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The essence of the conceptual design is getting the innovative projects or ideas to ensure the products with best performance. It has been proved that the theory of inventive problem solution (TRIZ) is a systematic methodology for innovation. The purpose of this paper is to illustrate the design of an adaptive robotic gripper as an engineering example to show the significance and approaches of applying TRIZ in getting the creative conceptual design ideas.

Gripping and holding of objects are key tasks for robotic manipulators. The development of universal grippers able to pick up unfamiliar objects of widely varying shapes and surfaces is a very challenging task. The requirement for new adaptive grippers is the ability to detect and recognize objects in their environments.

The main aim of this work is to show a systematic methodology for innovation as an effective procedure to enhance the capability of developing innovative products and to overcome the main design problems. The TRIZ method will be utilized in order to eliminate the technical contradictions which appear in the passively adaptive compliant robotic gripper.

The design of an adaptive robotic gripper as an engineering example is illustrated in this paper to show the significance and approaches of applying TRIZ in getting the creative conceptual design ideas.

The purpose of this paper is to develop a robotic tooth brushing simulator mimicking realistic tooth brushing motions, thereby facilitating greater understanding of the generation of realistic tooth brushing motion for optimal design of toothbrushes.

Tooth brushing motions were measured via a motion capture system. Different motion patterns of brushing were analysed. A series of elliptical motion segments were generated by interpolating ellipse‐like trajectories. Furthermore, a path generation algorithm for brushing simulation was proposed. A path planning system incorporating robot motion control was developed to simulate realistic tooth brushing. The generality and efficiency of the proposed algorithm was demonstrated through simulation and experimental results.

The interpolation of ellipse‐like trajectories can generate elliptical motion segments. Furthermore, realistic tooth brushing can be achieved by integrating the elliptical motion segments into the path generated from the surfaces of teeth. The brushing simulator demonstrated good reproducibility of clinically standardized tooth brushing.

A robotic toothbrush assessment system is a potential application to the robotic tooth brushing simulator by incorporating control of brushing variables, including brushing pressure, speed and temperature.

This study demonstrates the feasibility of using robotic simulation techniques towards improved realistic human tooth brushing motions simulation for optimal design of tooth brushes.

This paper presents an algorithm for the generation of mechanical assembly sequences.

The algorithm employs an adjacency matrix, and uses three different mathematical patterns of subassemblies to generate automatically all geometrical feasible assembly sequences.

This algorithm cannot only generate automatically all geometrical feasible assembly sequences but also reduce the number of sequences.

Assembly modeling is more completed than that of previous research; the method is able to automatically generate all possible assembly sequences and be implemented easily with program; and this paper makes use of exact mathematical equations describing every subgroup of the three‐subassembly patterns.

The purpose of this paper is to design a microgripper that can achieve nondestructive gripping of a miniaturized ultra-thin-walled cylindrical part.

The microgripper is mainly made of an inflatable silica gel gasbag, which can minimize the damage to the part in the gripping process. This paper introduces the design principle of a flexible air-filled microgripper, which is applied in an in-house microassembly system with coaxial alignment function. Its parameters and performance specifications have been obtained by simulation, experiment demarcating. The results show that the microgripper is able to grasp an ultra-thin-walled part non-destructively.

For the microgripper, finite element simulations and experiments were carried out, and both results indicate that the microgripper can achieve nondestructive gripping of a miniaturized ultra-thin-walled cylindrical part, with good stability, great grasping force and high repeat positioning accuracy.

Gripping the ultra-thin-walled part may lead to deformation and destruction easily. It has been a big bottleneck hindering successful assembly. This article introduces a novel microgripper using an inflatable sac. The work is interesting from an industrial point of view for a specific category of assembly applications. It provides a theoretical guidance and technical support to design a microgripper for a miniaturized ultra-thin-walled part of different sizes.

Machining fixtures must fit exactly the work piece to support it appropriately. Even slight change in the design of the work piece renders the costly fixture useless. Substitution of traditional fixtures by a programmable multi‐robot system supporting the work pieces requires a specific control system and a specific programming method enabling its quick reconfiguration. The purpose of this paper is to develop a novel approach to task planning (programming) of the reconfigurable fixture system.

The multi‐robot control system has been designed following a formal approach based on the definition of the system structure in terms of agents and transition function definition of their behaviour. Thus, a modular system resulted, enabling software parameterisation. This facilitated the introduction of changes brought about by testing different variants of the mechanical structure of the system. A novel approach to task planning (programming) of the reconfigurable fixture system has been developed. Its solution is based on constraint satisfaction problem approach. The planner takes into account physical, geometrical, and time‐related constraints.

Reconfigurable fixture programming is performed by supplying CAD definition of the work piece. Out of this data the positions of the robots and the locations of the supporting heads are automatically generated. This proved to be an effective programming method. The control system on the basis of the thus obtained plan effectively controls the behaviours of the supporting robots in both drilling and milling operations.

The shop‐floor experiments with the system showed that the work piece is held stiffly enough for both milling and drilling operations performed by the CNC machine. If the number of diverse work piece shapes is large, the reconfigurable fixture is a cost‐effective alternative to the necessary multitude of traditional fixtures. Moreover, the proposed design approach enables the control system to handle a variable number of controlled robots and accommodates possible changes to the hardware of the work piece supporting robots.

The purpose of this paper is to provide a method for the generation of information machines for part mating process diagnosis. Recognition of contact states between parts during robotized part mating represents a significant element of the system for active compliant robot motion. All proposed information machines for contact states recognition will recognize one of the possible contact states even when irregular events in the process occur, and the active motion planner will continue to send commands to robot controller according to the planned trajectory.

The presented framework is based on the general theory of automata and formal languages. Starting from possible regular contact states transitions in part mating, the authors create an automaton for diagnostics, which, besides regular, accepts all irregular (observable and unobservable) process sequences.

Contact states do not appear arbitrarily during regular processes, but in certain context. Theory of automata represents a solid basis for contextual recognition and diagnosis of irregularities in part mating.

The proposed methodology is elaborated and experimentally verified using an example of cylindrical part mating, and stick-slip effect as an observable irregularity. The future work will address the generation of diagnosers for other types of part mating tasks and extension of the set of observable irregularities.

The process diagnosis increases the robustness of active compliant motion system.

Although very important feedback information provider for active motion planner, part mating process monitoring was not frequently addressed in the past. In this paper, the authors propose a methodology for generation of part mating process diagnoser that is based on general automata theory.

The purpose of this paper is to conduct a reliable remote manipulation with good contact perception of the remote site. The long-term experience of the authors’ repeatedly confirm that the highest relevance lies in monitoring the wrench acting at a structurally weak point of the work piece rather than monitoring the wrench experienced by the robot end-effector.

The approach followed here is to sense the wrench at the interface of the robot end-effector and the environment. Position and orientation data and environment model are used to arrive at the contact point in real time. The intent of remote contact procedure is understood based on the knowledge of motion trajectory. All the above information is used to develop a wrench transformation to obtain the force diagrams.

The haptic solutions greatly suffer from objectivity, and therefore may result in inconsistency in an operator’s role. Intermediary telepresence through the visual communication of the wrench at the remote site in the form of force diagram provides excellent consistency across the operators and operations. Observing six components of the wrench in separate graphs does not provide on-line error estimate. Force diagrams suggested in the paper are found to be highly effective in perceiving the wrench.

The contact mode operations like assembly, surgery, docking, etc. still suffer due to the lack of easily perceivable wrench visualization. This paper provides solution to such practical issues.

The concept is original, and has evolved steadily over a period of time.

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 develop a dual peg-in-hole insertion strategy. Dual peg-in-hole insertion is the most common task in manufacturing. Most of the previous work develop the insertion strategy in a two- or three-dimensional space, in which they suppose the initial yaw angle is zero and only concern the roll and pitch angles. However, in some case, the yaw angle could not be ignored due to the pose uncertainty of the peg on the gripper. Therefore, there is a need to design the insertion strategy in a higher-dimensional configuration space.

In this paper, the authors handle the insertion problem by converting it into several sub-problems based on the attractive region formed by the constraints. The existence of the attractive region in the high-dimensional configuration space is first discussed. Then, the construction of the high-dimensional attractive region with its sub-attractive region in the low-dimensional space is proposed. Therefore, the robotic insertion strategy can be designed in the subspace to eliminate some uncertainties between the dual pegs and dual holes.

Dual peg-in-hole insertion is realized without using of force sensors. The proposed strategy is also used to demonstrate the precision dual peg-in-hole insertion, where the clearance between the dual-peg and dual-hole is about 0.02 mm.

The sensor-less insertion strategy will not increase the cost of the assembly system and also can be used in the dual peg-in-hole insertion.

The theoretical and experimental analyses for dual peg-in-hole insertion are proposed without using of force sensor.