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ABSTRACT. Vehicle and troop tracking systems are increasingly being used during military training events to improve the quality of the training by providing detailed information for real-time and post training [...]

ABSTRACT. Vehicle tracking systems were installed on four military vehicles (M813 cargo truck, M998 utility vehicle, M548A cargo carrier, M1025 utility vehicle) at Camp Atterbury, Indiana to assess the impact [...]

ABSTRACT. Geographic Positioning System (GPS) based vehicle tracking systems were installed on three military vehicle types (M88 tank recovery vehicle, M35A3 cargo truck, and M1009 utility cargo vehicle) at Camp [...]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2005.10.012 Byline: Jeffrey R. Foster (a), Paul D. Ayers (b), Angela M. Lombardi-Przybylowicz (c), Katie Simmons (b) Keywords: Ecological impact; Grasslands; Military training; Disturbance Abstract: Sustainable use of military training lands requires understanding and prediction of the effects of military vehicles on vegetation. We examined the initial impacts of an 8-wheeled, light armored vehicle (LAV) on grassland vegetation at Fort Lewis, Washington. The LAV drove replicate spiral paths at two starting velocities, 10.3 and 5.1ms.sup.-1. The disturbed width (width of ground impacted by the tires) increased as turning radius decreased, but was unaffected by vehicle velocity. An inverse-exponential model predicted disturbed width (r.sup.2=0.68) at all turning radii for both velocities combined. In low-velocity spirals, and for straight tracking (turning radius>40m) and moderate turns (radius 20-40m) in high-velocity spirals, all vegetation damage was imprint (plants flattened by wheels). During sharp (radius moderate turns>sharp turns in high-velocity spirals. In low-velocity spirals, post-tracking cover of several plant growth forms (non-native species, perennial species, sod-forming grasses) was similar to pre-tracking cover, but in high-velocity spirals, post-tracking cover of these growth forms decreased in the order straight[greater than or equal to]moderate=sharp. Cover of native species and forbs decreased more in high- than in low-velocity spirals, but was unaffected by curvature. Pre- and post-tracking cover of annual species, bunchgrasses, and shrubs was a[c]1/23%. The most severe vegetation damage caused by operation of wheeled LAVs on grasslands is associated with sharp, high-velocity turns. Author Affiliation: (a) Environmental & Natural Resources Division, Public Works, IMNW-LEW-PWE, MS 17, Box 339500, Fort Lewis, WA 98433-9500, USA (b) Department of Biosystems Engineering and Environmental Science, University of Tennessee -- Knoxville, 2506 E.J. Chapman Drive, Knoxville, TN 87996, USA (c) Integrated Training Area Management Program, IMNW-LEW-PLT-R, Box 339500, MS 16c, Fort Lewis, WA 98433-9500, USA Article History: Received 4 January 2005; Revised 22 August 2005; Accepted 6 October 2005

Agricultural production has clearly benefited from the development of the tractor. The tractor provides a traction device and mobile power source. However, operating large equipment with high clearance on uneven ground leads to stability and overturn issues. Around the world, tractor overturns are still a leading cause of agricultural production fatalities. This special issue of the Journal of Agricultural Safety and Health focuses on recent research on tractor ROPS (rollover protective structures) and stability. Engineers and scientists in both Italy and the U.S. have been working on these topics, attempting to solve old problems and address rising issues. Understanding the factors leading to tractor instability, investigating the structures protecting the operator, and examining the continuous roll potential will all lead to increased operator protection and reduced fatalities., (Copyright© by the American Society of Agricultural Engineers.)

Tractor overturn is the leading cause of agricultural fatalities in the U.S. Most of these fatalities can be eliminated using a rollover protective structure (ROPS) and a seatbelt. Unfortunately, not all agricultural tractors designed to support ROPS have ROPS designs. A computer-based ROPS design program (CRDP) was developed and successfully tested to provide quick and simple two-post, rear axle-mounted ROPS designs based on SAE Standard J2194. The program uses the tractor dimensions and mass to calculate the dimensions needed for ROPS components. Excel was used as the framework to provide the input, calculation, and ROPS drawing worksheets. Three ROPS (for Massey Ferguson 265, Long 460, and Allis Chalmers 5040 tractors) were designed and constructed using the CRDP. Static rear, side, and vertical tests were conducted based on SAE J2194 on two of the ROPS. All ROPS performance deflection (RPD) tests were less than the ROPS allowable deflection (RAD), indicating that the ROPS passed the static tests. The third ROPS was successfully mounted on the tractor axle housing within one hour, demonstrating the ease of installation using a bolted corner bracket design. Although the CRDP provided quick and simple ROPS designs, this program does not eliminate the requirement to conduct and pass the performance tests for ROPS designs specified in OSHA and SAE standards., (Copyright© by the American Society of Agricultural Engineers.)

The number of fatalities caused by tractor rollovers has decreased in recent years, but the number of fatal tractor rollover accidents with a folded-down rollover protective structure (ROPS) has increased. Operating a ROPS-equipped tractor in low overhead clearance zones is difficult and sometimes impossible. The foldable ROPS (FROPS) was designed to solve the rigid ROPS problem, but lowering and raising a conventional FROPS is a time-consuming and strenuous process. After operators fold down a FROPS to pass a low overhead clearance zone, some prefer to leave it in the folded or inoperative position, increasing the risk of a rollover fatality. The actuation forces for raising and lowering a FROPS are not well known and may be influenced by actuation speed. A completely randomized block design with two blocks, five levels of speed, and multiple replications was conducted to investigate the effect of speed on actuation torque. The blocks were two sizes of tractor FROPS. The test included five levels of speed, including two levels of static measurement and three levels of dynamic measurement. A variable-speed motor system was used to control the speed for raising and lowering the FROPS. The actuation torque is a function of the FROPS upper part shape, dimensions, material density, turning acceleration, and friction. A theoretical model was developed to predict the actuation torque based on the FROPS shape, dimensions, and material density. For one ROPS, due to friction, the dynamic actuation torque was greater for raising and less for lowering than the theoretical torque. Indicator variable regression was used to analyze the effect of speed on actuation torque. Results showed that speed had a significant (p > 0.05) effect on actuation torque. Although there were statistically significant differences between the dynamic actuation torques, these differences were relatively small and negligible compared to the differences between the static torques., (Copyright© by the American Society of Agricultural Engineers.)