CN-121997495-A - Paddy field light chassis variable steering damping physical simulation system and method based on steering tie rod projection

CN121997495ACN 121997495 ACN121997495 ACN 121997495ACN-121997495-A

Abstract

The invention relates to the technical field of agricultural equipment, in particular to a paddy field light chassis variable steering damping physical simulation system and method based on steering tie rod projection, wherein the system comprises an input acquisition module, a steering control module and a control module, wherein the input acquisition module is used for acquiring a steering command signal input from the outside; the physical simulation module comprises a physical steering link mechanism used for reproducing mechanical movement of the physical steering system, a variable load simulation device connected with the physical steering link mechanism and used for applying a simulation load according to a steering command signal so as to reproduce external resistance applied to the steering system under a preset working condition, a state sensing module used for measuring movement state parameters of the physical steering link mechanism in real time, and a processing control module comprising a built-in kinematic model which is built by a dimension-reduction projection method based on three-dimensional geometric parameters and used for representing a mapping relation between movement of the physical steering link mechanism in a three-dimensional space and two-dimensional plane projection.

Inventors

JIA WEIQING
GUO ZIYOU
WANG ZAIMAN
ZHANG MINGHUA
FAN ZUNCHENG
XU YIMING
XU SHENJIE
Li Zhengrou

Assignees

华南农业大学

Dates

Publication Date: 20260508
Application Date: 20260128

Claims (10)

1. A paddy field light chassis becomes damping physical simulation system that turns to based on tie rod projection, its characterized in that includes: The input acquisition module is used for acquiring an externally input steering instruction signal; a physical simulation module, comprising: the physical steering link mechanism is used for reproducing the mechanical movement of the physical steering system; The variable load simulation device is connected with the physical steering link mechanism and is used for applying a simulation load according to a steering command signal so as to reproduce external resistance of the steering system under a preset working condition; The state sensing module is used for measuring the motion state parameters of the physical steering link mechanism in real time; A process control module, comprising: The built-in kinematic model is built on the basis of three-dimensional geometric parameters through a dimension reduction projection method and used for representing the mapping relation between the motion of the physical steering link mechanism in a three-dimensional space and the projection of a two-dimensional plane.
2. The paddy field light chassis variable steering damping physical simulation system based on the steering tie rod projection, which is disclosed in claim 1, is characterized in that the variable load simulation device is a programmable steering damper and is used for simulating nonlinear and time-varying steering resistance of the steering system under different soil or mixed working conditions by adjusting the damping coefficient of the variable load simulation device.
3. The light paddy field chassis variable steering damping physical simulation system based on the projection of a steering tie rod of claim 1, wherein the physical steering linkage mechanism comprises a knuckle arm, a steering tie rod and a steering butterfly disk, the steering butterfly disk is used for connecting an input acquisition module with the steering tie rod, and the steering tie rod is used for transmitting motion and force to the knuckle arm so as to drive the knuckle arm to deflect.
4. A paddy field light chassis variable steering damping physical simulation system based on tie rod projection according to claim 3, wherein the state sensing module comprises a steering arm rotation angle sensor arranged on a steering arm rotation shaft and used for measuring the rotation angle of the steering arm in real time, and taking the angle as a motion state parameter representing actual output of a steering system.
5. The paddy field light chassis variable steering damping physical simulation system based on steering tie rod projection of claim 1, wherein the processing control module is a vehicle-mounted embedded microcontroller; the vehicle-mounted embedded microcontroller is used for realizing real-time acquisition of sensor data, running the kinematic model and carrying out signal interaction with the physical simulation module.
6. The utility model provides a paddy field light chassis becomes damping of turning physical simulation method based on tie rod projection, is applied to a paddy field light chassis becomes damping of turning physical simulation system based on tie rod projection of claim 1~5, and characterized in that includes: s1, mapping a three-dimensional space geometric relation of a steering system to a low-dimensional calculation plane by the kinematic model, and dynamically calculating projection geometric parameters of each connecting rod of the steering system on the calculation plane according to preset three-dimensional space parameters; s2, receiving a steering input instruction, and calculating a theoretical steering output value by utilizing the kinematic model according to the steering input instruction and a plurality of steering system geometric parameters to be optimized; S3, driving a physical simulation module, and applying resistance load simulating external working conditions to the physical steering link mechanism through a variable load simulation device; s4, measuring an actual steering output value of the physical steering link mechanism under the resistance load in real time through a state sensing module, and comparing the actual steering output value with a preset ideal steering performance index to generate performance deviation; And S5, adjusting the geometric parameters of the steering system to be optimized according to the performance deviation, and repeating the steps S2 to S4 until the performance deviation meets the preset condition.
7. The paddy field light chassis variable steering damping physical simulation method based on tie rod projection according to claim 6, wherein in step S1, the preset three-dimensional space parameters at least include a caster angle (β) and an inward inclination angle (α) of a kingpin; the process of mapping the three-dimensional spatial geometry of the steering system to the low-dimensional computational plane by the kinematic model includes: And establishing a mapping relation between the three-dimensional space coordinate and the calculated plane coordinate by coordinate transformation based on the back tilt angle (beta) and the inner tilt angle (alpha).
8. The paddy field light chassis variable steering damping physical simulation method based on steering tie rod projection of claim 7, wherein the dynamically calculating the projection geometric parameters of each connecting rod of the steering system on the calculation plane specifically comprises: And dynamically calculating the effective length projection of the steering knuckle arm and the steering tie rod on the calculation plane according to the real-time motion gesture of the steering system.
9. The paddy field light chassis variable steering damping physical simulation method based on the steering tie rod projection according to claim 6, wherein in step S3, the variable load simulation device is a steering damper, the damping value of which is adjustable to simulate steering resistance of different soil conditions; the resistance load simulating the external working condition also comprises a gradual change or transient process simulating the resistance of the paddy field soil.
10. The paddy field light chassis variable steering damping physical simulation method based on tie rod projection according to claim 6, wherein in step S4, the preset ideal steering performance index is an ackerman corner relationship; The performance bias is quantitatively generated by calculating a root mean square error between the actual steering output value and an ideal steering value calculated based on an ackerman rotation angle relationship.

Description

Paddy field light chassis variable steering damping physical simulation system and method based on steering tie rod projection Technical Field The invention relates to the technical field of agricultural equipment, in particular to a paddy field light chassis variable steering damping physical simulation system and method based on steering tie rod projection. Background The light power chassis of paddy field is used as a walking platform for bearing farm implements such as rice transplanting machine and hill planter, and the operability and steering performance of the light power chassis of paddy field in paddy field environment directly influence the operation efficiency, crop quality and energy consumption. Paddy field soil generally exhibits a complex layered structure including a water layer, a mud layer, a cultivated layer and a hard bottom layer, and soil characteristics are highly nonlinear, uneven and time-varying, resulting in the steering wheel of the power chassis being subjected to a great and dynamically varying resistance during steering. At present, aiming at the design optimization of a paddy field light power chassis steering system, the industry mainly adopts a research and development flow of combining three-dimensional software simulation with a real vehicle test. With the rapid development of computer aided design and multi-body dynamics simulation software (such as CATIA, solidWorks, ADAMS), three-dimensional software simulation has become an early tool for steering system design, and can rapidly build geometric models and simulate basic kinematic characteristics. However, the existing three-dimensional software simulation method has significant defects: Firstly, complicated mechanical properties of paddy field soil, such as nonlinear change, gradual change and transient processes (such as transition from muddy state to hard state) of soil resistance, are difficult to accurately simulate, so that the deviation between a simulation model and actual working conditions is large; Secondly, the software model tends to simplify or ignore key parameters (such as the influence of caster angles and internal inclinations on a steering linkage system), so that simulation results lack high fidelity and parameter optimization (such as the length of a steering tie rod) cannot be effectively guided. The reason for these drawbacks is that soil mechanics modeling involves multiple physical field couplings (including fluid mechanics and soil mechanics), and existing software algorithms and databases are unable to handle these complex boundary conditions and uncertainties accurately in real-time. After software simulation, the developers typically go to a real-vehicle test phase to verify the design and optimize the parameters. The real vehicle test can provide real performance data, but has low efficiency, high cost and difficult control of test conditions. The method has the specific defects that firstly, parameter iteration optimization is long in time consumption, a prototype is required to be manufactured again when key geometric parameters (such as the length of a steering tie rod) are adjusted once, labor and material cost are increased, secondly, the repeatability of soil working conditions is poor, the real paddy field environment is affected by factors such as regions, seasons and water content, consistent test conditions cannot be reproduced accurately, especially for gradual change or transient soil resistance scenes, thirdly, the test range is limited, multiple soil types cannot be simulated in a laboratory environment, and therefore data collection and analysis efficiency is low. The main reason for these problems is that the real vehicle test depends on the external environment, and controllable load simulation and parameter adjustment cannot be realized, which limits the application of the real vehicle test in the early design stage. In summary, the prior art has faults between software simulation and real vehicle test, wherein the faults are low in reliability due to model distortion and insufficient soil simulation, and the faults are difficult to be used for large-scale parameter optimization due to high cost, low efficiency and uncontrollable conditions. In combination with the current state of the art, such as that the development of a steering system in the agricultural machinery field remains in an experience-dependent stage, the soil simulation technology does not realize high-fidelity laboratory simulation yet, and a novel semi-physical simulation system is urgently needed in the field, which can realize high-fidelity parameter optimization, flexibly simulate different soil working conditions in a laboratory environment, and bridge the gap between software simulation and real vehicle tests, so that the development cost is reduced, the period is shortened, and the design level is improved. Disclosure of Invention The invention aims to design a paddy field light chassis variable st