A mathematical model of tractor overturning and impact behaviour

Chisholm, C.J.

doi:10.1016/0021-8634(79)90079-9

Cited by 40 publications

(14 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Conceptualization of the General Idea of a System (→ Step 1.a) Following the specific approach for conceiving and designing a test system, it is necessary to define the typical situations leading to a sideways overturning or a lateral rollover of an agricultural machine. In particular, the overturning conditions are essentially three [37,68,69], possibly occurring together to outline many possible scenarios:…”

Section: Design Of the General System ('Test Rig')mentioning

confidence: 99%

Definition of the Layout for a New Facility to Test the Static and Dynamic Stability of Agricultural Vehicles Operating on Sloping Grounds

Bietresato

Mazzetto

2019

Applied Sciences

View full text Add to dashboard Cite

In this study, a new rig for investigating the static and dynamic stability of agricultural machines was conceived: its architecture was studied and its layout was designed following a specific conceptual approach. The first part of the proposed design process specifically addresses the test equipment and follows a ‘top-down’ logic starting from the requisites of the tests to perform. This approach alternates analysis and synthesis phases and exploits two important principles of the creative design process: functional analysis and decomposition, and kinematic inversion. During this process, many solutions (kinematic mechanisms, actuators) were proposed and discussed based on their advantages and disadvantages towards the definition of an optimal configuration. Therefore, the layout of a new mechanical system has been developed, which is supposed to steer subsequent and more detailed design-phases appropriately. The proposed facility has many innovative features compared to traditional test systems, in which vehicles are tested for lateral overturning under static conditions with the steering components (wheels/central joint for conventional/articulated vehicles) usually in a configuration corresponding only to a straight-path trajectory. Indeed, the present test rig is a mechanical installation with three degrees of freedom. It presents a wide plane, which can be tilted, composed by two semi-platforms connected by a central articulation hinge, operated by hydraulic jacks which allow the different angulations of the semi-platforms. It is specifically thought for performing dynamic stability tests of vehicles, especially on circular trajectories. An additional subsystem embedded in one of the two semi-platforms, configured as a rotating platform (‘turntable’), can test the global (static) stability of motionless vehicles placed on it.

show abstract

Section: Design Of the General System ('Test Rig')mentioning

confidence: 99%

Definition of the Layout for a New Facility to Test the Static and Dynamic Stability of Agricultural Vehicles Operating on Sloping Grounds

Bietresato

Mazzetto

2019

Applied Sciences

View full text Add to dashboard Cite

show abstract

“…• final phases of proposals and solutions with the design of innovative tractors, equipment/devices and new models of driver behaviour [41].…”

Section: Discussionmentioning

confidence: 99%

The Analysis of the Cause-Effect Relation between Tractor Overturns and Traumatic Lesions Suffered by Drivers and Passengers: A Crucial Step in the Reconstruction of Accident Dynamics and the Improvement of Prevention

et al. 2017

View full text Add to dashboard Cite

Abstract:The evaluation of the dynamics of accidents involving the overturning of farm tractors is difficult for both engineers and coroners. A clear reconstruction of the causes, vectorial forces, speed, acceleration, timing and direction of rear, front and side rollovers may be complicated by the complexity of the lesions, the absence of witnesses and the death of the operator, and sometimes also by multiple overturns. Careful analysis of the death scene, vehicle, traumatic lesions and their comparison with the mechanical structures of the vehicle and the morphology of the terrain, should help experts to reconstruct the dynamics of accidents and may help in the design of new preventive equipment and procedures.

show abstract

“…The direction of projection is parallel to the direction of the resultant force (applied to the vehicle's COG). A sideways overturning or a lateral rollover of an agricultural machine is not a so-rare event as it can be triggered by the existence of one (or more) of these three, quite common, conditions [8][9][10][11]…”

Section: Stability Issues and Causes Of Rollover Formentioning

confidence: 99%

Increasing the safety of agricultural machinery operating on sloping grounds by performing static and dynamic tests of stability on a new-concept facility

Bietresato¹,

Mazzetto²

2018

Int. J. SAFE

View full text Add to dashboard Cite

Using agricultural machines on slopes is very risky for operators: drivers difficultly have a correct perception of the stability condition of their vehicles when travelling, especially because it is impossible to instantly check the ground elevation and harshness in correspondence of each wheel. Moreover, the tests that are usually performed to characterize these machines' stability are scarcely helpful in real conditions: these tests check the lateral overturning (maximum angle) in two static configurations only. Evidently, these do not cover most of real situations, do not locate its centre-of-mass and do not consider the centrifugal force (causing load-transfers and dynamically-variable readjustments of the machine's trim in turnings), thus making impossible the setup of eventual active/passive safety-systems to be installed on vehicles.Therefore, with the aim of overcoming the limitations of actual tests, giving a higher level of information to the tractors' manufacturers and users, we have conceived a completely-new test-apparatus to be installed within our laboratory: the Tiltable Platform. It integrates two subsystems, illustrated hereinafter.(1) The tiltable/angleable plane is a wide flat structure (15×15 m), able to simulate different groundgradients, allowing a vehicle to manoeuvre/travel on it along circular paths in a controlled and safe environment. It can also generate an angle at half of its width, transversal to the maximum-slope direction (simulating the exits of an agricultural machine from the inter-rows). (2) The tilting turntable: has a circular shape and is divided into quadrants, each capable of measuring the weight sustained due to a motionless vehicle positioned on them; it is installed on a tilting structure and can rotate around a vertical axis, thus allowing to vary the angular position of the vehicle's longitudinal axis with reference to the maximum-slope direction.Finally, this test-rig will be useful to develop new test-methodologies to certify the agricultural machines' stability in real operating-conditions (e.g. operating with ballast/mounted-implements).

show abstract

A mathematical model of tractor overturning and impact behaviour

Cited by 40 publications

References 6 publications

Definition of the Layout for a New Facility to Test the Static and Dynamic Stability of Agricultural Vehicles Operating on Sloping Grounds

Definition of the Layout for a New Facility to Test the Static and Dynamic Stability of Agricultural Vehicles Operating on Sloping Grounds

The Analysis of the Cause-Effect Relation between Tractor Overturns and Traumatic Lesions Suffered by Drivers and Passengers: A Crucial Step in the Reconstruction of Accident Dynamics and the Improvement of Prevention

Increasing the safety of agricultural machinery operating on sloping grounds by performing static and dynamic tests of stability on a new-concept facility

Contact Info

Product

Resources

About