Methodology for choosing a propulsion device for special-purpose vehicles

The ability to move on different types of soils is one of the main indicators of the efficiency of mobile vehicles in off-road conditions. The movement of such special mobile machines is carried out due to the interaction of the propulsion with the support surface. Therefore, significant reserves to increase productivity and reduce the cost of technological and transport works are laid in reducing energy consumption when the engine interacts with the surface. On the process of interaction of the wheel drive with the deformable support surface it is established that the parameters of this interaction depend on a number of factors: normal load, angular velocity and torque. In the General case, the parameters of interaction of each engine change when changing the mode of movement of the wheeled vehicle, and the ability to change the air pressure in the tires when driving on different support surfaces allows to increase the performance of the wheeled vehicle In the study of the caterpillar, it was found that the pitch of the caterpillar, the stiffness of the caterpillar, the angular stiffness of two adjacent tracks, reducing the pitch of the caterpillar chain, reducing the stiffness of the caterpillar, increasing the angular stiffness of two adjacent tracks, affect the efficiency of the machine. The scientific novelty of the study is to develop a method of choosing the engine of a special mobile machine that works off-road, in the process of its design. Wheel or crawler solutions will mainly determine the performance and efficiency of special purpose vehicles. The choice of engine for special mobile machines is based on a set of criteria. The criteria determine the importance of the implementation of the tasks in relation to the efficiency of functioning. Knowing the sowing capacity of the soil, and taking into account the possibility of movement of a particular special mobile machine depending on the type of soil, you can choose one or another type of engine.

Pengembangan Penataan Perparkiran Universitas Hasanuddin Di Fakultas Teknik, Fakultas MIPA Dan Fakultas Farmasi

Meningkatnya pemilikan kendaraan bermotor civitas akademika Universitas Hasanuddin mengakibatkan peningkatan permintaan fasilitas parkir mengingat fasilitas parkir merupakan bagian yang tak terpisahkan dari sistem transportasi sehingga menimbulkan kesemrawutan perparkiran seperti yang dilihat pada area perparkiran Fakultas Teknik, Fakultas MIPA dan Fakultas Farmasi. Tujuan penelitian ini, yaitu menyusun konsep penataan ruang parkir yang dapat menjelaskan kapasitas ruang parkir efektif ditinjau berdasarkan tata layout bangunan dan kebutuhan parkir Fakultas Teknik, Fakultas MIPA, dan Fakultas Farmasi di Universitas Hasanuddin Tamalanrea, Makassar menggunakan metode penelitian deskriptif kuantitatif dalam menganalisis karakteristik parkir untuk mengetahui kapasitas parkir, volume parkir, akumulasi parkir, tingkat penggunaan parkir, dan kebutuhan parkir kendaraan roda dua dan roda empat yang keluar-masuk area parkir selama lima hari kerja mulai pukul 06.30 sampai dengan pukul 17.30 dengan hasil penelitian menunjukkan bahwa penyusunan sebuah konsep penataan ruang parkir efektif di lingkungan tiga fakultas di Universitas Hasanuddin (Teknik, MIPA, dan Farmasi) berhasil disusun dengan merekomendasikan penggabungan beberapa lahan parkir menjadi satu area parkir kendaraan roda empat dan sentralisasi parkiran kendaraan beroda dua. The increasing number of vehicles ownership among the Hasanuddin University academic community resulted in increased demand for parking facilities; considering it is an integral part of the transportation system, the steep demands causing parking disorganize as seen in the parking facilities of the Faculty of Engineering, Faculty of Science and Faculty of Pharmacy. This study attempts to propose a parking spaces rearrangement that could describe the effective capacity of parking area from the standpoint of the building layout planning and the parking spaces needs of the Faculty of Engineering, Faculty of Science and Faculty of Pharmacy at the University of Hasanuddin Tamalanrea Makassar. Using descriptive quantitative research method in analyzing the characteristics of parking to determine the capacity of parking, parking volume, accumulated parking, parking usage levels, and the need for parking of the two-wheeled and four-wheeled vehicles entered and exited the parking area for five working days; starting at 06:30 AM until 17.30 PM, resulting a concept of an effective parking spaces rearrangement that encompassing the three faculty of Hasanuddin University (faculty of Engineering, Sciences, and Pharmacy) by recommending the incorporation of several of the parking lot into a four-wheeled vehicle parking areas and centralized parking facilities for two-wheeled vehicles.

Optimal Design of the Six-Wheel Steering System with Multiple Steering Modes

Vehicles will face different working conditions during the use, and different working conditions have different requirements for vehicle functions, which results in many subdivided models. An off-road vehicle is a subdivision model produced to adapt to complex road conditions. In order to adapt to complex road conditions, vehicles should have a good passing ability, small size, and good flexibility. The six-wheeled vehicle has both good passing ability and small volume, which is the best choice for off-road vehicles. The design of the steering system becomes the key step to improve the flexibility of the six-wheeled vehicle. This paper mainly designs an independent steering system for a six-wheel electric vehicle with higher flexibility. The system is designed for six-wheel electric vehicles driven by six in-wheel motors. It mainly includes mechanical steering system and electronic control steering system. Both mechanical steering systems and electronic control steering system have multiple steering modes. Firstly, this paper introduces the various steering modes of the mechanical steering system and the electronic control steering system. Secondly, a CAD model is established by using the software Solidworks, and the system structure is introduced in detail combined with the CAD model. Finally, a kinematics model is established and calculated. The calculation results showed that the steering system can significantly improve the flexibility of the vehicle, so that the vehicle can complete the steering stably and quickly on complex road sections.

Fuel Consumption of Wheeled Vehicle and Transportation Costs during Highway Construction/Reconstruction

A method is proposed for determining the fuel consumption of a wheeled vehicle depending on its speed, road surface flatness and road slope in the longitudinal direction. The purpose of the research is to derive mathematical relationships for calculating the fuel consumption of vehicles, which is one of the transport cost factors during the construction/reconstruction or overhaul of a highway. The proposed polynomial dependencies for calculating fuel in addition to vehicle speed, road surface flatness and its longitudinal slope take into account the mass-dimensional parameters of vehicles involved in road traffic. New mathematical relationships between the speed of wheeled vehicles, road surface flatness and longitudinal road slope allow to simulate the change in the value of fuel consumption of a wheeled vehicle when the speed of traffic flow or the slope of the road surface changes in the forward or reverse direction of the vehicle. In a graphic way, the influence of the pavement slope on the value of fuel consumption, both loaded and unloaded wheeled vehicle is presented. When determining transport costs associated with the highway construction, reconstruction or overhaul it is proposed to use empirical mathematical relationships, which make it possible to obtain fuel consumption with an accuracy of 5 % and save up to 15 % of budget (private) investments. The analysis of scientific publications of the existing approach determine the transport costs associated with highway construction, reconstruction or overhaul. The presented method for determining the fuel consumption of wheeled vehicles with small and large loading capacity increases the accuracy of determining transportation costs and reduces the level of financial costs for highway construction, reconstruction or overhaul.

Development of a simulation model of the heating process in the passenger cabin of a vehicle under low temperature conditions

Introduction. A distinctive feature of working conditions in the Arctic territories is the long period of exposure to low temperatures. Passenger transportation by road is becoming one of the key aspects of ensuring the continuity of the production process. The task of delivering workers to the place of work, moving them between work zones during a work shift is solved by using wheeled vehicles of various categories. One of the most widespread types of wheeled vehicles used to transport workers is the M3 category wheeled vehicles with a capacity of no more than 22 passengers. Ensuring the thermal comfort of vehicle passengers seems to be relevant, since ensuring biophysical compatibility minimizes the risks of cold injury by workers and maintains a high level of performance.Materials and methods. The results of the analysis of the Russian and foreign studies in the direction of ensuring thermal comfort and ensuring biophysical compatibility in confined spaces are presented. The results of computer modelling of the dynamics of microclimate parameters in the passenger cabin of a wheeled vehicle of M3 category with a capacity of no more than 22 passengers are presented.Results. The paper presents the results of theoretical studies, microclimate parameters in the passenger compartment of vehicles, taking into account the breathing of passengers and changes in the gas composition of exhaled air. Theoretical studies of the operation of the heating system of the passenger compartment were carried out, taking into account the refined breathing model of passengers. Distributions of microclimate parameters in the section of the passengercompartment were obtained when using a heating system with one heater; the impact of passengers’ breathing on the parameters of the microclimate in the passenger compartment was assessed.Discussion and conclusion. Based on the numerical solution of the system of heat transfer equations, directions for further research and recommendations are formulated to ensure thermal comfort in the passenger compartment of a wheeled vehicle at low temperatures. The materials of the work may be of interest to specialists involved in the design and ergonomics of wheeled vehicles, labor protection.

Tactics for using a Mobile Robot to Recover an Overturned wheeled Vehicle

This paper describes mobile robot tactics for recovering a wheeled vehicle that has overturned. If such a vehicle were to tip over backward off its wheels and become unable to recover itself, especially in areas where it would be difficult for humans to enter and work, total working efficiency could decline significantly, not only because the vehicle is no only able to perform its job, but because it becomes an obstacle to other work. Herein, we propose a robot-based recovery method that can be used to recover such overturned vehicles and demonstrates its utility. The recovery robot, which uses a mounted manipulator and hand to recover the overturned vehicle, is also equipped with a camera and a personal computer (PC). The ARToolKit software package installed on the robot-mounted PC detects ARmarkers attached to the overturned vehicle and uses the information they provide to orient itself in order to perform recovery operations. To facilitate these ARToolKit-based operations, it is necessary to conduct a theoretical analysis to clarify the distance between the robot manipulator and vehicle, and thus achieve an objective position for grasping the overturned vehicle. The experimental results obtained in this study demonstrate the effectiveness of our proposed system.

An observation algorithm for key motion states of skid-steered wheeled unmanned vehicle

With the increasing demand of military and civilian in the intelligent vehicles, the skid-steering theory has been widely used in unmanned ground vehicles, especially in unmanned military vehicles and unmanned surveillance platforms. Due to its driving environment complex and variable, which requires stricter dynamic control system. In order to improve the active safety performance of the skid-steering unmanned vehicle and develop the key technologies such as behavior decision planning technology, path tracking, and dynamic control technology, it is necessary to develop the dynamic state parameter observation system based on skid-steering theory. In this paper, an observation using Strong Track External Kalman Filter theory with noise matrix adaptive is designed to estimate vehicle kinematic parameters based on a 6 × 6 skid-steered unmanned vehicle. First, kinematic and dynamic model is built to analyze the characters of a skid-steered wheeled vehicle. Then a tire force estimation method based on dynamic model is presented to observe the tire longitude and vertical force. The tire force data is also used by Dugoff nonlinear model. Then an External Kalman Filter theory is designed to estimate vehicle kinematic parameters. To increase the accuracy and the robustness of the observer, the Strong Tracking EKF (STEKF) and noise adaptive adjustment is designed. Finally, a combined simulation using TruckSim and Simulink and the experiment using a 6 × 6 skid-steered unmanned vehicle verifies the efficiency of the observer. Results show that the observer is able to estimate the skid-steered wheeled vehicle states, and it also shows that the yaw rate result in the slip angle difference between each tire.

Investigations on the Stability of a Two-Wheeled Vehicle with a Tendency to Topple Sideways

Two-wheeled vehicles are the most commonly used means of transportation. Every day many unspoken tragedies are happening on the roads that kill the hope of many families. The primary cause of this is the inherent instability of the two-wheeled vehicle. In this paper, the precession effect of the gyroscope is used to prevent the sideway toppling of the bicycle. When the bicycle begins to tilt, the torque created by the gyroscope’s precession effect is applied to the gimbal, and the ensuing reaction moment keeps the bicycle upright. The movements of a bicycle with a gimbal placed on the bottom are measured, and a three-dimensional model with a sliding mode controller is created and simulated.

A novel nonlinear controller for enhancement of the transient dynamics performance of a three-wheeled vehicle during different conditions

In this study, a new controller to prevent the yaw instability and rollover of a three-wheeled vehicle has been proposed. This controller offers the most obvious opportunity for affecting the vehicle's lateral dynamics performance on the full range of nonlinearities during various operating boundaries. The active combined controller has been designed based on sliding mode control method using an active roll system and an active braking system to dominate the uncertainties of the nonlinear dynamic model. Firstly, to avoid rollover of the three-wheeled vehicle, the roll angle was considered as the control objective, and the anti-roll bar was employed as an actuator to produce the roll moment. Secondly, to increase the maneuverability and lateral dynamics enhancement, an active braking system was designed. In the control system, the yaw rate and the lateral velocity were regarded as the control variables to track their references. Moreover, to verify the performance of the mentioned combined controller, another control system has been designed using the linearization feedback control method. Then, computer simulation has been carried out with a 12 degrees of freedom dynamic model of the three-wheeled vehicle called the delta. Furthermore, a nonlinear tire model has been utilized to compute the longitudinal and the lateral forces. Next, the comparative simulation results confirmed the effectiveness of the robust control system to raise the vehicle's maneuverability and its rollover stability in comparison with the linearization feedback control method, especially when the three-wheeled vehicle is subjected to critical conditions.