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Abstract In this article, a unique design for Hydro-Pneumatic Energy Harvesting Suspension HPEHS system is introduced. The design includes a hydraulic rectifier to maintain one-way flow direction in order to obtain maximum power generation from the vertical oscillation of the suspension system and achieve handling and comfort car drive. A mathematical model is presented to study the system dynamics and non-linear effects for HPEHS system. A simulation model is created by using Advanced Modeling Environment Simulations software (AMEsim) to analyze system performance. Furthermore, a co-simulation platform model is developed using Matlab-Simulink and AMEsim to optimize the PID controller parameters of the external variable load resistor applied on the generator by using Particle Swarm Optimization (PSO).

Electro-hydraulic actuated systems are widely used in industrial applications due to high torque density, higher speeds and wide bandwidth operation. However, the complexities and the parametric uncertainties of the hydraulic actuated systems pose challenges in establishing analytical mathematical models. Unlike electro-mechanical and pneumatic systems, the nonlinear dynamics due to dead band, hysteresis, nonlinear pressure flow relations, leakages and friction affects the pressure sensitivity and flow gain by altering the system's transient response, which can introduce asymmetric oscillatory behavior and a lag in the system response. The parametric uncertainties make it imperative to have condition monitoring with in-built diagnostics capability. Timely faults detection and isolation can help mitigate catastrophic failures. This paper presents a signal-based fault diagnostic scheme for a gearbox hydraulic actuator leakage detection using the wavelet transform.

Based on the traditional heavy commercial vehicle, hydraulic hub-motor drive vehicle (HHMDV) is equipped with a hydraulic hub-motor auxiliary drive system, which makes the vehicle change from the rear-wheel drive to the four-wheel drive to improve the traction performance on low-adhesion road. In the typical operating mode of the vehicle, the leakage of the hydraulic system increases because of the oil temperature rising, this makes the control precision of the hydraulic system drop. Therefore, a temperature compensation control strategy for the assist mode is proposed in this paper. According to the principle of flow continuity, considering the loss of the system and the expected wheel speed, the control strategy of multifactor target pump displacement based on temperature compensation is derived. The control strategy is verified by the co-simulation platform of MATLAB/Simulink and AMESim.

This document establishes the requirements for technical content and format of hydraulic system diagrams. This document does not establish configuration requirements, material, or performance requirements for any system or component identified herein. The purpose of this document is to specify the minimum technical content of marine and submergence vehicle hydraulic system diagrams and provide a standard format. Diagrams prepared in accordance with this document will be suitable for use in procurement activity, shipboard installation, and technical manuals for use in troubleshooting, operation, and maintenance of the hydraulic system.

This document establishes the requirements for technical content and format of hydraulic system diagrams. This document does not establish configuration requirements, material, or performance requirements for any system or component identified herein.

Although not limited to, these installations are normally used on trucks considered as Medium Duty (Class 6 and 7), as well as Heavy Duty (Class 8).

This document establishes standard graphical symbols and color conventions for use in either still (static) or animated graphics used for communicating service information. This document’s purpose is to communicate conventions for using those symbols and colors to accurately and consistently communicate intended information via graphics-based documentation. These practices are intended for use in service procedures, assembly instructions, training materials, and similar applications when trying to minimize the amount of human natural language text used within the document. The still and animated graphical conventions referenced should support effective communication via paper and “traditional” electronic media. The conventions can also extend to documenting via additional electronic delivery paradigms such as Augmented Reality (AR).

This document establishes standard graphical symbols and color conventions for use in either still (static) or animated graphics used for communicating service information. This document’s purpose is to communicate conventions for using those symbols and colors to accurately and consistently communicate intended information via graphics-based documentation. These practices are intended for use in service procedures, assembly instructions, training materials, and similar applications when trying to minimize the amount of human natural language text used within the document. The still and animated graphical conventions referenced should support effective communication via paper and “traditional” electronic media. The conventions can also extend to documenting via additional electronic delivery paradigms such as augmented reality (AR).

This document presents a catalog of safety sign text and artwork that can be used by any ready mixed concrete truck manufacturer to warn of common hazards.

This paper describes the preliminary results of a study focused on the semi empirical modeling of an excavator's hydraulic pump. From the viewpoint of designing and tuning an efficient control system, the excavator is a very complex nonlinear plant. To design and tune such a complex control system an extremely good nonlinear model of the plant is necessary. The problem of modeling an excavator is considered in this paper; a nonlinear mathematical model of an excavator has been developed using the bond graph methodology realized in the AMESim® simulation software to replicate actual operating conditions. The excavator model is described by two models: a hydraulic model and a kinematic model. At this stage of research the hydraulic model deals solely with the model of the main hydraulic pump, which has been conceived as a semi empirical model.

An experimental methodology is proposed to measure the rollover propensity of road tankers when subjected to lateral perturbations derived from steering manoeuvers. The testing principle involves subjecting a scaled down sprung tank to the elimination of a lateral acceleration, to analyze its rollover propensity as a function of various vehicle's operational and design parameters. Initial acceleration is generated through putting the scaled tank on a tilt table supported by a hydraulic piston. The controlled release of the fluid in the hydraulic system generates a perturbation situation for the tank, similar to the one that a vehicle experiences when leaving a curved section of the road and going to a straight segment. Durations for the maneuver and initial tilt angles characterize both the corresponding intensities of the steering maneuver.

Abstract A novel modeling method for the hydraulic hub motor drive system (HHMDS) is proposed to overcome the difficulty of using the complex AMESim model in the hardware-in-the-loop (HIL) test. The hydraulic pipeline model of the HHMDS is simplified by the lumped parameter approach. According to the node cavity method, a set of flow pressure differential equations is derived. These equations are used to describe the dynamic model of the HHMDS. To solve the rigidity problem of the model and improve the real-time performance of simulation, the HHMDS model is simplified with the integrated model and order reduction methods. Then, the simplified model is created through MATLAB/Simulink, and the accuracy of the modeling method is verified. In the three typical operating modes of the heavy commercial vehicle with HHMDS, the simulation results of the Simulink model and AMESim model are basically the same. At last, the model established by the Simulink is used in the HIL test.

Off highways vehicles especially tractors are prone to operate on fields where tractors are exposed to dry crops, chaffs (the husks of corn or other seed separated by winnowing or threshing) and particles which can catch fire easily when it is exposed to surface/skin temperature of more than 200 degree Celsius. It will be a basic projection that tractor will be having vertical exhaust tube at a height but there are certain tractors and applications where exhaust pipe must be below certain height, and which will be close to the ground. In these scenarios the skin temperature of exposed exhaust tail pipe part must be within a limit and that must be within the existing design. Break firing point of chaffs and husk also experimented at different moisture level. Several options are being verified on different heat flow and geometry changes, additional air entry jet nozzle with double pipe arrangement.

A slow-acting active control pneumatic suspension system for heavy truck applications is described. The first part of the paper discusses the control law strategy for an active pneumatic damping system concept. The second part descnies the application of the concept to a pneumatic sleeper bunk suspension system for on-highway trucks. The pneumatic suspension improves the quality of the sleeping environment for over-the-road truck drivers. Also, this concept has further application to a chassis suspension system to improve the truck's ride quality and handling characteristics.

Presenting a brand new approach to heat exchangers for engines, transmissions, hydraulic systems, etc. This new heat exchanger is made of only two pieces of circular extruded aluminum profiles: Core and shell. No soldering: The core and the shell is assembled by a minimum of automated work. In an oil to water cooling application, the active surface on the oil side of the core is enlarged by fins 0.2 mm thick, 0.3 mm spacing, and 3 mm high. The fins are made in unique production machines and enlarge the active surface area approximately five times compared to a conventional heat exchanger of the same dimensions. The principle utilizes the low pressure drop at laminar flow and avoids the disadvantage of low heat transfer after a certain laminar flow length. The result is approximately three times higher oil heat dissipation, combined with very low oil pressure drop, compared to conventional technique.

In response to the growing industry interest in environmentally acceptable (EA) lubricants, a hydraulic oil development program was initiated with these express objectives: Define the environmental impact and performance expectations for a lubricant used in applications where inadvertent leakage to the environment may occur. Develop a new product which degrades rapidly and is nontoxic to fish while providing satisfactory field performance in severe applications. This paper will first review the current regulatory initiatives and proposed ecotox test requirements for this class of lubricant. In addition, ecotox data for the candidate fluids will be presented along with recommendations aimed at more clearly defining the test requirements and limits. Lubricant performance data, including laboratory evaluation and field experience, for a vegetable-based hydraulic fluid will be presented, identifying both performance strengths and weaknesses.

Fixed displacement pumps will continue to be a popular choice for hydraulic system designers for decades to come. These pumps are used in almost every industrial and mobile market segment and are generally less expensive than comparable variable displacement type pumps. Fixed displacement “Vane Type” pumps are especially popular because of their low noise characteristics as well as their inherent repair features. The demand for “Vane Type” fixed displacement pumps continues to grow in all market segments. Because of this continued demand, a new design of “fixed displacement vane pumps” is being developed. These pumps, designated the VPF Series, are targeted to offer continuous operating pressures up to 280 BAR with displacements from 40 to 215 cc/rev.

A mathematical model of an axial piston pump with a flapper-nozzle valve was developed. The first stage was dynamically stable, and calculated values of first-stage gain and dynamic response agreed well with experimental values. Linearized relations were produced for each component part and were combined to form the total state-variable representation of the model. The open loop system, the combined axial piston pump and flapper-nozzle valve, exhibited dynamic instability. However, when the feedback loop was augmented by the output pressure differential, stability was achieved. From the time responses of the augmented optimal control system, we observed that an increase of input current had little effect on the system response. Doubling the discharge flow rate doubled the overshoot, and an increase in the discharge volume slowed down the system responses. Increasing rotational speed of the pump produced a higher overshoot and a slower response.

The direct interface of fluid power components to digital computers requires electrohydraulic devices which can be actuated by a digital signal. High speed solenoid valves are devices ideally suited for this kind of application due to their on/off characteristics. In the last two decades, considerable research has been focused on developing fast responding on/off valves and this research has achieved some success. The fastest responding valves that have been reported are usually single stage and can only handle low flow rates. Two stage valves which can accommodate high flow rates have been developed, but they are either slow in responding or complicated in construction. In this paper, the feasibility of a rotary based, single stage, fast responding digital valve is considered. The feasibility study consisted of developing a nonlinear model of the valve from which transient and steady state responses were simulated.

The problem of synchronizing several loads has been the subject of many studies over the past few years. Some of the authors have been involved in the design of high precision flow divider/combiner valves which are accurate to 99% over large pressure and flow ranges. The disadvantage of these designs lies in their inflexibility in terms of varying flow with complete independence to the various loads. Traditional approaches to the multi-load problem have been to use velocity or flow feedback signals to several electrohydraulic valves to obtain independent action. In this paper, the authors introduce the feasibility of using a single rotary type valve to provide a pulse width modulated flow pulse to each circuit. A model of the basic concept was used to establish the feasibility of the approach using simulation studies. A possible valve configuration to implement the concept is presented.