ISTVS embarked on a project in 2016 that aims at updating the current ISTVS standards related to nomenclature, definitions, and measurement techniques for modelling, parameterizing, and, respectively, testing and validation of soft soil parameters and vehicle running gear-terrain interaction. As part of this project, a comprehensive literature review was conducted on the parameterization of fundamental terramechanics models. Soil parameters of the empirical models to assess off-road vehicle mobility, and parameters of the models to characterize the response of the terrain interacting with running gears or plates from the existing terramechanics literature and other researchers' reports were identified. This review documents and summarizes the modelling approaches that may be applicable to real-time applications of terramechanics in simulation, as well as in controller design.
A full-term Arabian filly (C1) was admitted to Equicare approximately 2.5 hours after unassisted birth. The owner reported that the foal revealed dorsiflexion of the head and neck and seizure activity immediately after birth. The foal had a weak suck reflex and was unable to stand. The dam of this foal (F4) had produced 3 other foals before this foal, all sired by the same stallion (M2*) (Fig 1). The owner reported that the mare's first foal, a colt (U1), had dilute coat color and neurologic signs. The colt had a difficult birth and was nursed for 2 days because the owner thought it was suffering from neonatal maladjustment syndrome (NMS). After 2 days, the colt remained recumbent and was euthanized. The next 2 foals that the mare produced were normal (N1 and N2). All 3 previous gestations had been of normal length.The foal presented in lateral recumbency exhibiting marked neurologic signs including spontaneous paddling, head banging, and opisthotonus. The coat was a dilute lavender color (Fig 2), body weight was 46 kg, and the foal was in good condition. Rectal temperature was normal, with increased heart (150 beats per minute) and respiratory (60 breaths per minute) rates. The mucous membranes were congested. Capillary refill time (CRT) and hydration were normal. A weak suck reflex was present. The umbilicus appeared macroscopically normal. On neurologic examination, the foal was hyperesthetic to tactile stimulation. The foal could lie only in right lateral recumbency because of torticollis to the left. Direct and consensual pupillary light reflex (PLR) and blink-to-bright-light reflex were present. Temporary, spontaneous ventral strabismus and horizontal nystagmus were evident with the foal in lateral recumbency. The foal vocalized in response to auditory stimulus. Local cervical, cervicofacial, cutaneous truncal, and flexor reflexes of the forelimbs and hindlimbs were present, but assessment was followed by an exaggerated response characterized by paddling, extensor rigidity, and opisthotonus. Triceps, patellar, and perineal reflexes were normal.
With all wheeled vehicles, the tire contact patch is the only connection between the vehicle and the road. All the forces, except for aerodynamic forces, that are acting on the vehicle are generated in the tire contact patch. The size, shape and the pressure distribution of the contact patch are important to the performance, ride qualities and handling characteristics of a vehicle. Tire footprint studies are essential in understanding tire force generation and tire wear mechanisms. It is thus important to accurately determine the tire contact patch size and dimensions. This paper discusses various methods for measuring the static tire contact patch dimensions. A set of tests are conducted on various tires and at different inflation pressures. These tests are used to discuss the suitability of the methods depending on the type, size, load and contact surface of the tire. A list of advantages and disadvantages for each method is generated and discussed. The aim of this paper is not to study the tire footprints but to discuss the various testing methods. Insight into the different methods can help to select the suitable method for future tire contact studies.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with đź’™ for researchers
Part of the Research Solutions Family.