Reverse engineering and 3D scanning are critical tools for remanufacturing components in the context of the circular economy. By disassembling and measuring existing components, companies can design ...and develop new parts replacing the old ones, parts that are compatible with the original equipment, either to repair faulty subassemblies, or to improve efficiency or functionality. 3D scanning captures all information needed to reproduce components, allowing them to be created using additive manufacturing processes. Combining these technologies reduces waste by maximizing the use of existing products, and it reduces the amount of new raw materials and energy required for remanufacturing as well. The circular economy encourages companies to embrace a sustainable approach by considering the entire product lifecycle. Adopting these principles leads to a more environmentally friendly business model, avoids waste, reduces material consumption, and creates new revenue streams for remanufactured products. The current paper shows a way of adapting the principle of reverse engineering and a particular way of involving 3D scanning and 3D printing for the remanufacturing of hydraulic system components by using additive manufacturing. The use of 3D scanning is necessary in the reverse engineering process especially for components with complex geometry; in the present paper, the geometry of such a component is created.
High-pressure pumping units consisting of low-pressure pumping units and oscillating minibooster-type pressure intensifiers are an efficient solution for generating high pressure rates in hydraulic ...drive systems. Such pumping units are typically used in static applications (burst tests for pipelines and tanks) and mobile applications with high loads on small strokes of hydraulic cylinders (hydraulic tools and presses). Through experimental research, carried out on a test stand that can load a high-pressure hydraulic cylinder with heavy, high-magnitude loads, the authors demonstrated the possibility of expanding the range of technical applications of these pumping units to mobile applications with high loads over the entire stroke of hydraulic cylinders. A low-pressure pumping unit - 4 kW, 1500 rpm, 0...200 bar - was used; it was successively equipped with three types of miniboosters with different gain factors (I) (i=5.0; 1=6.6; and 1=7.6, respectively).
The application of a robot to rehabilitation has become a matter of great concern because of the requirement of functional recovery therapy of arm or limb. A novel pneumatic artificial muscle (PAM) ...actuator which has achieved increased popularity to provide the inherent safety and mobility assistance to humans performing tasks and another advantages such as high strength and power/weight ratio, low cost, compactness, ease of maintenance, cleanliness, readily available and cheap power source and so on. However, the complex nonlinear dynamics of the PAM manipulator makes it a challenging and appealing system for modeling and control design. The problems with the time variance, compliance, high hysteresis and nonlinearity of pneumatic systems have made it difficult to realize precise position control. In order to realize satisfactory control performance, the effect of nonlinear factors contained in the PAM manipulator must be considered.
The purpose of this study is to improve the control performance of 2 axes PAM manipulator using a nonlinear PID controller. Superb mixture of conventional PID controller and the neural network, which has powerful capability of learning, adaptation and tackling nonlinearity, brings us a novel nonlinear PID controller using neural network. This proposed controller is appropriate for a kind of plants with nonlinearity uncertainties and disturbances. The experiments were carried out in practical 2 axes PAM manipulator and the effectiveness of the proposed control algorithm was demonstrated through the experiments, which suggests its superior performance and disturbance rejection.
The emerging process of orbital drilling (OD) can greatly reduce or eliminate the defects associated with the drilling of composites; e.g., delamination, and thermal damage. The effects of the OD ...process parameters on the hole quality attributes were established in the form of machinability maps; an aspect that has not been reported before. The results showed significant enhancement in the hole quality compared to conventional drilling, due to the reduced axial force and cutting temperature, resulting from the redistribution of the load exerted by cutting edges and the cooling effect of the unstable rotational air flow in the tool-workpiece annular gap.
The article presents the findings of theoretical and experimental research on hydraulic processes occurring
in the hydraulic drives of transport machines. The paper analyses the influence of ...hydrodynamic processes on the flow characteristics
of fluid considering different hydraulic fitting connections. The performed analysis is based on numerical simulations using
Navier–Stokes equations for the velocity field. The dynamics of fluid flow in the hydraulic system has been investigated taking into
account the main parameters like system flow rate in the range of 5 to 100 L/min, the diameter of the pipeline making 1/2” and fitting
standards DKOL, ORFS, BSP and JIS. As a result, pressure drop, power losses, resistance and flow coefficients at different fitting
connections have been obtained. The article compares the provided results with the findings given employing the calculation method
for the standard of equivalent length fitting. To simulate fluid flow, a mesh independence study and turbulence calculations have been
performed. Simulation results have been examined conducting physical experiments on measuring pressure losses. Each experimental research
includes three measurements of connections bearing in mind each fitting standard.
In this paper, an automated umbilical system based on a 6-dof (degree of freedom) hydraulic parallel mechanism is proposed to automate the rocket propellant loading process. The mechanical structure, ...vision acquisition algorithm, and control algorithm used in the system are described in detail in the paper. To address the fluid nonlinearity problem of the hydraulic drive system, nonlinear compensation and three-state feedback control are used in the paper to enhance the performance of the hydraulic system. For the problem of force tracking during the docking process between the umbilical system and the rocket, an adaptive impedance control algorithm based on the online environmental parameter estimation is proposed in the paper, which effectively reduces the contact force during the docking process. The dynamic tracking and docking experiments indicate that this automated umbilical system features rapid reaction speed, high measurement precision, and good flexibility, which can be used to realize the auto-mating and following task for the propellant loading robot in a hazardous environment.
In order to meet the working performance of large plant protection machine and according to the actual working requirements, this paper proposes a design of hydrostatic chassis drive system for a ...large plant protection machine. The purpose of this study is to realize the anti-slip rotation function of the plant protection machine and improve the driving stability through the combination of a hydraulic drive system and shunt valve. In this study, a closed circuit with a single pump and four motors is used, and a diverter valve is used to prevent the wheels from skidding during the driving of the plant protection machine. The parameters of the main hydraulic components of the hydraulic drive system were firstly calculated and selected; then the AMESim software was used to model and simulate the hydraulic drive system. Finally, a test platform with anti-skid function is designed and built, and the test results are as follows: when the diverter valve is closed, the plant protection machine drives at 3 km/h and 6 km/h respectively, and the skid rate is 3.79% and 6.17%; when the diverter valve is open, the plant protection machine drives at 3 km/h and 6 km/h respectively, and the skid rate is 1.33% and 2.70% respectively. The test results show that the hydraulic chassis of the plant protection machine designed in this study has good driving stability and can effectively reduce the slip rate of the plant protection machine in the process of driving in the field, which provides an effective theoretical support for the design of the driving system of the hydraulic chassis of the plant protection machine.
This reprint focuses on the recent advances in fluid power technology reporting results in a wide range of applications. Studies concerning the developments of pumps both at constant and variable ...displacement are reported. Analyses are focused on the improvement of efficiency, control, design and pressure ripple reduction. About fluid power, several applications are investigated with the aim of reducing energy losses, in particular implementations in an excavator, a hybrid transmission and a system for agricultural solutions are described. Applications are studied focusing also on the effects of a particular load holding valve, and facing the relevant aspects of the condition monitoring, failure modes and effects analysis. The fluid power covers a very wide range of application as demonstrated by the paper concerning an exoskeleton device. Finally, a particular application concerning a gas pressure regulator with lower noise emission is reported.
For some time, there has been talk about the fourth industrial revolution, and although it is in progress, specialists are adding new meanings to it every day. The new meanings are mainly related to ...computer science, sensorics, automation, but especially to the use of the Internet. In these days when humanity is brutally hit by the coronavirus pandemic, one of the problems is lack of adequate managerial capacity in coordinating and especially in maintaining manufacturing at an acceptable level when most workers and specialists stay home, participating in current activities through the telephone and the computer. In the field of hydraulic drives, many of the requirements of Industry 4.0 are achieved industrially, usually on technological areas, but with high chances of rapid transition across the entire manufacturing.
The working fluid temperature in the hydrostatic support system of the metal working machine plate is determined as a function of the drive operation time under different operating conditions. ...Temperature deformations of parts, units and assemblies of metal cutting machines are greatly influenced by the temperature of hydraulic drive working fluid, so the issues of optimization of working fluid temperature are given more attention. Experimental studies of the operating fluid temperature of the hydraulic support system of the faceplate and parameters affecting its changes were carried out under conditions close to operational conditions. Parts of different mass (0.5-3.8 t) were processed at different speeds of plate rotation.
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