Analysis and implementation of swimming backward for biomimetic carangiform robot fish

The swimming backward for biomimetic carangiform robot fish is analyzed and implemented in this paper. The swimming law of the carangiform robot fish is modified according to the European Eel swimming mode based on the multiple-link structure to implement the backward motion. The motion mode difference between the eel and carangiform fish is discussed, and a qualitative kinematic analysis of the carangiform swimming in water is given to analyze the propulsion produced by the undulation of the multi-links tail. The experiments conducted demonstrate the good performance of the proposed method, and the results are given.

A backward glance of who and what marketing scholars have been researching 1977-2002

Despite the diversity of all those involved within the marketing discipline, all have a stake in maximizing the advancement of marketing knowledge. Without a specific analysis it is difficult to reflect on where a field has been or where it might be heading. The purpose of this chapter is to examine who and what marketing scholars have been researching over the period 1977–2002 using content analysis. This chapter provides longitudinal benchmarking of the ‘‘inputs’’ (authors and institutions) and ‘‘outputs’’ (articles) examining the marketing literature in the four major marketing journals: the Journal of Marketing, the Journal of Marketing Research, the Journal of Consumer Research, and the Journal of the Academy of Marketing Science.

Development of positioning jig for glass capillary bending mechanism

In a bending mechanism for glass capillary, the positioning jig to hold the capillary in place is one of the most important components to ensure the bending quality. The tapered shoulder of the capillary is used as the positioning reference. Since the dimension of the shoulder of individual capillaries varies slightly, the geometry of the capillaries is studied to identify the desired positioning spot on the shoulder. Upon determination of the positioning spot, a positioning jig is designed, which is composed of positioning, holding, and clamping units. A prototype is made and assembled onto the bending mechanism for testing. The testing results show that the mechanism is able to achieve the desired functionalities demanded by the delicate bending process.

Performance of wrought aluminium and magnesium alloy tubes in three-point bending

This present work examines the load carrying capacity, energy absorption and fracture characteristics of wrought magnesium and aluminium alloy tubes in three-point bending. Magnesium alloy AZ31, and aluminium alloys 6063 and 7075, were extruded into cylindrical tubes of both equivalent thickness and mass. A strong thickness effect was present meaning that the AZ31 tube had significantly higher load and energy absorption performance than an equivalent mass 6063 tube, albeit not as high as the 7075 tube. Hinge formation and maximum load was delayed for the magnesium alloy, meaning that a high energy absorption rate persisted to higher deformation displacements than the aluminium alloys. It was also found that fracture during deformation was dependent on the indenter diameter, tube thickness and lower support separation.

Effect of grain size on the performance of extruded magnesium alloy tubes in three-point bending

The performance of extruded AZ31, AZ61 and AM-EX1 tubes was examined in three-point bending. Different extrusion temperatures were used to investigate the effect of grain size on the load-carrying capacity, energy absorption and fracture propensity of the tubes. Results showed that while the peak load increased with a smaller average recrystallised grain size, the retention of large elongated un-recrystallised grains in the microstructure reduced the load. The presence of the large elongated grains also appeared detrimental to the ability of the tube to deform before fracture.

The effect of skin passing on the material behavior of metal strip in pure bending and tension

The metal strip used in roll forming has often been preprocessed by (tension or roller) leveling or by skin-pass rolling, and as a consequence, may contain residual stresses. These stresses are not well observed by the tensile test, but could have a significant effect on the bending and springback behavior. With the advent of improved process design techniques for roll forming, including advanced finite element techniques, the need for precise material property data has become important. The major deformation mode of roll forming is that of bending combined with unloading and reverse bending, and hence property data derived from bend tests could be more relevant than that from tensile testing.

This work presents a numerical study on the effect of skin passing on the material behavior of stainless steel strip in pure bending and tension. A two dimensional (2-D) numerical model was developed using Abaqus Explicit to analyze the affect of skin passing on the residual stress profile across a section for various working conditions. The deformed meshes and their final stress fields were then imported as pre-defined fields into Abaqus Standard, and the post-skin passing material behavior in pure bending was determined. The results show that a residual stress profile is introduced into the steel strip during skin passing, and that its shape and stress level depend on the overall thickness reduction as well as the number of rolling passes used in the skin passing process. The material behavior in bending and the amount of springback changed significantly depending on the skin pass condition.

Backward modelling and look-ahead fuzzy energy management controller for a parallel hybrid vehicle

This paper focuses on a parallel hybrid electric vehicle. It first develops a model for the vehicle using the backward-looking approach where the flow of energy starts from wheels and spreads towards engine and electric motor. Next, a fuzzy logic-based strategy is developed to control the operation of the vehicle. The objectives of the controller include managing the energy flow from engine and electric motor, controlling transmission ratio, adjusting speed, and sustaining battery's state of charge. The controller examines current vehicle speed, demand torque, slope difference, state of charge of battery, and engine and electric motor rotation speeds. Then, it determines the best values for continuous variable transmission ratio, speed, and torque. A slope window scheme is also developed to take into account the look-ahead slope information and determine the best vehicle speed for better fuel economy. The developed model and control strategy are simulated. The simulation results are presented and discussed. It is shown that the use of the proposed fuzzy controller reduces fuel consumption.

Modelling of bending-dominated forming processes of metal sheets

Theoretical solutions, finite element models, and experimental techniques are developed for three major sheet metal forming operations: bending (pure bending and cyclic bending), die bending, and deep drawing. These have been applied to two different commercial quality cold-rolled steels, one stainless steel, and one magnesium alloy.

Analytic study on pure bending of metal sheets

In this work, analytical models of pure bending are developed to simulate a particular type of bend test and to determine possible errors arising from approximations used in analyzing experimental data. Analytical models proposed for steels include a theoretical solution of pure bending and a series of finite element models, based on the von Mises yield function, are subjected to different stress and strain conditions. The results show that for steel sheets the difference between measured and calculated results of the moment-curvature behaviour is small and the numerical results from the finite element models indicate that experimental results obtained from the test are acceptable in the range of the pure bending operation. Further for magnesium alloys, which exhibit unsymmetrical yielding, the algorithm of the yield function with a linear isotropic hardening model is implemented by programming a user subroutine in Abaqus for bending simulations of magnesium. The simulations using the proposed user subroutine extract better results than those using the von Mises yield function.

Comparison of bending of automotive steels in roll forming and in a V-die

Bending in a V-die has been used to indicate the outcome of bending in cold roll forming, although little direct correlation has been performed. In this work direct comparison of the springback in both processes was performed using six samples of automotive steels in a conventional roll forming line where the transverse springback is measured. A bend of similar radius was formed in a V-die and the springback determined. In general, the springback in V-die forming was greater than in roll forming, in some cases by a factor of 2. The theoretical springback angle was determined for all steels using a simple and approximate analytical equation and compared to the experimental roll forming and bending results. While for the roll forming process good agreement was achieved the theoretical values significantly underestimated springback in the V-bending process.