刘九庆 姚凯

摘 要：建立履带底盘式森林灭火炮的转向分析模型时，因忽略质心偏移和离心力所产生的问题，会导致不能更真实地体现森林灭火炮转向运动的状态。为此本文基于履带转向原理和转向动力学，对森林灭火炮的履带底盘做动力学分析和静力学分析，建立更为准确的森林灭火炮转向性能数学模型，在建立模型时考虑了转向阻力矩、土壤下陷阻力和履带接地面压力分布情况等参数。选取实际车辆为例，用所建立模型计算各项参数，并与试验结果作对比。结果表明：履带车体因离心力产生的质心偏移量越大，履带转弯半径也越大。森林灭火炮转向性能受离心力影响较大，履带对地面的压力并不是均布在履带接地表面上。试验表明模型分析的结果与实际情况的误差在可接受范围内，证明了模型的准确性。

关键词：履带底盘;转向过程;离心力;阻力矩;转向理论

中图分类号：S776;TH113.2    文献标识码：A   文章编号：1006-8023（2021）03-0095-08

Abstract：When establishing the steering analysis model of crawler bottomplate forest fire extinguishing cannon， the ignoring of the problems caused by the offset of the center of mass and the centrifugal force will lead to the failure to more truly reflect the state of the steering moment of the forest fire extinguishing cannon. For this reason， based on the principle of track steering and steering dynamics， this paper makes dynamic analysis and statics analysis of the crawler chassis of forest fire extinguishing cannon， and establishes a more accurate mathematical model of forest fire extinguishing cannon to performance when the model takes into account the steering resistance moment， soil subsidence resistance， track parameters such as ground pressure distribution. Taking a real vehicle as an example， the parameters are calculated by the model and compared with the test results. The results show that the larger the centroid offset caused by centrifugal force is， the larger the turning radius of the track is. The steering performance of forest fire extinguishing cannon is greatly affected by the centrifugal force， the pressure from the track to the ground is not uniformly distributed on the ground surface of the track. The experiment also shows that the error between the results of model analysis and the actual situation is within the acceptable range， which proves the accuracy of the model.

Keywords：Crawler chassis; steering process; centrifugal force; drag torque; steering theory

0 引言

履帶式行走机构能适应复杂的路况，有着良好的行驶能力、较高的机动性，正因如此，履带式底盘是特种车辆行驶系统的首选，如森林灭火炮的行走系统。提升特种车辆的工作效率方法之一便是改进履带底盘的转向性能[1]，转向能力的好坏直接决定了履带行驶能力的高低[2]。目前为止，众多学者们在这一方面也取得了一定的研究成果，国外学者有加拿大WONG[3]、日本KITANO等[4]。其中，Al—Milli等[5]研究时，并未考虑离心力会带来质心偏移的结果。……