suspension assembly via bolts.

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