Evaluation of Tractor Ride Vibrations by Cab Suspension System

HighlightsTractor ride vibrations were evaluated under various conditions according to type of cab suspension.Ride vibrations were measured on flat and bumpy roads using four tractors with different cab suspension types.Tractors with hydro-pneumatic suspension exhibited smaller ride vibrations than tractors with rubber mounts.Semi-active hydro-pneumatic control resulted in smaller ride vibrations than those resulting from passive control.Abstract. In this study, tractor ride vibrations were evaluated under various conditions according to the type of cab suspension, and the effects of different cab support methods on these ride vibrations were determined. Ride vibrations on flat and bumpy roads were measured using four tractors equipped with different cab suspension types and were analyzed based on ISO Standard 2631-1 for human exposure to whole-body vibration. The ride vibration values were evaluated using the weighted root mean square acceleration and fourth-power vibration dose value. The results confirmed that the tractor equipped with semi-active hydro-pneumatic cab suspension at the two rear positions yielded smaller ride vibrations than the tractors with rubber mounts at all four positions. Vibration reduction effects of up to 53.8% and 67.1% were yielded in the flat road test and bumpy road test, respectively. In addition, among the two tractors with hydro-pneumatic cab suspension systems, ride vibrations were reduced by approximately 7.1% in the tractor that used semi-active control as compared to the tractor that used passive control. Keywords: Hydro-pneumatic cab suspension, Ride vibration, Rubber mount, Whole-body vibration.

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Body Orientation and Points of Contact during Laboratory-Based Machinery Egress: Investigating Adherence to Safety Guidelines

Journal of Agricultural Safety and Health ◽

10.13031/jash.13931 ◽

2020 ◽

Vol 26 (3) ◽

pp. 95-104

Author(s):

David C. Kingston ◽

Behzad Bashiri ◽

Abisola Omoniyi ◽

Catherine M. Trask

Keyword(s):

Injury Risk ◽

Whole Body Vibration ◽

Change Points ◽

Whole Body ◽

List Type ◽

Farm Machinery ◽

Body Vibration ◽

Contact Behavior ◽

Access Path ◽

Safety Guidelines

HighlightsMost of the experienced operators performed machine egress facing out from the cab.Egress was 2.5 s longer when facing in toward the machine, but no differences were observed in points of contact maintained when compared to egress facing out.Maintaining at least three points of contact during egress was observed for only approximately 30% of egress duration.A one-hour exposure to whole-body vibration did not change points of contact behavior nor egress duration when performing egress while facing out.Abstract. Mobile farm machinery operators are at a high risk of injury when entering (ingress) and exiting (egress) the cabs of such machinery due to slips and falls. Safety organizations and equipment manufacturers have delivered a consistent message: operators are to egress machines facing in, toward the access path, and maintain three points of contact at all times. This study used a laboratory-based model of a mid-sized agricultural tractor to determine adherence to best practices for safety and the effect of acute whole-body vibration exposure on compliance. The majority of 19 experienced operators (16 male, 3 female) performed machinery egress facing out from the cab because descending while facing in toward the machine took 2.5 s longer. Maintaining at least three points of contact during egress was observed for only approximately 30% of egress duration, but was as high as approximately 41% for participants who self-selected the facing-in orientation. Exposure to 1 h of whole-body vibration did not change points of contact behavior nor trial duration when performing egress while facing out. Overall, the model cab used in this study had safety features similar to a real-world machine, indicating that there may be opportunities in access path or cab door design to promote increased points of contact use. Future work is needed to accurately assess three-dimensional movement patterns and external forces for disease and injury risk models. Keywords: Access path, Farm machinery, Safety guidelines, Occupational injury.

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Evaluation of whole-body vibration exposure using a fourth power method and comparison with ISO 2631

Journal of Sound and Vibration ◽

10.1016/0022-460x(89)90541-5 ◽

1989 ◽

Vol 129 (1) ◽

pp. 143-154 ◽

Cited By ~ 7

Author(s):

P.-E. Boileau ◽

D. Turcot ◽

H. Scory

Keyword(s):

Whole Body Vibration ◽

Whole Body ◽

Fourth Power ◽

Vibration Exposure ◽

Power Method ◽

Body Vibration ◽

Iso 2631

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Three-axial evaluation of whole-body vibration in agricultural telehandlers: The effects of an active cab-suspension system

Journal of Occupational and Environmental Hygiene ◽

10.1080/15459624.2017.1334899 ◽

2017 ◽

Vol 14 (10) ◽

pp. 758-770 ◽

Cited By ~ 2

Author(s):

Federica Caffaro ◽

Christian Preti ◽

Margherita Micheletti Cremasco ◽

Eugenio Cavallo

Keyword(s):

Whole Body Vibration ◽

Suspension System ◽

Whole Body ◽

Body Vibration ◽

Cab Suspension

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A Literature Survey of Biodynamic Models for Whole Body Vibration and Vehicle Ride Comfort

Volume 6: 1st Biennial International Conference on Dynamics for Design; 14th International Conference on Advanced Vehicle Technologies ◽

10.1115/detc2012-71061 ◽

2012 ◽

Cited By ~ 2

Author(s):

Prasad Bhagwan Kumbhar ◽

Peijun Xu ◽

Jingzhou (James) Yang

Keyword(s):

Human Body ◽

Ride Comfort ◽

Whole Body Vibration ◽

Element Model ◽

Rigid Bodies ◽

Literature Survey ◽

Whole Body ◽

Fourth Power ◽

Fe Model ◽

Body Vibration

Vehicle ride comfort plays an important role in the vehicle design. Human body is very sensitive to whole body vibration. Vehicle ride comfort has brought lots of concerns in recent years due to requirement of better ride comfort performance for newly developed vehicles. Vehicle ride comfort has a direct effect on driver’s performance and will result in overall customer satisfaction. Various papers have reported vehicle ride comfort and various biodynamic models have been built in the literature. However, there is a lack of a comprehensive literature survey to summarize all biodynamic models for whole body vibration and vehicle ride comfort. The purpose of this paper is to have a literature review of biodynamic models. So this paper initially focuses on various health issues due to whole body vibrations. Whole body vibration transfers environmental vibration to human body through a large contact area. Vibration evaluation methods such as weighted root mean square (r.m.s.) acceleration method, fourth power VDV method are discussed. Along with that the paper will focus on various biodynamic response functions. Human models in the literature are divided into three main groups: lumped parameter (LP), finite element model (FE), and multibody model (MB). In the LP model, human body is represented by several concentrated masses which are connected by springs and dampers. The FE model considers that human body consists of numerous finite elements. And in MB model, human body is made of several rigid bodies connected by bushing element for both translational and rotational motion. So this paper thoroughly summarizes various models developed to reduce human body vibration. At the end, four different approaches of assessing ride comfort are summarized. These four approaches are ride measurement in vehicles, ride simulator test, shaker table test and subjective ride measurement.

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