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The purpose of this paper is to realize the lightweight of connecting rod and meet the requirements of low energy consumption and vibration. Based on the structural design of the original connecting rod, the finite element analysis was conducted to reduce the weight and increase the natural frequencies, so as to reduce materials consumption and improve the energy efficiency of internal combustion engine.

The finite element analysis, structural optimization design and topology optimization of the connecting rod are applied. Efficient hybrid method is deployed: static and modal analysis; and structure re-design of the connecting rod based on topology optimization.

After the optimization of the connecting rod, the weight is reduced from 1.7907 to 1.4875 kg, with a reduction of 16.93%. The maximum equivalent stress of the optimized connecting rod is 183.97 MPa and that of the original structure is 217.18 MPa, with the reduction of 15.62%. The first, second and third natural frequencies of the optimized connecting rod are increased by 8.89%, 8.85% and 11.09%, respectively. Through the finite element analysis and based on the lightweight, the maximum equivalent stress is reduced and the low-order natural frequency is increased.

This paper presents an optimization method on the connecting rod structure. Based on the statics and modal analysis of the connecting rod and combined with the topology optimization, the size of the connecting rod is improved, and the static and dynamic characteristics of the optimized connecting rod are improved.

THE Avery Connecting Rod Prover is designed for the balancing of both ends of a connecting rod simultaneously, the results being then compared with a standard rod previously tested. The standard rod is placed in the machine and balanced off by moving the poise weights until the automatic indicators remain at zero.

A new method of three‐dimensional remeshing is proposed for thermo‐viscoplastic finite element analysis of connecting rod forging. In the method, the deformed body to be remeshed is divided into a surface‐adaptive layer (SAL) and a core region. At the surface layer of hexahedral elements, the arrangement of nodal points is made by normal projection of boundary nodes in order to retard the mesh degeneracy, since the arrangement of boundary nodes can be easily achieved by using the information of the die surface patch. After generating the mesh automatically at the surface‐adaptive layer, the core region is automatically meshed by introducing a body‐fitted mapping technique. In order to show the effectiveness of the method in the three‐dimensional problem, forging of a connecting rod has been simulated as a practical example. The complete simulation of connecting rod forging has been carried out by using the thermo‐viscoplastic finite element method and the remeshing scheme. The analysis of transient heat transfer has been carried out for the workpiece by the finite element method, while the boundary element method has been used for the die.

A flap comprises three or more pivotally inter‐connected spanwise strips forming an articulated unit pivotally attached along one edge 42 to the wing 1, the flap being raised or lowered by a series of radius rods 15, 16, 17, 18 actuated by a hydraulic jack 6, 7. The rod 6 of the jack carries a cross‐piece 9 to which rods 10, 11, 12, 13 arc attached. The rod 10 carries a member 31 to which the lower end of the radius rod 15 is pivoted, while the rods 11, 12, 13 carry further members 32, 33, 34 which successively engage blocks 24, 25, 26, to which the rods 16, 17, 18 are pivoted, when the hydraulic jack is extended. Projections at the upper ends of the members 31, 32, 33, 34 engage the rear faces of the radius rods when the flap is fully raised, FIG. 5. Manually operated rack and pinion, or screw drive, may be substituted for the hydraulic jack.

The purpose of this paper is to apply a computer-aided engineering approach in order to improve the performance and the reliability of an innovative internal combustion engine. The engine is called twin engine packs system and it consists into the presence of two independent piston engines working in the same crankcase, thus allowing the helicopter to meet the safety standards of the fail-safe design approach, as happens with the twin-turbine helicopters, but with reduced operative costs. The goal is to propose to the designers modifications aimed to improve the performance of the components.

The crankshaft, connecting rod and the piston of the engine have been investigated by means of numerical FE models. Numerical fatigue assessments have been performed along with vibrational modes and buckling analysis in order to verify the structural integrity of the system.

On the basis of the numerical results, some modifications have been proposed to the designers and the originally proposed geometry has been modified. Eventually, the mass of the engine has been reduced keeping a high reliability level.

The prototype of the engine has been built following the modifications proposed in this paper. This paper represents a comprehensive application of a CAE methodology to a real industrial application.

This paper shows a complete CAE procedure applied to a real working engine whose performances and reliability have been improved by following the findings of this paper.

The purpose of this study is to establish an assembly accuracy analysis model of deployable arms based on Jacobian–Torsor theory to improve the assembly accuracy. Spacecraft deployable arm is one of the core components of spacecraft. Reducing the errors in assembly process is the main method to improve the assembly accuracy of spacecraft deployable arms.

First, the influence of composite connecting rod, root joint and arm joint on assembly accuracy in the tandem assembly process is analyzed to propose the assembly accuracy analysis model. Second, a non-tandem assembly process of “two joints fixed-composite rod installed-flange gasket compensated” is proposed and analyzed to improve the assembly accuracy of deployable arms. Finally, the feasibility of non-tandem assembly process strategy is verified by assembly experiment.

The experiential results show that the assembly errors are reduced compared with the tandem assembly process. The errors on axes x, y and z directions decreased from 14.1009 mm, 14.2424 mm and 0.8414 mm to 0.922 mm, 0.671 mm and 0.2393 mm, respectively. The errors round axes x and y directions also decreased from 0.0050° and 0.0053° to 0.00292° and 0.00251°, respectively.

This paper presents an assembly accuracy analysis model of deployable arms and applies the model to calculate assembly errors in tandem assembly process. In addition, a non-tandem assembly process is proposed based on the model. The experimental results show that the non-tandem assembly process can improve the assembly accuracy of deployable arms.

Since the outbreak of war, a number of enemy aircraft have fallen into German hands, either shot down, forced to land, or captured in occupied territory. Thus, in addition to the aircraft, their armament and equipment, various types of engines of the enemy Powers—English, French and American — have become available for examination. Research on the materials has been carried out on behalf of the Reich Air Ministry by various German engine builders, and makers of components, and by the D.V.L.—the German Aeronautical Research Institute. The present report summarizes the principal results of this research; in view of the magnitude of the collected material, only the more important features of the engines will be dealt with.

In hydraulically‐operated retractable wheels for aircraft the actuating member comprises a jack having a piston connected on one side with a motive pump and an exhaust, and on the other side with a hydro‐pneumatic pressure accumulator into which the liquid is forced by the jack during each lifting operation, the stored energy in the accumulator actuating the jack to assist the action of gravity when lowering the wheels. The retractable wheels R (Fig. 1) are each pivoted at A and connected to a fluid‐operated piston in a cylinder V pivoted at T, the wheels being drawn up into the machine through spring‐operated doors C1, D1 which are opened by fluid‐operated means G2 (Fig. 2) when the wheels are lowered. The cylinder V is connected by pipe 3 and non‐return valve 4 to a pump 1 supplied from a reservoir 2, surplus liquid being bye‐passed from the pump through a pipe 16. A pipe 5 for exhausting the cylinder V is connected through a manually‐operated valve 6 to the reservoir 5 and a branch 3a from the pipe 3 is connected to a cylinder 8 whereby pressure is applied to move valve 12 and non‐return valve 10 to place the other end of the cylinder V to discharge through pipes 3b, 3e to a pneumatic accumulator 9 supplied with air from a cylinder 14. When pressure is supplied by the pump 1 to the cylinder V to retract the wheels, a projection on the valve 12 opens the valve 10 and the liquid in the other end of the cylinder is forced into the accumulator 9, and when the wheels are to be lowered the valve 6 is opened by the lever 7 to exhaust one end of the cylinder into the reservoir 2 while the other end of the cylinder is supplied with pressure fluid from the accumulator. A pipe 17 from the pump 1 is connected to a cylinder G2 and is provided with a branch 18 and manually‐operated valve 19 whereby the cylinder may be exhausted. The cylinders G2 (Fig. 5) are connected by links to the doors C1, C2 maintained in the closed position by springs r1, r2, the doors C1, C2 being interconnected to open smaller doors D1 (Fig. 1) which remain open when the wheels R are lowered. The levers 25, 20, 7 (Fig. 2) are connected to a single control lever. In Fig. 10, the wheel arm J is pivoted at A and is connected by piston rod P to the cylinder V pivoted at T. A wire 35 connected to the arm J passes over pulleys 36, 37, and is connected to a piston in a horizontal cylinder 41 open to a pneumatic reservoir 9. When the wheel R is raised to the position R1 by the admission of fluid under the piston P, the wire 35 rapidly withdraws the piston in the cylinder 41 to compress the air in the accumulator 9, and since the effect of gravity is not so pronounced between the positions R, R1 as between R1, R2 and the fact that the air pressure on R tends to raise the wheel, the pressure applied to the piston P is mainly stored in the accumulator 9. From the position R to R1 the effect of air pressure is less and gravity greater, so that between these positions the wire 35 is adapted to lap around a pulley 43 on the axis A whereby the movement of the piston in the cylinder 41 is small and less power is stored in the accumulator 9, the pressure on the piston P being primarily expended in raising the wheel from R1 to R2. Similarly when lowering the wheel the accumulator expends the greatest power between R1, R. A device for recovering any leakage from the pump 1 when the reservoir 2 is at a higher level is shown in Fig. 9. A leakage pipe 28 is connected by a housing 29 and pipe 30 to the suction pipe 33, and the housing contains a float 31 with upper and lower needle valves. When the housing 29 is full of liquid, the pipe 28 is closed by the upper needle valve and the liquid in the housing is withdrawn through pipe 30 and when the housing is empty the float falls and closes the pipe 30.

Underactuated fingers are adapted to generate several grasping modes for different tasks, and coupled fingers and self-adaptive fingers are two important types of them. Aiming to expand the application and increase adaptability of robotic hand, this paper aims to propose a novel grasping model, called coupled and indirectly self-adaptive (CISA) grasping model, which is the combination of coupled finger and indirectly self-adaptive finger.

CISA grasping process includes two stages: first, coupled and then indirectly self-adaptive grasping; thus, it is not only integrated with the good pinching ability of coupled finger but also characterized with the high flexibility of indirectly self-adaptive finger. Furthermore, a CISA hand with linkage-slider, called CISA-LS hand, is designed based on the CISA grasping model, consisting of 1 palm, 5 CISA-LS fingers and 14 degrees of freedom.

To research the grasping behavior of CISA-LS hand, kinematic analysis, dynamic analysis and force analysis of 2-joint CISA-LS finger are performed. Results of grasping experiments for different objects demonstrate the high reliability and stability of CISA-LS hand.

CISA fingers integrate two grasping modes, coupled grasping and indirectly self-adaptive grasping, into one finger. And a double-linkage-slider mechanism is designed as the switch device.

THE Mercedes‐Benz Model DB‐601A aero‐engine is a development of the Daimler‐Benz Aktiengesellschaft of Stuttgart, Germany, a firm which lias been engaged in the manufacture of automotive and aero‐engines for over fifty years. During the first World War the Daimler Motorcn Gesellschaft of Stuttgart produced the famous Mercedes aero‐engines iii three 6‐cylindcr types with ratings of 160 horse‐power, 180 horse‐power, and 260 horse‐power. Equally renowned were the 160 horse‐power and 230 horse‐power 6‐cylindcr aero‐engines built by Benz and Company in Mannheim. After the war, and as a result of the economic and financial crisis which brought almost complete stagnation to the automotive industry in Germany during the early twenties, these two companies were practically forced to combine their activities in order to survive. Accordingly in 1926 a merger was consummated between the Daimler and Benz organizations. Thus came into being the firm of Daimler‐Benz A.G. and their product, the Mercedes‐Benz line of automotive vehicles and aircraft power plants.