Tire Inflation Pressure Research Articles

Tyre Configuration and Axle Load of Front-Wheel Assist and Four-Wheel Drive Tractors Effects on Soil Compaction and Rolling Resistance under No-Tillage

Selecting the appropriate tyre configuration and settings for heavy farm vehicles is important to ensure that soil compaction and power loss in rolling resistance are minimised and traction is optimised. This study investigated the effect of front-wheel assist (FWA, ≈75 kN) and four-wheel drive (4 WD, ≈100 kN) tractors fitted with different tyre configurations (single, dual), tyre sizes and inflation pressures on soil strength (a proxy for soil compaction), and rolling resistance. Single-pass tests were performed on a Typic Argiudoll (≈23% clay, bulk density: 1305 kg m−3) managed under permanent no-tillage. Results showed that average power losses in rolling resistance were 7.5 kN and 5 kN for the 4 WD and FWA tractors, respectively. The average rut depth increased by approximately 1.4 times after a pass of the 4 WD compared with the FWA tractor. The soil cone index (0–600 mm depth) increased from 2023 kPa (before traffic) to 2188 and 2435 kPa after single passes of the FWA and 4WD tractors, respectively (p < 0.05). At the centreline of the tyre rut, dual tyres reduced the soil cone index a little compared with single tyres, but they significantly increased the volume of soil over which soil strength, and therefore soil compaction, was increased. For both tractors (regardless of tyre configuration or settings), soil strength increased to the full measured depth (600 mm), but relative changes before vs. after traffic became progressively smaller with increased soil depth. The power loss in rolling resistance was consistently greater with the heavier tractor, and rut depth was directly related to tyre inflation pressure.

Triaxial Contact Stresses of the Green Bus Tire Including Complex Rubber Materials and Rim

The primary purpose of the research is to explore triaxial contact stresses of the green bus tire including complex rubber materials and rim. An accurate finite element model of the bus tire is constructed using ABAQUS software after verification. The measured and calculated values have good consistency under different tire loads and inflation pressures. The finite element model is applied for quantitative research by changing tire loads, inflation pressures, and rolling conditions. The analysis results show that higher inflation pressure increases vertical contact stress, which requires a reasonable balance between high load and high inflation pressure. When the inflation pressure increases, the position of the maximum longitudinal contact stress shifts forward, and the maximum transverse contact stress shifts inboard in the transverse direction. When the tire load becomes larger at the free rolling condition, the position of the maximum vertical contact stress moves forward, and the position at the full braking condition is more advanced under the same load conditions. Overload not only causes great damage to the tire during the braking condition but also accelerates the appearance of the rutting and shoving of the road.

The use of artificial intelligence methods in the analysis of the results of vehicle braking deceleration tests in the diagnostics of the braking system of a motor vehicle

The article presents the concept of using an artificial neural network to approximate the parameters describing the vehicle braking process, from the point of view of the application of this method in the diagnostics of the braking system. The artificial neural network of non-linear autoregression was used to approximate the dependence of the braking deceleration and the pressure in the braking system. The effectiveness of the neural network was checked depending on the number of neurons in its hidden layer and on the applied learning algorithm. The operation of the neural network was verified based on the actual braking processes of the Skoda Octavia, carried out with different dynamics, with different car weights and different tire inflation pressures. After verifying the neural network, it was used to approximate the braking deceleration values for the pressure values exceeding those present in the input data set. This action allows the analysis of the possibility of the vehicle obtaining a braking deceleration, which qualifies its braking system as efficient. Two concepts of using a neural network to solve this problem were analyzed. Conclusions related to the validity of the development of the discussed methods were drawn.

The effects of traffic management systems on the yield and economics of crops grown in deep, shallow and zero tilled sandy loam soil over eight years.

This paper reports on a 3 × 3 factorial study to consider the effects of controlled traffic (CTF), low tyre inflation pressure (high flexion) tyres (LTP) and standard tyre inflation pressure (STP) farming systems for deep, shallow and zero tillage practices on the yield of wheat, barley, oats and field beans grown in a sandy loam soil in the UK. The main effect of tillage showed that the zero tillage option significantly (***P < 0.001) reduced crop yields in four out of the five of the first crop years, with no significant effect in years two, six and eight and exceeded the yield of the other tillage treatments in year seven. The specific costs of the alternative tillage systems were estimated, from which the cost saving for zero tillage compared to deep tillage was c. £ 60 ha−1 (US$ 80 ha−1), which compensated for the overall loss in yield. There were no significant differences between the crop yields from the deep and shallow tillage treatments, with shallow tillage offering savings in operational costs of c. £ 30 ha−1 (US$ 40 ha−1). Overall, the controlled traffic farming system, where 30% of the field was trafficked, produced 4% greater crop yields (*P < 0.05), worth £ 39 ha−1 (US$ 53 ha−1) than standard tyre inflation pressures (STP). The estimated effect of reducing the trafficked area to 15% resulted in a further 3% increase in mean yield with a corresponding total increase in crop value of 7% worth £ 74 ha−1 (US$ 100 ha−1) compared to the STP system. The beneficial effect of low inflation pressure tyres (70 kPa and 80 kPa) on crop yields, for the deep tillage treatment, was significantly greater (*P < 0.05) than those of the standard tyre pressure system (100 kPa to 150 kPa) returning an average 3.9% additional crop yield over the period of the experiment worth £ 39 ha−1 (US$ 53 ha−1).

Modelling of the Vertical Dynamics of an Electric Kick Scooter

Nowadays, micro-mobility is one of the major global trends in cities for the innovation of the transport system. In this context a breakthrough introduction of electric kick scooters (e-scooters) has taken place. Unfortunately, these mobility systems cause several accidents mainly for two reasons: wrong use and inadequate safety requirements. Since e-scooters are quite a new type of vehicle, generally accepted mathematical models are yet to be developed. These models can be useful in understanding the dynamical properties of this type of vehicle thus improving its design to reduce riding accidents. The present paper presents a model for the simulation of the vertical dynamic behavior of e-scooters that accounts also for the mechanical impedance of the driver, thus allowing to estimate the overall driver’s comfort and road holding capabilities providing information on possible speed limitations in case of bad road conditions. Furthermore, the paper shows experimental envelope curves for lumped obstacles obtained with a dedicated test bench on which the e-scooter is fixed and tested under different conditions of vertical load and tire inflation pressure.

Method for determining of aircraft landing performance by the simulation modeling

The paper considers the method for determining of aircraft landing performance, the basic of which is landing roll depending on the type and tire inflation pressure, runway surface condition, aircraft weight, availability of brake parachutes. The given results are received by the simulation modeling of aircraft spatial movement on a landing mode. The model of aircraft dynamics includes modules of aircraft movement kinematic parameters calculation, engine thrust, landing gear ground reaction, retarding force in wheel brakes and brake parachutes. Adequacy and reliability of the designed model of aircraft movement is confirmed by comparison of values of movement kinematic parameters obtained as a result of simulation modeling, and the parameters received from a real flight of the maneuverable aircraft. The designed simulation model allows us to analyze change of aircraft movement kinematic parameters, defining its flight mode. By the results of the conducted study, it has been defined that halving of normal operational pressure in MLG wheels decreases aircraft landing roll by over forty per cent. Installation of КТ-163D wheels instead of КТ-251А reduces landing roll by approximately a factor of one and a half times, use of brake parachutes reduces aircraft landing roll almost twice at landing on an icy runway. The introduced method is recommended to be used while studying aircraft landing performance during its design or modernization. It is also suggested to integrate the designed method for determining landing performance as a part of on-board information and control system with the view of immediate aircraft landing performance determination in real-time operation in specific flight conditions.

Slurry Spreading on a Silt Loam Soil: Influence of Tyre Inflation Pressure, Number of Passages, Machinery Choice and Tillage Method on Physical Soil Quality and Sugar Beet Growth

Soil compaction forms a major threat to the well-functioning of agricultural soils. This threat is primarily driven by the increasing wheel loads of modern farming machinery and the increased frequency of field operations in periods when the soil is moist to wet and thus more prone to compaction. The application of slurry in early spring can have a highly detrimental impact, certainly for a crop like sugar beet, which is sensitive to soil compaction. A one-year experiment was set up on silt loam soil in the Belgian loess belt to assess the short-term impact of this field operation on soil under conventional ploughing and under non-inversion tillage. Two types of farming machinery were compared: a widely used tractor-trailer combination and a less common self-propelled slurry spreader, with the latter having higher wheel loads. Both machines were operated according to common or standard practice and a practice that aims at preventing soil compaction. For the tractor-trailer, this was with tyre inflation pressure recommended for road traffic and field traffic, respectively, corresponding with high and low tyre inflation pressure. The self-propelled slurry spreader was operated under standard and crab steering, respectively. Lowering the tyre inflation pressure to the recommended level for field traffic limited soil compaction and sugar beet yield loss. Although the effects of crab steering were less pronounced, it lowered the impact on the soil by limiting the number of passages. The overall machinery effect remained limited. The heavier self-propelled slurry spreader did not significantly increase the level of soil compactness and reduce sugar beet yield compared to the more common tractor-trailer combination. Soil under conventional ploughing showed more soil compaction, while the effectiveness of reducing tyre inflation pressure as a prevention strategy was lower compared to non-inversion tillage. The tillage practice, however, did not have any overall influence on sugar beet yield.

Tire Contact Force Equations for Vision-Based Vehicle Weight Identification

Overloaded vehicles have a variety of adverse effects; they not only damage pavements, bridges, and other infrastructure but also threaten the safety of human life. Therefore, it is necessary to address the problem of overloading, and this requires the accurate identification of the vehicle weight. Many methods have been used to identify vehicle weights. Most of them use contact methods that require sensors attached to or embedded in the road or bridge, which have disadvantages such as high cost, low accuracy, and poor durability. The authors have developed a vehicle weight identification method based on computer vision. The methodology identifies the tire–road contact force by establishing the relationship using the tire vertical deflection, which is extracted using computer vision techniques from the tire image. The focus of the present paper is to study the tire–road contact mechanism and develop tire contact force equations. Theoretical derivations and numerical simulations were conducted first to establish the tire force–deformation equations. The proposed vision-based vehicle weight identification method was then validated with field experiments using two passenger cars and two trucks. The effects of different tire specifications, loads, and inflation pressures were studied as well. The experiment showed that the results predicted by the proposed method agreed well with the measured results. Compared with the traditional method, the developed method based on tire mechanics and computer vision has the advantages of high accuracy and efficiency, easy operation, low cost, and there is no need to lay out sensors; thus, it provides a new approach to vehicle weighing.

Numerical Analysis of Standing Waves Phenomenon of Aircraft Tires.

In this paper, the generation mechanisms of standing waves on aircraft tires are discussed by comparing the time-domain model and FEA model. Unlike passenger car tires, aircraft tires accelerate to landing speed sharply when the airplane lands. According to the tire structure, the detailed finite element model of the aircraft tires is established in ABAQUS. The tire model runs on a 1.7 m spinning drum and accelerates to 300 km/h in 0.3 s. The proposed finite element model is verified by comparing the simulation results under inflation and static load with the experimental results. Similarly, by analyzing and comparing the calculated values of the time-domain model and FEA model, the variation of standing wave wavelength at different speeds is studied. In addition, the stress and strain field of the aircraft tires standing wave is analyzed. According to the definition of tire standing wave, a method for determining critical speed is proposed. Finally, the effects of tire inflation pressure and vertical load on the occurrence of standing waves were studied.

Non-contact vehicle weighing method based on tire-road contact model and computer vision techniques

Vehicle overloading is a very common phenomenon. The overloaded vehicles not only cause severe damage to the road/bridge and shorten its service life, but also likely lead to traffic accidents. Therefore, the identification of vehicle load is of great importance to the management of overload vehicles and can also provide valuable information for the design and maintenance of transportation infrastructures. The commonly used vehicle weighing methods including static weighing, pavement weigh-in-motion (PWIM), and bridge weigh-in-motion (BWIM) are contact technologies with weakness such as cumbersome installation, poor durability, short service life, and high maintenance cost. It is desirable to have a non-contact vehicle weight identification method without any sensor or scales on/under the road and bridge. Thus, the present study proposed a non-contact method based on the tire-road contact model and computer vision techniques. Firstly, the tire-road contact model is theoretically derived based on the Hertz contact theory, and the relationship between the tire vertical force and the tire deformation is obtained. Then, computer vision techniques such as the image segmentation and character recognition are adopted for the identification of the tire deformation and inflation pressure that are combined with the theoretical model to determine the tire vertical force and then the vehicle weight. Finally, the field test on passenger cars and trucks are conducted to verify the proposed method. The results indicate that the proposed method has a better performance than those methods in the literature, and shows a high accuracy and robust performance in vehicle weight identification under different conditions of inflation pressure, vehicle weight, motion state, and tire type.

TYRE PROFILE ARITHMETIC AND PERFORMANCE PARAMETER: A REVIEW OF VEHICLE USERS AND VULCANIZERS’ COGNIZANCE ON CAR TYRE MAINTENANCE TO CURB ROAD ACCIDENTS

Ageing car tyres are a hidden hazard and recipe for road accidents. Many vehicle users and their cohorts seem unconcerned and ignorant about tyre profile and its implications on human lives and livelihood. This study reviewed car users’ and vulcanizers’ comprehension of basic arithmetic of vehicle tyre profile to instigate best practices as well as instil proper maintenance culture. Out of 307 participants, purposive and convenient sampling were employed to select 292 vehicle users and a snowball to contact 15 vulcanizers. Results after a short interview analysis revealed that car users are aware of tyre inflation pressure and could identify the rim diameter of car tyres. Meanwhile, a significant number of users couldn’t tell where to locate their vehicle tyre specification details on their cars and were also unable to interpret tyre profiles including; tyre life cycle, tyre blend, tyre speed rating and load index. Although the majority of the vehicle users carried spare tyres, most of them do not check the conditions of their spare tyres until they are in need. Responses from vulcanizers revealed that most vehicle users do not bother about tyre expiry dates but rather prefer tyre fixing to tyre replacements. It is recommended that the Leaders of Transport Unions of commercial vehicles need to ensure proper load weight of vehicles before setting off from their terminals. Drivers and Vehicle License Authority (DVLA) needs to ensure healthy tyre condition before issuing roadworthy certificates. National Road Safety Authority (NRSA) must maximize sensitization campaigns towards proper tyre maintenance practices to reduce tyre failure accidents.

A mobility model for a tethered skidder

ABSTRACT Tethered logging has been rapidly increasing in popularity in many regions following developments in Europe and New Zealand. The main application in Europe has focused on using an integral winch to assist harvesters and forwarders. In New Zealand, the application has focused on a remote winch to stabilize and assist a feller-buncher, permitting cutting and bunching of whole trees for extraction by cable yarding, or in some cases shovel logging. In areas where cable yarding equipment is not available, a tethered skidder could be an alternative for moving bunched trees from the field to roadside, or in steep areas with convex slopes to avoid the use of intermediate supports. As a model for estimating the performance of the tethered skidder is not available, the purpose of this manuscript is to present a preliminary model. A methodology for a six-wheel drive tethered skidder is developed by extending existing non-tethered four-wheel drive skidder models for extraction uphill in steep terrain. The load that can be skidded is a function of skidder weight, soil strength, and tether tension. Tire inflation pressure is also an important variable. The energy intensity of tethered skidders is much higher than for cable logging due to the weight of the skidder. The lighter the skidder, the lower the power requirements and the lower the energy intensity.

Prediction of tractor drive tire slippage under different inflation pressures

The slippage of various sizes tractors under similar operating conditions can be compared based on the traction coefficient. However, a preliminary prediction of tractor drive tire slippage is problematic because the numerical expression of tire inflation pressure is not directly included in known mathematical models. The purpose of this study is to find a method for predicting the slippage of a tractor's driving tires, which includes a numerical expression of the tire inflation pressure. Based on the results of experimental studies of Case Farmall 115U MFWD tractor equipped with radial-ply tires, on wheat stubble on a loam soil, a method was developed to predict tire slippage based on the traction coefficient by estimating the tire inflation pressure. The obtained empirical equation allows to theoretical prediction of drive tire slippage in 4WD and 2WD modes, estimating the radial-ply tire inflation pressure in the range of 70–195 kPa.

Measuring Method of Slip Ratio for Tractor Driving Wheels Based on Machine Vision

Tractors are prone to large slips when they are in field operation. The degree of slip plays a vital role in traction efficiency and fuel efficiency. This paper presents a method for measuring the slip ratio of tractors in field operation based on machine vision. The accurate measurement of slip ratio needs to obtain actual velocity and theoretical velocity separately. For obtaining the actual velocity, a monocular camera mounted on the tractor vertically faces down at the ground to collect images. Then, the feature points of inter-frame ground images are matched by the ORB (Oriented FAST and Rotated BRIEF) algorithm for calculating the translational displacement. Next, a homography matrix based on camera calibration is proposed to complete the transformation of a point from the pixel coordinate system to the world coordinate system. Aiming to acquire the theoretical velocity, a method that takes the variations in tire radius into account is proposed, and the tire radii of the driving wheels are indirectly determined by the tire inflation pressure in real-time. The proposed measurement method was verified with an experimental tractor. The results show that the mean absolute errors of the tractor driving wheels’ slip ratio measured by the machine vision method are less than 0.75%, and the maximum of the absolute errors is not more than 2.22%, which shows good performance.

Instrumentation response of full-scale thin airfield pavements

ABSTRACT Instrumentation response data from full-scale accelerated pavement testing have been used to inform pavement design models and enhance service life predictions to ensure long-term operating conditions. However, some aircraft, i.e. military aircraft, may have a requirement to operate under relatively short-term conditions on airfields that are constructed below optimal conditions. Accordingly, the objective of this study was to construct, traffic, and collect instrumentation data from airfield pavement test sections constructed with asphalt thicknesses below existing military standards. Three asphalt thicknesses and two base course strengths were evaluated using two different aircraft simulators each at two tire inflation pressures. Earth pressure cells, single-depth deflectometers, and asphalt strain gauges were used to collect response data. Instrumentation response data were sensitive to increases in asphalt layer thickness, i.e. an increase in asphalt layer thickness generally resulted in an improvement in measured response albeit in relatively thin asphalt layers. Instrumentation response data were more sensitive to tire inflation pressure changes at higher loading conditions when compared to lower loading conditions. Finally, a layered elastic analysis using a non-uniform tire pressure distribution was found to provide a better approximation of measured earth pressure cell response than that of a typically assumed uniform pressure distribution.

Research on split and evolution of acoustic cavity resonance frequency of rotating loaded tire

The tire acoustic cavity resonance noise (TACRN) is known to contribute to audible noise in the passenger compartment of a vehicle. In order to reduce TACRN effectively, its mechanism needs to be grasped better. In this paper, the calculation formulas of tire acoustic cavity resonance frequency for four different conditions such as static unloaded tire, static loaded tire, rotating unloaded tire, and rotating loaded tire are analyzed and verified by the simulation and experiment. In particular, the resonance frequency formulas of static loaded tire introducing inflation pressure and rotating loaded tire are proposed and verified, respectively, in this paper. And the influence of tire inflation pressure, load, and running velocity on splitting frequency are studied. Some new findings are described and discussed; for example, the first-order resonance frequency may split into four resonance frequencies in most cases, and may split into three resonance frequencies in certain cases when a loaded tire is rotating. And the existing conditions for three and four resonance frequencies are also discussed.

Development Of Regression Models To Measure Energy And Inflation Time Of A Fabricated Tyre Pressure Control Unit

Tyre pressure plays a significant role in ensuring safe and economical driving. This research work was done in two major steps. A novel tyre pressure control unit was developed using mechatronic engineering approach of system integration for the control of car tyre inflation pressure. The control unit is designed to comprise air compressor, microcontroller, pressure sensor and rotary valves. A software program was written and embedded in the microcontroller which counts the number of pulses in the pressure sensor. The paper also goes further to illustrate an ordinary (non survival) linear regression models for the variations in energy and inflation time with inflation pressure. The results obtained showed that the values of energy and inflation time increased and varied for the tyre specimen considered. The developed statistical models help to predict required energy and inflation time at different inflation pressures.

Effect of tire slip losses on the energy demand and fuel consumption of a light-duty vehicle

The contribution of the tire-road slip of traction wheels to the total resistance opposing the motion of a light-duty commercial vehicle has been investigated through the simulation of several homologation and custom driving cycles. The calculation of the contribution of the tire slip losses was based on the estimation of the longitudinal tire slip, by means of Pacejka’s MF5.2 tire model. In this work, the computational steps required to evaluate this contribution were implemented in a previously developed fuel consumption simulation tool. Simulations were performed under several vehicle loading conditions and tire inflation pressures on traction and non-traction wheels, and considering different tire-road adherence conditions, in order to obtain a characterization of the tire slip losses over a wide range of working conditions. An analysis of the results shows that, although the contribution of tire slip losses to the total vehicle energy demand and fuel consumption may be relevant – especially under low-load, low adherence conditions – the sensitivity of the average on-cycle vehicle energy/fuel consumption to changes in the tire inflation pressure is only affected slightly by tire slip losses. Therefore, tire slip losses can be neglected in practice, when the aim of a simulation is to optimize the tire pressure to achieve average vehicle working conditions over a driving cycle.

A practical quantification of longitudinal slippage of robot platform wheels traversing on solid balls based uneven terrain

This research is spearhead for longitudinal slippage of robot platform wheels traversing on solid balls based uneven terrain. For this purpose, effects of solid ball diameter (0.0127–0.0508 m) accompanying with tire inflation pressure (20.68–55.16 kPa) and platform forward speed (0.17–0.50 m/s) on the slippage were practically quantified. Robotic experiments were executed in controlled test bed prepared by solid ceramic balls. Tentative data collected from the experiments indicate that the wheels experienced low (<30%), moderate (30–60%) and high slippage (>60%) under effects of independent variables. Results demonstrated that the increasing effect of the dominant variable of solid ball diameter on the slippage was 3.6 and 2.6 times greater than that of platform forward speed and tire inflation pressure, respectively. Meanwhile, the increasing linear effect of tire inflation pressure on the slippage was prevailed (1.4 times) than the decreasing linear effect of platform forward speed. Hence, to minimize the slippage as well as power loss of the platform traversing on each solid ball diameter, adjustment of tire inflation pressure should be enumerated as first priority. Overall, analytical results obtained in this research lead to open a new prospection for comprehending the slippage trends of off-road wheeled robots traversing on an uneven terrain composed of solid balls. Practicability of this type of the robots is remark in various industrial robotic operations, especially for process towers and reactors of oil, gas, petrochemical, and chemical industries. Hence, quantitative and qualitative information of this research are a rich source for relevant industrial investigators and experts who involved in this realm.

Parametric Study of Factors Affecting Lateral Stability of a Public Transportation Vehicle

The availability of public transport is one of the solutions to traffic congestion in Jakarta. Focusing on angkot, one of the public transport types in Jakarta, this study discusses a model and simulations to investigate several factors that affect its lateral stability. Those factors include rear tire inflation pressure, passenger configuration, velocity, and downhill inclination angle. The results show that the stability of an angkot is proportional to the rear tires cornering stiffness. It also has an indirect relationship with the passenger configuration within the angkot. Moreover, the stability of an angkot decreases as its velocity and the angle of the inclined road increase. In general, this study is expected to have a contribution to the development of public transport in Jakarta, especially angkot.