Equations of state that govern the process of new products launched in the market are a generalization of the Nerlowe Arrow equations [2]. The existence of four independent parameters regulating the behavior enable th...
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ISBN:
(纸本)9789048196883
Equations of state that govern the process of new products launched in the market are a generalization of the Nerlowe Arrow equations [2]. The existence of four independent parameters regulating the behavior enable the release process of finding sufficient conditions for determining an optimal trajectory using a single command. Maximizing Hamiltonian corresponding dynamic system results two control functions which can be independently or simultaneously used. In this paper we demonstrate the possibility of using two independent commands, thus obtaining two minimum times, to get a higher test time optimization of data release in the initial and final conditions taking the smaller of the two minimum times corresponding to the two control functions.
The paper presents theoretical aspects of the calculus and simulation of transportation effect of vibratory hoppers. Two mathematical models are developed, based on distinct mechanical assumptions, which describe the ...
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ISBN:
(纸本)9789048196883
The paper presents theoretical aspects of the calculus and simulation of transportation effect of vibratory hoppers. Two mathematical models are developed, based on distinct mechanical assumptions, which describe the motion of a singular small part, assimilated with a material particle, on the vibratory track. The small part executes a complex motion, composed by slides and jumps, and follows the conical-helix shape of the track.
This article describes a two-dimensional model for the analysis of the transmission error and dynamic performance of a spur gear transmission supported by bearings including defects. Knowing the position of each wheel...
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ISBN:
(纸本)9789048196883
This article describes a two-dimensional model for the analysis of the transmission error and dynamic performance of a spur gear transmission supported by bearings including defects. Knowing the position of each wheel and profiles geometry, including errors and roundings, contact points are determined. Meshing forces and associated deformations are then calculated, simplifying the deformation computation by means of its subdivision in structural and local deformations. The application of this procedure improves the results and reduces the computational effort. The model supports the possibility of contact on both flanks of the teeth simultaneously and it also takes into account the variable number of bearing elements. Finally, an application example of this method is presented, highlighting the effect of cracks, surface defects and tooth gear profile errors on the transmission error.
We consider the geometry of four spatial displacements, arranged in cyclic order, such that the relative motion between neighbouring displacements is a pure rotation. We compute the locus of points whose homologous im...
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ISBN:
(纸本)9789048196883
We consider the geometry of four spatial displacements, arranged in cyclic order, such that the relative motion between neighbouring displacements is a pure rotation. We compute the locus of points whose homologous images lie on a circle, the locus of oriented planes whose homologous images are tangent to a cone of revolution, and the locus of oriented lines whose homologous images form a skew quadrilateral on a hyperboloid of revolution.
The work analyses the results of measurements for vibrations made for the system hand arm and their comparison to the mechanical theoretical model. The theoretical results have been obtained by the integration of the ...
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ISBN:
(纸本)9789048196883
The work analyses the results of measurements for vibrations made for the system hand arm and their comparison to the mechanical theoretical model. The theoretical results have been obtained by the integration of the system of equations corresponding to the hand-arm system. The integration of the equations has been done taking into account the signal at the entrance in the system (forced excitation) coming from the machine-tool. In these conditions were measured the displacements due to vibrations;vibrations produced during a mechanical process on the machine tool (cutting process) and then it was analyzed how they are transmitted through the hand-arm system up to the organism. The signal of entrance in the system was applied to the hand and fingers and the measurements were done for several standard rotation of the machine-tool, the exciting source (lathe).
The paper presents research on modeling the influence of an azimuth tracking linkage on the energetic response of a low CPV system build up of a PV module and two mirrors: one on the left side and symmetrically on the...
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ISBN:
(纸本)9789048196883
The paper presents research on modeling the influence of an azimuth tracking linkage on the energetic response of a low CPV system build up of a PV module and two mirrors: one on the left side and symmetrically on the right side along the length of the PV module. This paper analyses the influence of the azimuth open tracking linkage, its tracking accuracy and the mirror-PV relative geometry on the tracking efficiency and on the size of a low CPV system with mirrors. This analysis has two main objectives: maximizing the tracking efficiency of the direct solar radiation and minimizing the overall size of the CPV system. The geometric modeling of this CPV system and the numerical simulations allow the identification of the optimal solutions.
Most walking machines cannot operate within the typical natural environment, including ground relief especially. In that case, the main tasks are adaptive gait control realization and perceptual computing system devel...
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ISBN:
(纸本)9789048196883
Most walking machines cannot operate within the typical natural environment, including ground relief especially. In that case, the main tasks are adaptive gait control realization and perceptual computing system developing. There are no paths to solve this problem without new experimental exploration of animals' gaits. Usage of high speed strobelight photography made its possible to observe some hidden aspects of horse gait and leg control processes, like definition of hoof stepping point location.
In this paper we present the human lower limb inverse dynamic analysis in the sight of some useful dynamic parameters determination for orthopedic implants design. We elaborate the human lower limb mathematic model ba...
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ISBN:
(纸本)9789048196883
In this paper we present the human lower limb inverse dynamic analysis in the sight of some useful dynamic parameters determination for orthopedic implants design. We elaborate the human lower limb mathematic model based on some cinematic and dynamic considerations obtained on experimental and analytical way. The inverse dynamic analysis has on its base the Newton Euler formalism completed with Lagrange's multipliers method. Through this analysis we obtain the connection forces which appear at the human lower limb's joints level for walking activity. With these results we will study through finite element method an orthopedic implant which will partially replace the human lower limb's ankle joint.
The paper attempts to give a contribution about the mechanical and thermal behavior of fluidic muscles, through theoretical modeling and experimental tests. Fluidic muscles are innovative mechanical components particu...
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ISBN:
(纸本)9789048196883
The paper attempts to give a contribution about the mechanical and thermal behavior of fluidic muscles, through theoretical modeling and experimental tests. Fluidic muscles are innovative mechanical components particularly attractive for their flexibility and performances. In particular, braided pneumatic muscle actuators are a very significant development of the pneumatics, being able to operate in a wide range of environments and applied in a wide spectrum of industrial and non-industrial applications, providing a good control of force and position and showing excellent power/weight performances. But, on the contrary of conventional pneumatic actuators, artificial muscles operate under significant thermal gradients. Internal temperature distribution is conditioned by the size and is strictly related to the actual mechanical performances. Integrated mechanical and experimental testing implemented on an original test bench and are focused and discussed.
Cable-drum systems are utilized to convert the rotary motion of a drum into a translational motion of a linear stage connected to the cable. These systems are preferred where low backlash and high stiffness is expecte...
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ISBN:
(纸本)9789048196883
Cable-drum systems are utilized to convert the rotary motion of a drum into a translational motion of a linear stage connected to the cable. These systems are preferred where low backlash and high stiffness is expected. They are commonly employed in machines like elevators, photocopy machines, printers, plotters etc. For machines having long working ranges, cable-drum systems employing a high resolution encoder offers a practical low cost alternative in position sensing. In most traditional machines and equipments, to get linear position information;potentiometers, linear encoders, laser range finders etc. are commonly used. However, these alternatives are expensive and their installation is not straight forward. Cable-drum systems are not problem free either. The problem coming from using cable-drum system as a linear position sensor grows out of dynamic friction. In this study, the change in the dynamic friction coefficient of the cable drum system is modeled by using Euler and LuGre friction approaches. In order to see the change of the friction values, the developed model is simulated. To verify of the theoretical results, an experimental set-up is constructed. Both results are presented. It is concluded that for better positioning control change in dynamic friction coefficient during the motion should be accounted for.
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