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The electric motor and multi-speed transmission hub are essential components for an electric bicycle. Traditionally, these two devices have been designed and manufactured independently. The purpose of this study is to propose a novel electromechanical device that artfully integrates an exterior-rotor brushless permanent-magnet (BLPM) motor into a transmission hub to become a compact structural assembly.

A novel design that integrates a three-phase, 20-pole/18-slot exterior-rotor BLPM motor with a multi-speed transmission hub composed of a six-link, two-degrees-of-freedom (2-DOF) compound planetary gear train (PGT) is presented in this study to overcome inherent drawbacks of existing designs. An analytical approach, based on fundamental circuits, is developed to synthesize the clutching sequences and numbers of teeth of all gears of the PGT.

The integrated device provides six forward speeds, including two underdrives, two direct drives, and two overdrives, as well as two drive modes: the motor-drive mode and the human-drive mode, for electric bicycles. The main feature of the proposed design is the spur gear teeth merged with the pole shoes of the stator to dramatically minimize the detent torque, which is an oscillatory torque that always induces vibration and acoustic noise of the BLPM motor.

The gear teeth on the pole shoes of the stator provide functions not only for transmission, but also act as dummy slots for adjusting the magnetostatic field of the BLPM motor to effectively reduce the detent torque. The peak value of the detent torque of the integrated design is only 9 percent of the original BLPM motor with identical magnet properties and motor dimensions. Such a feature is contributive in suppressing the vibration and acoustic noise of the electric bicycle's BLPM motor. A BLPM motor rated at 310 W and 250 r/min for the integrated device is presented and analyzed by using the commercial finite-element package Ansoft/Maxwell 2D Field Simulator.

The purpose of this paper is to present new locomotion and steering modules conceived and designed for rescue serpentine robots with enhanced climbing ability. The locomotion modules apply sock locomotion technology that allows great motion efficiency in rubble and confined environment due to the very high propulsion ratio. The steering joints guarantee good orientation dexterity by exploiting actuation based on smart materials.

Great attention and time is dedicated to the design phase, digital mock‐upping and virtual comparative assessment of different solutions. Mechatronic interdisciplinary design methodology including mechanisms analysis, sensory actuation issues and functional materials characterization, control and communication integration has been adopted.

The locomotion modules are revised and updated versions improving climbing ability of the socked locomotion module originally proposed by the authors. New steering modules with high orientation workspace, based on smart actuation, are introduced.

The evaluation of the findings on the field is planned but no experimental result is today available.

Agile serpentine robots are requested for quick and safe rescue and special risky interventions in environments where dense vegetation, rubble and confined spaces prevent human presence. These robots offer invaluable potential help in such risky interventions mainly by being agile in exploring the environment, robust, low cost, reliable, and tele‐operated.

The paper presents original issues in terms of concept and design of instrumental (locomotion and steering) modules for composing modular rescue robots with very high locomotion agility and climbing performances.

Three-dimensional exploded view is a schematic representation of a product anticipated for performing assembly or disassembly operations. Exploded view is found in many applications, such as product instructional materials, repair and maintenance handbooks. This paper aims to propose an efficient exploded view generation technique based on assembly coherence data and disassembly feasibility testing, and illustrate it on various configurations of assemblies.

The proposed methodology extracts the assembly contact information between the constituent parts and geometric feasibility relation matrix based on the common mating surface of part pairs in liaison and assembly collision detection. These data are further used for exploded view generation.

The proposed exploded view generation method determines the possible disassembly sequences and simplifies the procedure in determining the number of disassembly levels.

The procedure consumes more time for the products with large number of part counts having numerous non-ruled surfaces.

The proposed method is effectively used to solve assemblies, where parts are assembled through oblique orientations. The method is found successful in generating exploded view for products with large number of parts through collision-free paths.

The purpose of this paper is to develop an efficient hybrid method that can collectively address assembly sequence generation (ASG) and exploded view generation (EVG) problem effectively. ASG is an act of finding feasible collision free movement of components of a mechanical product in accordance with the assembly design. Although the execution of ASG is complex and time-consuming in calculation, it is highly essential for efficient manufacturing process. Because of numerous limitations of the ASG algorithms, a definite method is still unavailable in the computer-aided design (CAD) software, and therefore the explosion of the product is not found to be in accordance with any feasible disassembly sequence (disassembly sequence is reverse progression of assembly sequence). The existing EVG algorithms in the CAD software result in visualization of the entire constituent parts of the product over single screen without taking into consideration the feasible order of assembly operations; thus, it becomes necessary to formulate an algorithm which effectively solves ASG and EVG problem in conjugation. This requirement has also been documented as standard in the “General Information Concerning Patents: 1.84 Standards for drawings” in the United States Patent and Trademark office (2005) which states that the exploded view created for any product should show the relationship or order of assembly of various parts that are permissible.

In this paper, a unique ASG method has been proposed and is further extended for EVG. The ASG follows a deterministic approach to avoid redundant data collection and calculation. The proposed method is effectively applied on products which require such feasible paths of disassembly other than canonical directions.

The method is capable of organizing the assembly operations as linear or parallel progression of assembly such that the assembly task is completed in minimum number of stages. This result is further taken for EVG and is found to be proven effective.

Assembly sequence planning (ASP) is performed most of the times considering the geometric feasibility along canonical axes without considering parallel possibility of assembly operations. In this paper, the proposed method is robust to address this issue. Exploded view generation considering feasible ASP is also one of the novel approaches illustrated in this paper.

Special software in a CAD system can help a designer evaluate an assembly and redesign it for automation.

This paper aims to fulfil a need to identify assembly interfaces from existing products based on their Assembly Process Planning (APP). It proposes a tool to identify assembly interfaces responsible for reused components integration. It is integrated into a design for mixed model final assembly line approach by focusing on the identification of assembly interfaces as a generic tool. It aims to answer the problem of interfaces’ identification from the APP.

A tool is developed to identify assembly interfaces responsible for reused component integration. It is based on the use of a rule-based algorithm that analyses an APP and then submits the results to prohibition lists to check their relevance. The tool is then tested using a case study. Finally, the resulting list is subjected to a visual validation step to validate whether the identified interface is a real interface.

The results of this study are a tool named ICARRE which identify assembly interfaces using three steps. The tool has been validated by a case study from the helicopter industry.

As some interfaces are not contained in the same assembly operations and therefore, may not have been identified by the rule-based algorithm. More research should be done by testing and improving the algorithm with other case studies.

The paper includes implications for new product development teams to address the difficulties of integrating reused components into different products.

This paper presents a tool for identifying interfaces when sources of knowledge do not allow the use of current methods.

Instructional materials enhance the teaching/learning process by exhibiting information necessary to acquire knowledge and skills. Focuses on printed forms of instructional materials and provides detailed information, including examples, on five types of job performance aids, three types of instruction sheets, and two types of modules. Checklists of considerations that affect the quality of finished products are also provided. Job performance aids (JPAs)provide procedural or factual guidance in the performance of tasks. They store essential details in a variety of functional forms for use just before or during task performance. Research shows that JPAs are a cost‐effective supplement or alternative to training. They reduce the time needed to master task performance and facilitate the transfer of learning from the training setting to the job. Instruction sheets assure that all trainees have the same complete and accurate information for performing practical work and for completing assignments. These sheets also help manage large groups of trainees with diverse abilities who are working simultaneously at several different tasks. Modules are carefully structured documents which facilitate self‐directed and self‐paced learning. While their components may vary, modules typically include learning objectives, an introduction, instructional content, directions, learning activities, and test questions with feedback answers. With modules, trainees assume personal responsibility for their progress. Regardless of the care used in their preparation, all types of instructional materials must be evaluated prior to general use. Presents a comprehensive quality control procedure for confirming effectiveness and value. This was prepared to enhance both formal classroom instruction and individual study. Figures, tables, checklists, appendices, and a glossary of keywords and terms, supplement the text in explaining the content.

The subject of the paper is the mechatronic design of a novel robotic hand, cassino-underactuated-multifinger-hand (Ca.U.M.Ha.), along with its prototype and the experimental analysis of its grasping of soft and rigid objects with different shapes, sizes and materials. The paper aims to discuss these issues.

Ca.U.M.Ha. is designed with four identical underactuated fingers and an opposing thumb, all joined to a rigid palm and actuated by means of double-acting pneumatic cylinders. In particular, each underactuated finger with three phalanxes and one actuator is able to grasp cylindrical objects with different shapes and sizes, while the common electropneumatic operation of the four underactuated fingers gives an additional auto-adaptability to grasp objects with irregular shapes. Moreover, the actuating force control is allowed by a closed-loop pressure control within the pushing chambers of the pneumatic cylinders of the four underactuated fingers, because of a pair of two-way/two-position pulse-width-modulation (PWM) modulated pneumatic digital valves, which can also be operated under ON/OFF modes.

The grasping of soft and rigid objects with different shapes, sizes and materials is a very difficult task that requires a complex mechatronic design, as proposed and developed worldwide, while Ca.U.M.Ha. offers these performances through only a single ON/OFF or analogue signal.

Ca.U.M.Ha. could find several practical applications in industrial environments since it is characterized by a robust and low-cost mechatronic design, flexibility and easy control, which are based on the use of easy-running components.

Ca.U.M.Ha. shows a novel mechatronic design that is based on a robust mechanical design and an easy operation and control with high dexterity and reliability to perform a safe grasp of objects with different shapes, sizes and materials.

The five basic steps outlined in last month's article brought the student to the task of preparing a pictorial view from an orthogonal drawing. This, together with the reverse but easier technique of producing an orthogonal drawing from a pictorial view, is the foundation on which can be built the ability to produce lucid freehand sketches or formal drawings.