【正文】 提升。在本課題研究設(shè)計過程中由于時間較倉促未能設(shè)計出程序，讓該裝置進(jìn)行轉(zhuǎn)動慣量的自動測算。以后在工作學(xué)習(xí)中將加強軟件方面的鍛煉。江蘇技術(shù)師范學(xué)院畢業(yè)論文致 謝畢業(yè)設(shè)計，是我大學(xué)生涯交上的最后一份作業(yè)。我的畢業(yè)指導(dǎo)老師梁瑩林老師給了我們巨大的支持與幫助，使我能夠順利完成畢業(yè)設(shè)計，在此表示衷心的感激。感謝這篇論文所涉及到的各位學(xué)者。本文引用了數(shù)位學(xué)者的研究文獻(xiàn)，如果沒有各位學(xué)者的研究成果的幫助和啟發(fā)，我將很難完成本篇論文的寫作。感謝我的同學(xué)和朋友，在我寫論文的過程中給予我了很多你問素材，還在論文的撰寫和排版燈過程中提供熱情的幫助。由于我的學(xué)術(shù)水平有限，所寫論文難免有不足之處，懇請各位老師和學(xué)友批評和指正！江蘇技術(shù)師范學(xué)院畢業(yè)論文附 錄附錄1 實驗輔助裝置的電路圖 附錄2 實驗輔助裝置的裝配圖江蘇技術(shù)師范學(xué)院畢業(yè)論文外文資料原文ZBIGNIEW DWORECKI, ANDRZEJ FISZER, MARIUSZ ?OBODA, JACEK PRZYBY?Institute of Agricultural Engineering Agricultural University of Poznan, PolandCALCULATION OF TRACTOR AND AGRICULTURAL MACHINES MOMENTSOF INERTIASummaryDetermination of tractor moments of inertia is not so easy. There are known few methods of indirect measurement of moment of inertia, but the hanging tractor is necessary in this methods. Suspension of the tractor is a long shot. This is the reason, that most of authors assume the quantity of moment of inertia only intuitionally, without measurements, in their putation. Tractor moments of inertia can be evaluated through “geometricmass” tractor model. Main tractor elements, like corps, wheels, cabin, wheel reduction gears, halfshafts, can be admitted by non plicated geometric body, like cylinder, ring, cone, rectangular, torus, plate, box constructed from plate. Dimensions and weightiness of this geometric body must be the same that tractor units. The main moments of inertia of this solid are easily calculated. Steiner principle provide calculation main moments of inertia of all tractor body. These moments of inertia were applied in mathematical models of the tractor, built for eigenfrequencies calculation. Tractor vibrations were measured for verification of the models. These measured frequencies were similar to frequencies calculated from received models. It means, that suggested method of tractor moments of inertia determination, is accurate. This easy method allows to leave out big mistakes in calculation of tractor free vibrations frequencies.1. IntroductionThe farm tractor is the farmer’s basic tool. Consequently, it is also his frequent workplace. In performing their work in the field, tractor operators are exposed to dust, noise, warm cold weather (temperature), precipitation (rain) and mechanical vibrations. The tractor cab may eliminate dust, noise and precipitation. Airconditioned cab may eliminate effect of temperature, and, provided the cab is suspended on springs, partially eliminate vibrations. The vibrations affecting the driver may be generated by the engine, machinery attached to the tractor and tractor wheels (collisions with obstacles). Vibrations generated by the engine and machinery attached to the tractor are insignificant in present engines and machines. Vibrations generated by tractor wheels may be detrimental to human body organs, because the frequency of tractor vibration can be the same that eigenfrequency of human body hazardous are the highamplitude and lowfrequency vibrations which can cause damage to many human body organs. Frequencies of tractor vibrations are a bination of tractor eigenfrequencies and depend on excitation. Tractor eigenfrequencies we can to get to know if we build mathematical model of the tractor.2. Model of the tractorA dynamic model may be created by using many is no need to prove that the finite element method is too accurate for our purposes. It is so because of the big discrepancy between the rigidities of tires and the driver39。s seat springsuspension system and the rigidities of other parts of the tractor. Therefore such units are analysed with the use of the concentrated mass method. Literature (Mitschke, 1989。 G246。hlich, 1991。 Graef, 1976) abounds with models of vehicles, including models of tractors. However sometimes, such models do not account for the differences between a typical truck and tractor such as the lack of suspension of the rear axle and the degree of swinging of the tractor front axle. The simplest models of the tractor which may be accepted, can be created in lateral plane and front plane of the tractor (fig. 1 and 2). The mode (shape) of vibrations in lateral plane tractor model is vertical and pitch. The mode of vibrations in front plane is vertical and mathematical formula of lateral plane tractor model shown on fig. 1 is:Fig. 1. Lateral plane tractor model: m mass of the system, Jb pitch moment of inertia of the system, k1the sum of front tyres stiffness, k2 the sum of rear tyres stiffness, ?a” wheel base (rear axle to front axle), l front axle to centre of gravity calculated by changes of the wheels load with simultaneous measurements of ground reaction with the accuracy of 1N and the resulting deflections with 0,01 mm accuracy. The mathematical formula of front plane tractor model shown on fig. 2 is: Fig. 2. Front plane tractor model: m mass of the system,Jc roll moment of inertia of the system, k1,2 the sum of one front and one rear tyre stiffness, r track of wheels For calculation the frequency from presented formulas, it is necessary to know the quantity of all the parameters from right side of the mass and the geometric parameters “a” (wheel base,rear axle to front axle) and “r” (track of wheels) may be found by using factory specifications or by weighing and measuring. The ?l” distance (front axle to centre of gravity) may be calculated by using factory specifications of axle loads. The measuring of vertical stiffness of front and rear tyres is also not difficult. The rigidity of tires may be calculated by changes of the wheels load with simultaneous measurements of ground reaction with the accuracy of 1N and the resulting deflections with 0,01 mm accuracy.3. Calculation of moments of inertiaThe mass moment of inertia of the tractor relative to the frontback axis and leftright axis, cutting through the