Side Members Research Articles

Study of an analytical technique and system for conducting vehicle crash simulations

Various characteristics should be taken into consideration when developing a vehicle. Among them, the head–on collision characteristic may be one of the most important because it requires much development time and cost. During collisions, collapse of the front end into the passenger compartment endangers its occupants. To prevent this situation, dynamic collision energy must be absorbed by deformation of the front end. Among the front end components, the side members absorb most of the energy. To raise their energy absorbing efficiency, these parts should be designed so that they do not break but crush successively like an accordion. We developed two new methods for realising these characteristics using FEM. One is to utilise buckling sensitivity analysis and the other is to utilise buckling mode for the initial deflection of the structure. We then adapted these methods to our Non–linear Collision CAE which are described in some detail.

Dynamic Analysis of Thin-Walled Box Columns Subjected to Axial Crushing Using the Finite-Element Method

Vehicle collision characteristics are among the most important performance parameters to be examined at the design stage. These characteristics are dependent on the collapse mode of the box columns making up the side members of the body. An accordion-type collapse mode in which the columns do not bend but collapse in sequence is ideal. Beads or reinforcements are often used to produce this kind of mode ;however, most of the work done on them has been of an experimental nature owing to the lack of suitable analytical methods such as finite-element models. In this study, it is shown that a mathematically improved finite-element model, which can be run on a supercomputer, makes it possible to conduct a precise crush analysis of beaded columns When the first buckling mode is applied as the initial deflection.

Compression honeycomb door seal

A honeycomb door seal for resiliently sealing a door to a surrounding structure has a semi-rigid base and a plurality of flexible enclosures. A central enclosure, capable of abutting a door, has an outer surface which is connected to a back side member of the seal through a plurality of ribs. A plurality of ribs generally form a common junction at the back side of the structure with each rib extending forwardly at an acute angle with respect to the door contact surface, i.e., the plane of the door. The remaining enclosures are arranged and shaped to provide good recovery and resiliency of the door seal. The seal can be made out of a flexible polymer such as a thermoplastic elastomer or a thermoplastic olefin.

Selection of the parameters of an inductor for heating of a side member for hardening

Selection of the parameters of an inductor for heating of a side member for hardening

Dynamic analysis of thin-walled box columns subjected to axial crushing.

Vehicle collision characteristics are among the most important characteristics to be examined in the design stage. These characteristics are dependent on the collapse mode of the box columns making up the side members of the body. An accordion-type collapse mode in which the columns do not bend but collapse in sequence is most ideal. Beads or reinforcements are often used to produce this kind of mode; however, investigation conducted on them has been mainly through experiments due to an absence of adequate analytical methods such as FEM. In this study, we show that, using a mathematically improved FEM along with a supercomputer, precise crush analysis can be conducted on columns or columns with some beads when the first buckling mode is provided as initial deflection.

Heat treatment of quality low-alloy steels for KamAZ truck side members

Heat treatment of quality low-alloy steels for KamAZ truck side members

Arc scan ultrasonic transducer array

A plurality of transducers is arranged successively on a common impedance matching layer of a resilient material. Each transducer comprises an elongated piezoelectric element having a width expansion vibrational mode, a pair of first and second electrodes attached to opposite surfaces of the element across its thickness and an elongated block of an impedance matching material disposed between the second electrode and the common impedance matching layer. The common impedance matching layer is bent to take the shape of an arch to conform to the surface of a frame structure which is convexed in the direction of propagation of ultrasonic energy. The piezoelectric elements are secured to the frame so that they bridge the parallel side members of the frame. The piezoelectric members are divided into a plurality of subgroups, each composed of successively arranged elements. The piezoelectric elements of a given subgroup are selected and energized during each clock interval for transmission of focused ultrasonic energy. The subgroup to be selected is shifted linearly to the next by at least one element in response to successive clock pulses. Becuase of the convex shape of the array, the transmitted energy is successively angulated to provide arc scan.

Comparison of Nailed Joint Test Methods

Abstract Six different test configurations were studied to evaluate the effect of test methods on the load-slip behavior of nailed joints. The apparati considered are those used by five researchers in addition to that described in ASTM Method for Testing Mechanical Fasteners in Wood (D 1761). The load-slip parameters evaluated were: first and second cycle secant slip moduli at design load, loads at 0.38- (0.015-) and 2.54-mm (0.100-in.) slip, ultimate load, and slip at ultimate load. These parameters were evaluated for joints nailed with 6d and 8d nails in single shear and interlayer (connector) gaps of zero and 0.51 mm (0.02 in.). Douglas fir lumber and plywood were used as main and side members, respectively. The results indicate that first and second cycle slip moduli are highly sensitive to the test apparatus used. Sensitivity decreases as parameters are taken further along the load-slip record. Beyond 2.54-mm (0.100-in.) slip, no statistically significant differences were found as a result of the methods used. The profound effect of interlayer gap on slip modulus is apparent, while the influence of number of nails used in a specimen is insignificant. Finally, the need for accurate slip measurement and three-point support foundation for test specimens loaded in compression is emphasized.

A method for determining the mechanical characteristics of orthotic knee joints.

All orthotic equipment must operate at the highest possible standards of safety and, should structural failure of a loaded component occur, there must be a minimal possibility of injury to the user. Because of the lack of definitive data on the in-service loading of lower limb orthoses it is not possible to base a test procedure on "real" loading conditions. In this paper a method of destructive testing, based on the assumption that the predominant loading consists of bending about the medio-lateral and anterior-posterior axes, is described. This method makes it possible to measure the bending strength of a knee joint side member assembly and to define the brittleness of the failure. It is suggested that the latter definition makes it possible to predict the potential safety of a particular knee joint should in-service failure occur. Some laboratory failures are described and recommendations, based on the test programme, are made for new joint designs.

Fast design of multichannel FIR least-squares filters with optimum lag

This paper is mainly concerned with the efficient design of optimum lag FIR least-squares filters. These filters result when the minimization of the total mean-square error encompasses a time shift between the input signal and the desired response. The solution of this problem leads to a family of normal systems of equations whose associated matrix is the same, while the right-hand side members are parametrized by the lag ranging within a specified interval. The fast algorithm derived here for the determination of the optimum lag filter provides the solutions of the above family of systems by step-up, step-down, Levinson-like order recursions coupled with time updating Kalman-like relations and offers a recursive error capability as well. This is achieved by exploiting the near-to-Toeplitz structure of the matrix and a certain shift invariance property the right-hand side members possess. Finally motivated by the optimum lag problem, systems of equations with near-to-Toeplitz parameters are considered and a fast algorithm is developed. The proposed schemes find important applications in seismic signal processing, system identification, economic forecasting, etc.

The Theoretical and Photoelastic Investigation of Stresses in Chassis Frame Joints

The high stresses in the joints of chassis frames subject to torsion are estimated theoretically and confirmed by tests on photoelastic models. The joints considered are between channel section cross members welded or continuously attached to the webs of channel section side members. The detailed stress distribution in the side members has been estimated using classical plate theory to find the forces resisting the warping displacements of the cross members. Models of joints and a complete frame were made from channel section castings of birefringement material and coated with reflective material to allow the use of a reflection polariscope to analyse the stress distribution. The theoretical results were compared with the results from approximate theories as well as with the photoelastic test results.

Fast Algorithms for Block Toeplitz Systems

This paper is concerned with the solution of systems of equations whose associated matrix is block Toeplitz. First a recursive in nature algorithm is developed for the general problem of block system solution, which is then specialized to block Toeplitz structures. Subsequently cases, where the right hand side member is not arbitrary but rather relates to the Toeplitz matrix are analyzed and a new fast algorithm is deduced, with applications in smoothing and prediction. Finally, within the above context, block banded Toeplitz systems are discussed and two new efficient methods are presented.

Steel for truck side members

Steel for truck side members

Growth rate of fatigue cracks in the frame side members of the 2T�-116 locomotive

Growth rate of fatigue cracks in the frame side members of the 2T�-116 locomotive

An equivalent grid framework for skew plates in flexure

An equivalent grid-framework procedure is presented for the analysis of skew plates in flexure. A rhomboid grid model with side and diagonal members is used to represent a similar element of uniform thickness in the plate. The real value of Poisson's ratio is taken into account. Results for deflexion and bending moment predicted by the equivalent skew grid are given for two examples and compared with those obtained by other, notably finite element, methods.

Steels for side members of truck frames

1. The process developed for normalizing side frames improves the mechanical properties of steel 30T (except the fatigue strength). 2. Two of the steels developed (12G2AF and 12G2F) provide high mechanical properties (including the fatigue strength) under the operating conditions of ZIL side frames. These new steels are undergoing commercial tests.

Grid-Framework Method for Plates in Flexure

A grid-framework procedure is presented for the analysis of plates in flexure. A square or rectangular grid model with side and diagonal members is used to represent a similar element of uniform thickness in the plate. The derivation of the cross-sectional properties of the grid members is based on equating the rotations at the corners of an element of the plate with those at the nodes of its grid model when both are subjected to identical loads. The real value of Poisson's ratio is considered and thus the various boundary conditions can be correctly taken into account. Hence, the method is applicable to all plates in flexure, under the assumption of small deflection theory.

Taller para reparación de automóviles

These workshops are in Osnabruck (Germany), and belong to the firm of Starke & Sohn, which is in the motorcar repair business. The main hall is rectangular, and its roof consists of a light metal structure made up of graceful portal frames, which support the longerons and roofing material; the latter being corrugated fibrocement sheeting. Large skylights run the length of the hall. The side and front walls are mainly glass sheets, thereby giving the workshop exceptional luminosity. The roof is supported on the side members of the portal frames, which have two spans. Ventilation, artificial lighting and air conditioning are fully catered for. Everything is so planned that the vehicles to be repaired shall follow a continuous circuit from the moment of entry until they go out fully repaired.

小型熔接管に対する低温応力緩和法の適用

In this report, we give the mathematical analysis for the mechanism of Low Temperature Stress Relieving method and confirmed the virtues of this method, using comparatively small pipes.For the former object, we adopted the test pieces shown in Fig. 1. After welding, the stress-strain relations of each member are expressed by eqs. (1) & (2), where H is the inherent strain. When both side members are heated to temperature T, the central member will be deformed plastically as eq. (3), where g is the plastic strain. After cooling, T becomes zero. Then we have the relations expressed by eq. (6). In the residual stress of the central member is equal to the yielding stress of the material and the material can be assumed to be perfect plastic body, we have the relation σc1≅σc2. Then we get g??αT. From this relation stresses of each member after cooling can be expressed by eq. (7). In Fig. 2, we showed experimental and theorititcal results.Fig. 4. shows the heating and cooling apparatus for pipes. Test results are summarized in Figs. 7-11 for seam welded pipes and in Figs. 12-16 for butt welded pipes. From these curves we know Low Temperature Stress Relieving method can be sufficiently applied to welded pipes in place of annealing at the point of stress-relieving.By measuring the residual stresses at the outside and inside of the pipe, we know the occurence of bending monents by these treatment.

Month in the Patent Office

A landing skid consists of a box‐frame secured inside an air‐tube 8, the lower portion 9 of which is formed with a tread surface 10, and the ends 5 of which are attached to fuselage struts 24, 27 by links 22, 25, 26. The box‐frame consists of side members 2 secured to clamping strips 12 and the sides of the tube 8 by air‐tight connexions 13, and bolted to two transverse U‐shaped end members against which the ends of the tube are drawn and secured in an air‐tight manner by straps 5. Thin metal rectangular plates 37, 38 form the upper and lower surfaces of the box‐frame, openings 14 being provided to allow free air passage between the upper and lower compartments of the tube 8. The tread 10 is upwardly inclined at its forward end and provided with steel reinforcing wires 11, the forward ends of which protrude beyond the tread and are secured by a clamp 17. The tube 8 is inflated to a pressure of the order 7–8 lb./sq. in. above atmospheric.