The additive manufacturing technology for ultrasonic consolidation(UC) is to make use of piezoelectric properties of piezoelectric transducer which produces high frequency vibration applied to the metal foil surface and form solid state bonds between metals under certain pressure. In order to obtain better consolidation process parameters, 0.2 mm thick Ti-6Al-4V titanium alloy and 6061 aluminum alloy were consolidated with the UC method, experiments of peeling and surface hardness for consolidation joints were carried out. Firstly, the regularity of peeling strength and surface hardness for consolidation joints with the change of consolidation pressure, oscillator amplitude and heating plate temperature was analyzed, and key process parameters which could improve mechanical properties of the consolidation interface were obtained. Secondly, the microstructure of the consolidation interface was observed by energy dispersive spectrometer (EDS), and the effect of different process parameters on the consolidation interface, and the formation of intermetallic compounds were analyzed, and good consolidation process parameters were obtained. It is found that the larger consolidation pressure, oscillator amplitude and heating plate temperature can result in stronger bonding. The optimum UC pressure of Ti-Al foil is 2.5 kN, the oscillator amplitude is 60 μm, and the heating plate temperature is above 200 ℃. This paper not only focuses on peeling strength and surface hardness, but also analyzes the microstructure of Ti-Al consolidation interface, which can give an opportunity to satisfy the effective consolidation of different materials.

Correction method for improving the accuracy of gap shape measurement using vertical-objective-type ellipsometric microscopy (VEM) was investigated. This method can provide observation with 0.1-μm-order lateral resolution. Since VEM-based measurement uses an optical microscope with high lateral resolution, the measured ellipsometric signal includes polarization change and incident angle unevenness when applying rotating compensator ellipsometry (RCE) to gap shape measurement. The effect of the variations of the ellipsometric signals on the gap measurement accuracy had been theoretically investigated and these could cause errors of more than 10 nm in gap measurements with RCE. Corrections of these errors were necessary for gap shape measurements with nm-accuracy. The proposed method enabled to correct the polarization change and the incident angle distribution due to using optical devices. Evaluation using gaps filled with air or lubricant (poly-α-olefin) demonstrated gap measurement accuracy of about 1 nm. The VEM gap shape measurement using the correction method showed the highest sensitivity for gaps around the contact region, and enabled observation of the differences in the contact state, which depended on small variations in surface roughness of less than 1 nm. This method also achieved to observe confined lubricant film of less than 1 nm in the contact area, which is possible to reduce the contact points between surfaces.

Humans shake hands as a sign of greeting, when they first meet one another, to express a feeling of rapport. For interactions involving a human and a robot, if the robot generates a handshake behavior that is emotionally acceptable to humans, it will lessen any feeling of aversion that the human has when initiating an interaction with the robot. For this reason, in our previous study, a handshake request motion model was proposed, where the robot generated a handshake behavior for the case when the robot actively approached a human. In this model, we studied the motion of a robot actively approaching humans, the handshake request motion from the robot and the start timing of the handshake. However, to promote embodied interaction smoothly, it is necessary for the robot to respond to the handshake requested by humans while still approaching them. Therefore, we developed a handshake robot system that generated a handshake behavior according to the request and response situation while actively approaching a human. First, a handshake response motion model for a handshake with active approach toward a human is proposed, based on an analysis of human handshake behaviors. In this model, the robot generates the response motion while it approaches the human. Furthermore, a switching handshake control with the active approach is developed where the robot generates either the request motion or the response motion, for a handshake according to the behavior of the human. By sensory evaluations, the effectiveness of the robot system using a switching handshake control was demonstrated.

Friction stir welding is a non consumable concrete condition welding course for joining aluminum alloys and is engaged in aerospace, rail, automotive and marine industries. The weld quality of this type depends upon the process parameters such as the rotational speed of the tool, the welding speed and the axial force. In this paper, friction stir welding was used to weld two dissimilar aluminium alloys AA7075 T6 & AA6061 T6 by varying the input parameter namely the rotational speed and maintaining the welding speed, load as constants. Morphological characterization is done using Scanning Electron Microscope while the mechanical properties of the welded specimens are characterized by conducting smooth tensile and hardness test and the values are reported.

Turbine blades need to be repaired to extend their product life, because they are used in highly heated centrifugal fields and often suffer damage such as cracks, chippings, and oxidation thinning. The objective of this study is to perform additive fabrication onto the thin end of a plate using wire and arc-based additive manufacturing and the conduct finish cutting to repair turbine blades made of Inconel 718. It was successfully demonstrated to fabricate a wall structure onto the thin end of a plate with a thickness of 1 to 5 mm with the aimed deposition width while maintaining a constant interlayer temperature. In addition, a finish cutting was conducted on the additionally fabricated wall structure to achieve the same thickness as the thin base plate. It was also shown that there was almost no uncut part on the additive wall surface.

The load cell is an essential sensor for the force measurement systems. The sensitivity of a typical load cell for general force measurement is constant over the full operating range. For high stroke systems such as hydraulic systems, this property is not suitable because of insufficient resolution at the small loading force. High stroke systems require higher sensitivity in the small loading force compared with in the large loading force. In other words, for the high control performance, the smaller loading force is applied, the higher sensitivity is necessary to the systems. The optimal relationship between strain and force can be expressed as a logarithmic function. Based on this relationships, we developed a hybrid load cell which has a piece-wised linear model based on a stack structure. In addition, equipment for loading test was invented to examine and compensate the load cell quantitatively. By using this equipment, compressive force, tensile force and torque can be applied from a small force to a large force in accordance with the seesaw principle. The performance of the proposed system was verified by experiments.

In recent years, video communication systems have found wide application along with cellphones and e-mails for remote communication. Using video communication, partner’s expression and personal space, which are beneficial in providing smooth communication between two remote locations, can be seen. However, it is difficult to perceive depth, since the projected images are only able to display two-dimensional information. Furthermore, during video communication, while user might move around, the view of partner remains unchanged. It is important to see an image including depth information for communication. It is expected that people will be able to communicate smoothly using images including depth information because feelings of shared place are increased by it. Therefore, in this paper, we develop a virtual window communication system by which an image of a remote location through a virtual window is projected based on the head position of the user. In this system, when the positional relationship between the head position of the user and the window changes, the projected image will also change accordingly. Thus, the user can feel as though he or she is looking directly at his or her conversational partner and the surrounding environment through the virtual window. Furthermore, remote pointing is realized using a pointing function in this communication system. This pointing function does not require calibration and can be placed at an arbitrary position using image processing. Then, sensory evaluations were performed to demonstrate the effectiveness of the developed virtual window communication system.

The robotic archwire bending technology has been used clinically to free orthodontic doctors from the heavy labor because of the improvement of the digital medical technology, and the digital expression of orthodontic archwire is necessary to realize the robotic archwire bending. Because of the differences between the human tooth arrangement and the difficulty of archwire shape design, it is difficult to realize the digital expression of orthodontic archwire. A method for the digital expression and interactive adjustment of personalized orthodontic archwire is presented in this paper. The straight section and the transitional section of the brackets are defined according to the reference points of the brackets. The transitional sections of the brackets are built by the mathematical model of Cubic Bezier curve. The process of handmade archwire bending, the method of discretization and combination are considered in the establishment of the mathematical model and model library about special function arch curve. The ways of the adjustment of the straight sections, the deformation of the transitional section shape, the selections of the position and type of special function arch curve are used in the study of the method for the digital expression and interactive adjustment of personalized orthodontic archwire. The interactive adjustment software is designed by the LABVIEW software. The archwire bending experiment is carried out, the error rate of the bent archwire ranged between 1.1% and 6.7% which proves the digital expression and interactive adjustment method of personalized orthodontic archwire for robotic bending is feasible and effective.

In human interaction and communication, not only verbal messages but also nonverbal behaviors such as facial expressions, body movements, gazes and pupil responses play an important role in expressions of talker’s affect. These expressions encourage to read the emotional cues and to cause the sharing of embodiment and empathy. We focused on the pupil response which is closely related to human affect, and developed an embodied communication system in which an interactive CG character generates the pupil response as well as communicative actions and movements such as nodding and body movements by speech input. In addition, it was confirmed that the pupil response is effective for supporting the embodied interaction and communication using the developed system. In this paper, in order to realize the smooth interaction between human and robot, we developed a pupil response system using hemispherical displays for enhancing affective conveyance. This system looks like robot’s eyeballs and expresses vivid pupil response by speech input. We carried out a sensory evaluation experiment under the condition that the developed system speaks. The results demonstrated that the system effectively enhances affective conveyance.

Predicting machine tool performance at the design stage is one way to resolve the time issue and achieve cost savings. Our objective in the present work was to develop a new roll forming machine for curved products comprising a servo motor, ball screw, and rolling-element linear guide, with the support of virtual prototyping technology. First, a multibody simulation model was developed based upon the machine concept to investigate machine dynamic behavior in real time. Then, we proposed an adaptive sliding-mode PID-based controller (ASMPID) to control the manufacturing process. We performed co-simulation between the mechanical structure and the virtual controller to investigate the head unit trajectory and to identify optimal control parameters. Finally, we manufactured a prototype machine to evaluate the machine accuracy and the benefits of the new system. The results indicated that the proposed model including the mechanical structure and the intelligent controller was effective and feasible for designing the roll forming machine. We expect this work to improve the prototyping efficiency of new rolling machines.

In this paper, to mechanize a human ankle joint stretching treatment that is mainly performed by a PT (Physical Therapist), the geometrical relationships among the Ankle joint, Hip joint, Sole, and pushing device rotation center are analyzed using a simple numerical calculation model, and the effectiveness of the model was examined in an actual developed system. The stretching of the ankle joint is an important medical treatment that PTs perform to help their patients to recover their ability to walk and to prevent contracture. Because the ankle joint treatment requires a large amount of force (equal to the subject’s weight) and precise angle control at the same time, manual treatment by PTs has not been replaced by mechanical treatment systems. In a previous study, we developed a new mechanism of ankle joint stretching that involves fixing the length of the subject sitting chair and the device; the novel mechanism can realize comfortable stretching without pain. However, the optimum geometrical relationships among the Ankle joint, Hip joint, Sole, and pushing device rotation center have not been analyzed. In this paper, to develop the effective mechanism of the stretching treatment, the geometrical relationships were analyzed mathematically by using numerical calculation, and the effectiveness of the numerical calculation was confirmed by manufacturing a treatment device comprising two force sensors and two DC motors based on the calculation results. Numerical calculation results show that the PT’s key point of the ankle joint treatment was a position located between the Ankle joint and the pushing device rotation center. The analytical result will effectively promote the development of the mechanical systems used as ankle joint stretching treatment devices.

In the brush-making industry, ferrule processing is an important link in the production of paint brushes, and the hemming of ferrule is one of the most complex processes in ferrule processing. The production of paint-brush ferrule mainly relies on manual or semi-mechanized processes at present, which have a low production efficiency and poor product quality. In order to realize the automated production of ferrules, an automated production system of ferrules, using pneumatic technology and PLC control technology, is designed, and the hemming system is developed in this paper. First, the production process of ferrules is introduced, and the overall scheme of the production system is proposed. Then, the mechanical system, pneumatic system and control system are designed in detail. Next, the stability of the plunger chip and the adjustable mould of the production system are analyzed via the ANSYS Workbench. Eventually, the hemming system prototype is developed, and hemming tests are carried out. The results show that the effect of ferrule hemming is good, and the system meets design requirements.

As a new type of gear transmission, composite curve-face gear transmission is used to transfer the power and composite motion of rotation and movement between the intersecting or interlaced axis. By using the theory of gear meshing, geometrical differential and space cam design, the motion principle and form of the composite curve-face gear transmission were discussed; the movement characteristics of the composite curve-face gear transmission were analyzed, including transmission ratio, rotation, movement and quick-return; the motion stability of the curve-face gear with different pitch curve forms was studied; and the forms of curve-face gear to realize stable and high-speed transmission were obtained. The correctness of the curve-face gear transmission is verified by experiment.

A nonlinear torque estimator for accurately estimating non-measurable transmission-input-shaft torque in a full-scale automotive vehicle with continuously variable transmission is proposed. The estimator is based on a single-degree-of-freedom, nonlinear drivetrain model; it describes the clearance-induced torsional dynamics of the drivetrain and simulates the non-measurable torque arising from measurable engine-output-shaft torque and drive-shaft torque. Parameters of the estimator are identified from time series obtained from the full-scale vehicle via particle swarm optimization. The estimated transmission-input-shaft torque agrees with the physical torque, suggesting that the estimation quality is above 94.5%. Our estimator extrapolates the transmission-input-shaft torque outside the identified time interval and estimates an unknown sample of the torque measured from a separate trial of the experiment. Our estimator is further improved by delaying the time series of input torques.

In this paper, the reduction of the displacement responses of the elevator ropes under earthquake excitation has been investigated. The simultaneous vibrations of main rope and compensation rope in a high-rise building under earthquake excitation have been simulated. The varying length of rope is considered that caused the variation of other rope parameters such as mass, damping and stiffness. In order to reduce displacement responses of the compensation rope and the main rope, an actuator device which will change the tension of the ropes is applied at the compensation sheave. The vibrations of both ropes are analyzed by solving numerically the governing equations. A controller is proposed to restrain the displacement responses of the both ropes. A Genetic Algorithm which minimizes the displacement of the ropes and optimizes the control parameters, is introduced and applied to the high-rise elevator rope under earthquake excitations. The expected parameters are provided by standard deviation method. By using the expected control parameters, the proposed method is applied to control the vibrations of both ropes under some cases of earthquakes which are different with the earthquakes in Genetic Algorithm process. The results of the simulation validate the effectiveness of the proposed control method for reducing the displacement responses of the ropes.

Reverse logistics refers to the goods flow from customer to producer. Returns may be from the development phase, the use phase or from products recovery in end of life. Due to scarcity of natural resources and raw materials, as well their increased processing costs, companies are committed to track sustainable development principles in their activities to ensure competitiveness and profitability. This can be materialized through eco-design practice and committed resources optimization. In this framework, this paper tries to model the relationship between product’s eco-design, resources commitment and reverse logistics. Hence, through sections, binary relationship of eco-design, resources commitment and reverse logistics will be discussed and conceptually modeled. Finally, a case study related to canned tomato packaging will be proposed.

This research discusses how system dynamics is used to develop an educational game, called CANDY OG, to learn how to improve supply chain performance under conflict of key performance indicators (KPIs). Its objective is to explore applicability of system dynamics to design a business game for fostering interpersonal skills. A causal loop diagram is used to confirm the game design so that the participants can learn by playing about importance of understanding other stakeholder’s mental model to improve supply chain performance. The game was played for experiments to evaluate effectiveness of the game design by surveys and other qualitative methods such as samples’ memos during the game, follow-up interviews and participatory observations. Our experimental results suggest a possibility that the game provides experiential learning to develop interpersonal skills at managing conflicts of KPIs, and thus indicate that the use of system dynamics helps to ensure appropriate designing of the game. The originality is a use of system dynamics for designing an educational game, leveraging its capability to analyze mental models of stakeholders in a system.

As an innovative machining process for hole-making, helical milling (also known as orbital drilling) presents great potential in machining aircraft structures due to temperature and cutting force reduction, flexible kinematics, and improved borehole quality. Meanwhile, the application of hybrid robot with their high accuracy and better stiffness are increased in aircraft assembly machining operations. Combining these two advanced technologies, this paper focuses primarily on the investigation of the TriMule hybrid robot elastic deformation during helical milling hole-making process and its influence on the diameter error of machined hole. The elastic deformation of series and parallel parts under cutting force condition was investigated by finite element simulation software SAMCEF. The TriMule robot helical milling experiments were also carried out to determine the variation of hole diameter error, and an offline compensation method with modifying the eccentricity at different hole depth was proposed based on the established diameter error model. From experimental verification results, it can be found that the hole diameter error of TriMule robot helical milling can be reduced and the consistency of hole diameter accuracy can be significantly improved by proposed error compensation method.

The common way to perform five-axis machining is to generate the toolpaths by using CAM software, which usually considers only the interference between the tool and the workpiece. However, in the actual machining process, either the tool assembly may collide with the worktable, or one of the axes may travel over its limits. Once these problems occur, then re-adjustment of the setup location of the workpiece or the tool axis in the CAM software are needed to resolve the problems. Because both are based on trial-and-error, there is no guarantee that the readjustments will work. The objective of this research was to develop an algorithm to compute the domain where the workpiece can be set up without the mentioned problems. The algorithm first calculates machinable domains for all orientations of the tool axes along the toolpaths without traveling over-limit. The intersection of the domains, called initial machinable domain, is where the workpiece can be set up without traveling over the limits of the axes. The next step is to calculate the total interference domain where interference between the tool assembly and the worktable may occur. Subtracting the total interference domain from the initial machinable domain yields the machinable domain where neither over-limit nor interference between the tool assembly and the worktable will occur. Two cases are presented to demonstrate the feasibility of the proposed method. The results in both cases were verified by CAM simulation. The innovation of this research is to propose a method to compute the machinable setup domain which can directly show the setup location without the over-limit and interference issues during the machining process, especially the interference issue between machine components. In addition, it can eliminate the trial-and-error in CAM planning and make the setup domain visible, which makes it convenient and confident for the CAM engineer to determine the setup location.

Given m periodic deliveries performed by a single tractor and a finite set N of cargoes with their arrival times and processing times, we are asked to find a feasible partition of the cargo set N into m disjoint subsets. The workload of a delivery is defined to be the sum of processing times of cargoes assigned to the delivery. The m periodic deliveries are required to be balanced on their workloads. We treat the maximum distance of a workload from a prescribed guiding mark as a balancing criterion. The maximum distance is equivalent to the ordinary maximum workload over the m periodic deliveries when the guiding mark is given to be zero. In the actual assembly plant motivating this study, allocating each cargo to one of interim storage lanes determines a partition of the cargo set N, and the feasibility of a partition of the N depends on the practical fact. In this paper, we propose a dynamic programming based heuristic algorithm which runs in polynomial time and returns a linear partition of a cargo list. Since the maximum distance criterion contains the ordinary maximum workload as a special case, the proposed heuristic can be regarded as a generalization of an existing linear partition procedure of minimizing the maximum sum of processing times for a subsequence of cargoes. We also conduct numerical experiments to demonstrate the performance of the proposed heuristic with a meaningful guiding mark.