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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.

This paper's objective is to explain the concept of proper kinematic constraint to guide requirements‐driven design of mechanical assemblies and to connects proper constraint to the datum flow chain (DFC) and key characteristics (KCs).

The paper presents proper constraint as a way to support the goal of placing key parts in particular geometric relationships with respect to one another so that a DFC can deliver KCs unambiguously. Such a DFC is said to be competent. Additionally, a competent DFC is robust in the sense that the constraint relationships between parts retain their definition and effect under all allowed variations in parts.

Failure to provide proper constraint can lead to undesired consequences including locked‐in stresses and difficult or inconsistent assembly. Some designs need to be over‐constrained, and this requires very careful control and tight tolerances on the over‐constrained degrees of freedom in order to avoid or at least understand the consequences listed above.

Mathematical methods exist to test designs for proper constraint. The simplest, and occasionally unsuccessful, is the Kutzbach criterion. Screw theory is the most reliable method but its application requires extra knowledge and mathematical tools.

Most CAD software and tolerance analysis software do not test designs for their state of constraint. The engineer needs to take account of this independently and be aware of the limitations of software as a guide. Tolerance analysis software that does not take account of constraint may yield incorrect answers.

The paper reinvigorates a once‐well‐known principle and makes engineers aware of it. It also links this concept to the concepts of DFC and KCs and supports a mathematically‐based method for designing assemblies.

Selection of an effective grasp of a complex object using a multifingered gripper is a challenging problem because of the many possible grasp positions that are typically available.

Given the geometrical description of the particular object feature to be grasped, all feasible grasps are performed in offline simulation using a geometrically accurate model of the desired gripper. The six‐dimensional convex hull for each grasp is computed and archived. This convex hull indicates the span of forces and torques that the grasp can resist. When a grasp is needed the force/torque due to the total object weight is estimated and the best grasp is selected. The selected grasp has minimum peak contact force consistent with equilibrium.

Experimental trials with several complex object show the method is capable of producing grasps which can support the object and resist external force/torque.

An accurate geometrical description of the feature to be grasped must be known in advance. This would typically be a cylindrical or prismatic portion of the object.

There are many environments in which a dexterous multifingered gripper must be used due to the variety of objects which must be grasped. The results indicate that effective grasps can be selected for complex objects from a database of simulated grasps.

The primary contribution of this paper is the use of a database of simulated grasps on simple graspable features to synthesize grasps on complex objects.

Robotic hands are still a long way from matching the grasping and manipulation capability of their human counterparts, but computer simulation may help us understand this disparity. We present our publicly available simulator, and describe our research projects involving the system including the development of a human hand model derived from experimental measurements.

Unlike other simulation systems, our system was built specifically to analyze grasps. It can import a wide variety of robot designs by using standard descriptions of the kinematics and link geometries. Various components support the analysis of grasps, visualization of results, dynamic simulation of grasping tasks, and grasp planning.

The simulator has been used in several grasping research problems and can be used to plan grasps for an actual robot. With the aid of a vision system, we have shown that these grasps can be executed by a robot.

We are currently developing methods to handle deformable surfaces, tendon driven models, and non‐ideal joints in order to better model human grasping.

This work is part of our current project to create a biomechanically realistic human hand model to better understand what features are most important to mimic in the designs of robotic hands. Such a model will also help clinicians better plan reconstructive hand surgeries.

We describe our publicly available grasping simulator and review experiments performed with it. The paper demonstrates the usefulness of this system as a tool for grasping research.

This paper aims to enable the robot to obtain human-like compliant manipulation skills for the peg-in-hole (PiH) assembly task by learning from demonstration.

A modified dynamic movement primitives (DMPs) model with a novel hybrid force/position feedback in Cartesian space for the robotic PiH problem is proposed by learning from demonstration. To ensure a compliant interaction during the PiH insertion process, a Cartesian impedance control approach is used to track the trajectory generated by the modified DMPs.

The modified DMPs allow the robot to imitate the trajectory of demonstration efficiently and to generate a smoother trajectory. By taking advantage of force feedback, the robot shows compliant behavior and could adjust its pose actively to avoid a jam. This feedback mechanism significantly improves the dynamic performance of the interactive process. Both the simulation and the PiH experimental results show the feasibility and effectiveness of the proposed model.

The trajectory and the compliant manipulation skill of the human operator can be learned simultaneously by the new model. This method adopted a modified DMPs model in Cartesian space to generate a trajectory with a lower speed at the beginning of the motion, which can reduce the magnitude of the contact force.

During the design of a new product, the generation of assembly sequences plans (ASPs) has become one of the most important problems taken into account by researchers. In fact, a good mounting order allows the time decrease of the assembly process which leads to the reduction of production costs. In this context, researchers developed several methods to generate and optimize ASP based on various criteria. Although this paper aims to improve the quality of ASP it is necessary to increase the number of criteria which must be taken into account when generating ASPs.

In this paper, an ASP generation approach, which is based on three main algorithms, is proposed. The first one generates a set of assembly sequences based on stability criteria. The obtained results are treated by the second algorithm which is based on assembly tools (ATs) workspace criterion. An illustrative example is used to explain the different steps of this proposed approach. Moreover, a comparative study is done to highlight its advantages.

The proposed algorithm verifies, for each assembly sequence, the minimal required workspace of used AT and eliminates the ASPs non-respecting this criterion. Finally, the remaining assembly sequences are treated by the third algorithm to reduce the AT change during the mounting operation.

The proposed approach introduces the concept of AT workspace to simulate and select ASPs that respect this criterion. The dynamic interference process allows the eventual collision detection between tool and component and avoids it. The proposed approach reduces the AT change during the mounting operations.

The application of robots to industrial problems often requires grasping and manipulation of the work piece. The robot is able to perform a task adequately only when it is assigned proper tooling and adequate methods of grasping and handling work pieces. The design of such a task requires an in‐depth knowledge of several interrelated subjects including: gripper design, force, position, stiffness and compliance control and grasp configurations. In this paper, we review the research finding on these subjects in order to present in a concise manner, which can be easily accessed by the designers of robot task, the information reported by the researchers, and identify based on the review, future research directions in these areas.

The purpose of this paper is to propose a method to avoid hyperstaticity and eventually reduce the magnitude of undesired force/torques. The authors also study the influence of hyperstaticity on human motor control during a redundant task.

Increasing the level of transparency of robotic interfaces is critical to haptic investigations and applications. This issue is particularly important to robotic structures that mimic the human counterpart's morphology and attach directly to the limb. Problems arise for complex joints such as the wrist, which cannot be accurately matched with a traditional mechanical joint. In such cases, mechanical differences between human and robotic joint cause hyperstaticity (i.e. over-constrained) which, coupled with kinematic misalignment, leads to uncontrolled force/torque at the joint. This paper focusses on the prono-supination (PS) degree of freedom of the forearm. The overall force and torque in the wrist PS rotation is quantified by means of a wrist robot.

A practical solution to avoid hyperstaticity and reduce the level of undesired force/torque in the wrist is presented. This technique is shown to reduce 75 percent of the force and 68 percent of the torque. It is also shown an over-constrained mechanism could alter human motor strategies.

The presented solution could be taken into account in the early phase of design of robots. It could also be applied to modify the fixation points of commercial robots in order to reduce the magnitude of reaction forces and avoid changes in motor strategy during the robotic therapy.

In this paper for the first time the authors study the effect of hyperstaticity on both reaction forces and human motor strategies.

The purpose of this paper is to address optimal positioning of a group of mobile robots for a successful manipulation and transportation of payloads of any shape.

The chosen methodology to achieve optimal positioning of the robots around the payload to lift it and to transport it while maintaining a geometric multi-robot formation is presented. This appropriate configuration of the set of robots is obtained by combining constraints ensuring stable and safe lifting and transport of the payload. A suitable control law is then used to track a virtual structure in which each elementary robot has to keep its desired position with respect to the payload.

An optimal positioning of mobile robots around a payload to ensure stable co-manipulation and transportation task according to stability multi-criteria constraints. Simulation and experimental results validate the proposed control architecture and strategy for a successful transportation task based on virtual structure navigation approach.

This paper presents a new strategy for co-manipulation and co-transportation task based on a virtual structure navigation approach. An algorithm for optimal positioning of mobile robots around a payload of any mass and shape is proposed while ensuring stability during the whole process by respecting multi-criteria task stability constraints.

Purpose – The aim of this study is to examine the impact of co-operative governance structures on citizen participation in public service provision.Methodology – Using a multiple case study-approach, we analyse and compare five examples of co-operative public–citizen partnerships in Austria and Germany.Findings – The study clearly shows that co-operatives can be a tool for both, (1) the bottom-up self-organization of citizens (co-operative as ‘contested space’) and (2) the top-down organization to canalize citizen participation (co-operative as ‘invited space’). Co-operative public–citizen partnerships therefore represent a balancing act between dependency through public funding and autonomy through community-based decision making.Research implications and limitations – The chapter underlines the importance of context-sensitive qualitative research. Limitations might stem from the fact that municipal areas might differ in other countries than Germany and Austria, for example, due to legal prerequisites.Practical implications – If regional government representatives are supporting a bottom-up initiative, they are more inclined to provide crucial resources for the public–citizen partnership and tensions between different stakeholders involved are weakened.Social implications – Co-operative public–citizen partnerships might enhance participatory democracy and seem to strengthen solidarity and social cohesion on the neighbourhood level.Originality/value of chapter – In showing that co-operatives are a suitable governance structure for community organizations, which enhance democratic decision making and foster social innovation in public service delivery, we support the findings of other studies. The chapter suggests that in order to enhance our understanding of citizen participation, context-sensitive research that goes beyond merely descriptive governance analysis is needed, taking into account the historical trajectories of public–citizen partnerships.