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This paper aims to automate the welding operation that motion control, sensor integration and coordination with the welding power source. Therefore, there is a need for sophisticated technologies to control precisely the process in terms of positioning the welding torch, and controlling the welding parameters through the use of correct devices which are aided by appropriate control tools and techniques.

A new seam tracking methodology, named sewing technique, has been introduced for the welded joints available in computer-aided design (CAD) environment. This methodology gives the seam path by drawing a line through the adjacent centroids of curve fitted in the weld joint volume. Obtained geometric path and kinematic constraints are given as input to the modeled robot for performing welding operation followed by desired trajectory.

In this investigation, a novel and efficient weld seam technique has been developed to produce uniform welded joints. The key feature of this approach is that the initial and end positions of the weld seams can be obtained easily. Because of this, the robot can be controlled flexibly during welding operation.

This investigation deals with the development of an automated seam tracking methodology for the welded joints available in CAD environment. Validation of the developed methodology has been done through simulation results while performing welding operations for different weld profiles.

The purpose of this study is to identify an innovative solution for the power transmission gearbox of concrete mixers, according to the specifications provided by the company.

A tailored systematic design approach (inspired to the German systematic framework) has been adopted to comprehensively gather the company specifications and perform in-depth design space explorations. Subsequently, an iterative embodiment design approach has been followed to identify the size of the components for the preferred concept, by using acknowledged mechanical design procedures and finite element analysis tools.

An innovative cycloidal gearbox has been developed, by merging the kinematics underpinning the classical cycloidal drives and the Wolfrom planetary gearbox. The resulting concept provides high reduction rates with a very high overload capacity.

The main limitation of the studies is the absence of in-depth evaluations usually performed in the detail design phase. However, this limitation is a direct consequence of the company specifications, which only asked to find a preferred concept and to perform preliminary evaluations. Accordingly, the subsequent design optimization are intended to be performed by the company’s staff.

The present paper shows an original design approach, opportunely tailored to the design of innovative gearboxes. It can be conveniently adapted and reused by designers involved in similar tasks. Moreover, the designed cycloidal gearbox paves the way for important innovations in the field of concrete mixers, allowing to design more robust and compact devices.

The mechanization of the meat cutting companies has become essential due to the lack of skilled workers and to working conditions. This paper deals with the analysis of human gestures in order to improve the performance of a redundant robotic cell. The aim is to define optimization criteria linked to the process and the human gesture analysis to improve the cutting process with a redundant robotic cell.

This paper deals with an optimized path planning of complex tasks based on the human arm analysis. The first part details the operator's manual work. The robotized cutting strategy using bones as a guide associated with an industrial force control leads to the tasks redefinition. Thus, the analysis of the arm during the tasks is presented. With a robotic model, the authors evaluate the relevance of two criteria (kinematic and mechanical) that the operator naturally manages. These criteria are used to improve the robotized cutting process by using redundancy. Simulation work and experimentation are presented to show the enhanced performance.

The paper explains how to define optimization criteria based on human arm analysis to realize cutting operations which require force or dexterity performance. It presents a study on the criteria weighting on a robotic arm model established through human arm analysis. The optimized cutting process clearly shows improvement.

The scalability of the ham implied the definition of iterative trajectories to follow the curvature of the bone. Due to the use of an industrial force control, no online optimization can be achieved. The off-line optimization implies that the boundary of the trajectory space is technically feasible. Nevertheless, more information has to be extracted from the deboning process such as vision data in order to improve cutting quality.

This study was carried out within the framework of several national and European projects (FUI SRDViand, ANR ARMS, FP7 Echord Dexdeb) in collaboration with ADIV (Meat Institute Development Agency). The redundant robotic cell was developed and implemented at ADIV and used for feasibility studies in connection with SME/SMI French sector.

The paper deals with the cutting of soft bodies such as meat and complex human gesture analysis, which constitute an innovative challenge for the coming years in order to help or replace humans in industrial meat companies with difficult working conditions.

The robot offers interesting capabilities, but suffers from a lack of stiffness. The proposed solution is to introduce redundancies for the overall improvement of different capabilities. The management of redundancy associated with the definition of a set of kinematic, mechanical and stiffness criteria enables path planning to be optimized.

The resolution method is based on the projection onto the kernel of the Jacobian matrix of the gradient of an objective function constructed by aggregating kinematic, mechanical and stiffness weighted criteria. Optimized redundancy management is applied to the 11-DoF (degrees of freedom) cells to provide an efficient placement of turntable and track. The final part presents the improvement of the various criteria applied to both 9-DoF and 11-DoF robotic cells.

The first application concerns the optimized placement of a turntable and a linear track using 11-DoF architecture. Improved criteria for two 9-DoF robotic cells, a robot with parallelogram closed loop and a Tricept are also presented. Simulation results present the contributions of redundancies and the leading role of the track.

The redundancy-based optimization presented and the associated simulation approach must be completed by the experimental determination of the optimization criteria to take into account each machining strategy.

This work in robotics machining relates to milling operations for automotive and aerospace equipment. The study is carried out within the framework of the RobotEx Equipment of Excellence programme.

The resolution method to optimized path planning is applied to 9- and 11-DoF robotic cells, including a hybrid robot with a parallelogram closed loop and a Tricept PKM.

The purpose of this paper is to study the integration between this technology and barrel finishing (BF) operation to improve part surface quality. Fused deposition modeling (FDM) processes have limitation in term of accuracy and surface finishing. Hence, post-processing operations are needed. A theoretical and experimental investigations have been carried out.

A geometrical model of the profile under the action of machining is proposed. The model takes into account FDM formulation and allows to predict the surface morphology achievable by BF. The MR needed in the model is obtained by a particular profilometer methodology, based on the alignment of Firestone–Abbot (F–A) curves. The experimental performed on a suitable geometry validated geometrical model. Profilometer and dimensional measurements have been used to assess the output of the coupled technologies in terms of surface roughness and accuracy.

The coupling of FDM and BF has been assessed and characterized in terms of obtained part surfaces and dimension evolution. Deposition angle strongly affects the BF removal speed and alters nominal dimensions of part. The geometric profile model gave interesting information about profile morphology and machining mechanism; moreover, the height prevision allows to estimate BF working time to accomplish part requirements.

The prediction of the geometric profile as a function of FDM fabrication parameters is a powerful tool which permits to investigate surface properties such as mechanical coupling or tribological aspects. The coupling of BF and FDM has been assessed and now optimization of this process can be performed just evaluating effects of parameters.

This research has been focused to an industrial application, and results can be used in a computer-aided manufacturing. The prevision of surface obtainable by this integration is a tool to find the part optimum orientation to accomplish the drawing requirements. Both the experimental findings and the model can guide operator toward a proper process improvement, thus reducing or eliminating expensive trial and error phase in the post-processing operation of FDM prototypes.

In this paper, a novel model has been presented. It allows to know in advance profile morphology achievable by a specific surface of a FDM part after a determined BF working time. A particular application of FA curves gives the MR values.

The cutting and extruding processing technology for ceramics based on the edge-chipping effect is a new contact removal machining method for hard, brittle materials such as engineering ceramics. This paper aims to provide an important reference to understand the tool wear mechanism and the wear law of this new processing technology.

The real-time temperature monitoring and the observation of micro-morphology are used to analyse the wear characteristics of the tool face. In addition, the research focuses on the influence of three processing parameters (axial feed rate, thickness of flange and depth of groove) on characteristics including tool wear.

The temperature variation shows that the new processing technology improves the tool temperatures condition. The tool is worn mainly by mechanical friction including abrasive wear, and the flank face also suffers the sustained scratching of residual materials on the rough machining surface. With increased feed rate, the wear of the rear face of the major flank initially decreased and then increased. As the depth of the retained flange increases, the wear became worse. The wear initially decreased and then increased with increasing depth of groove.

Study on the new processing technology is still in its early stages. Therefore, researchers are encouraged to test the proposed propositions further.

The machining process itself destroys materials, albeit a controllable manner: based on this principle, the authors proposed a new machining technology based on cracks driven by edge chipping. In this way, the surface of such ceramics is removed. Therefore, the research provides a new method for reducing processing costs and promoting the extensive application of engineering ceramic materials.

The cutting and extruding processing technology based on cracks driven by edge-chipping effect makes full use of the stress concentration effect caused by prefabricated defects, and the edge-chipping effect which occurs during machining-induced crack propagation. The wear mechanism and law of its tool is unique than other machining ways. This paper provides an important reference to understand the tool wear mechanism and the machining mechanism of this new processing technology. With the application of this study, the ceramics could be removed with less energy consumption and the tools with the hardness of lower than its own one. Therefore, it could not only reduce the processing costs but also promote the extensive applications of engineering ceramic materials.

Discusses the 6th ITCRR, its breadth of textile and clothing research activity, plus the encouragement given to workers in this field and its related areas. States that, within the newer research areas under the microscope of the community involved, technical textiles focuses on new, ‘smart’ garments and the initiatives in this field in both the UK and the international community at large. Covers this subject at length.

Recent requirements for drive systems in robotic technology, mainly for their performance, performance and weight ratio, compactness with minimal internal structure and with the integration of main functional parts, lead to intensive application of new, non‐traditional solutions. One of the possible approaches to a non‐traditional solution of drive systems in robotic technology is the application of pneumatic artificial muscle (PAM). The purpose of this paper is to review the designs and applications of the under‐pressure artificial muscle (UPAM) and the creation of non‐standard modules for robotic technology based on PAM.

Certain part of the disadvantages of an over‐pressure PAM can be solved by the use of an UPAM. As a performance output, UPAM principle guarantees linear movement along the axis with relevant traction force. This UPAM demonstration is evaluated as the drive in mechanic constructions.

Theoretical calculations, which have been performed, as well as experimental tests and evaluations of the model of this muscle have confirmed an agreement with theoretical relationships valid for PAM generally. The module TMPAM with lengthening action element is principally based on the change of input pressure energy, shape and volume change of action element into output mechanical (power, kinetic) energy. The analysis of the results of measurements (set of measurements, four samples of action element) of the given relationships allows to say that the tractive power F and the lift grow with the change of geometric arrangement of the action element in the box of the driving unit. The output parameters of the TMPAM can be regulated by the number of action elements integrated in the unit (creating two‐element and more‐elemnet parallel sets).

The UPAM maintains all advantages of the principle and recent constructions of the PAM, as well as lightness and compactness of the design. The results confirm that this construction principle of the translation modules is suitable mainly for small lifts, lower load and movements, where even, soft motion is required.

On the basis of author's own solutions of the underpressure artificial muscle (UPAM, original patent) and non‐traditional translation module (TMPAM, original design), the paper evaluates and generalizes the findings obtained from the use of PAM in robot construction.

The purpose of this study/paper is to present the design and implementation of a novel vending machine concept based on desktop-scale extrusion additive manufacturing (AM). Due to cost, access to AM technologies at academic institutions tends to be limited to upper-level courses to support project-based coursework. However, with the decreasing cost of desktop-scale AM technology, there is potential to improve student access to such technologies and provide more opportunities for AM education.

The authors present the design and implementation of an AM “vending machine” that is powered by desktop-scale extrusion-based AM systems. This system intends to provide students broad, unrestricted access to entry-level AM tools and promote informal learning opportunities.

Student users of the AM vending machine are found to be primarily engineering majors at various levels in their studies. Manufactured parts are evenly split between functional and decorative parts, though 75 per cent of students are creating their own designs rather than simply printing found design files.

Future work will focus on improving the system’s ease-of-maintenance, lowering the barrier to entry with a simpler user interface and establishing a method for better recording part and user information.

The interface of the AM vending machine lowers the barrier of entry into engaging with AM and places this emerging technology in a familiar and “safe” context. It provides students at various levels and disciplines the opportunity to fabricate parts for classroom and personal projects.

A “vending machine” system may have far-reaching implications for public access and use of AM. Such broad access has the potential to further educate and impassion the public about the potential of AM.

This work represents the creation and assessment of the world’s first AM vending machine.

The purpose of this paper is to report on the use of a combination of indirect selective laser sintering (SLS) and machining processes to create injection mould tools, an approach designed to offer the capability to create conformal cooling channels in the core/cavity inserts together with the levels of surface finish and accuracy required to meet typical injection mould tool specifications.

The research has been pursued through three industrial case studies. In each study, existing injection mold inserts have been redesigned to give a conformally cooled tool. These have then been manufactured using indirect SLS, high‐speed machining, electro‐discharge machining and polishing. The inserts have been evaluated in industrial trials to assess their performance in terms of cycle time, energy usage, durability and quality. The insights gained from the three case studies have then been developed into a series of design rules, which may be applied in the development of tooling for new applications.

The results show that significant productivity improvements and energy use reductions in injection moulding are possible through the implementation of conformal cooling, and that the material has sufficient wear resistance to be used in production applications. However, it is recommended that modelling is always used to understand the impact of conformal cooling channels, and manufacture is carefully planned to ensure that the required internal geometry is created.

The paper presents new results on the impact of conformal cooling on the productivity and energy efficiency of injection moulding, and on the durability of the indirect SLS material in injection moulding applications. A novel “cut‐out volume” technique for powder clearing is also presented, along with a set of design rules to support further application of the work.