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The purpose of the paper is to propose an efficient and accurate force/torque (F/T) sensing method for the robotic wrist-mounted six-dimensional F/T sensor based on an excitation trajectory.

This paper presents an efficient and accurate F/T sensing method based on an excitation trajectory. First, the dynamic identification model is established by comprehensively considering inertial forces/torques, sensor zero-drift values, robot base inclination errors and forces/torques caused by load gravity. Therefore, the sensing accuracy is improved. Then, the excitation trajectory with optimized poses is used for robot following and data acquisition. The data acquisition is not limited by poses and its time can be significantly shortened. Finally, the least squares method is used to identify parameters and sense contact forces/torques.

Experiments have been carried out on the self-developed robot manipulator. The results strongly demonstrate that the proposed approach is more efficient and accurate than the existing widely-adopted method. Furthermore, the data acquisition time can be shortened from more than 60 s to 3 s/20 s. Thus, the proposed approach is effective and suitable for fast-paced industrial applications.

The main contributions of this paper are as follows: the dynamic identification model is established by comprehensively considering inertial forces/torques, sensor zero-drift values, robot base inclination errors and forces/torques caused by load gravity; and the excitation trajectory with optimized poses is used for robot following and data acquisition.

Reviews the benefits and potential application of tactile sensors for use with robots.

Includes the most recent advances in both the design/manufacturing of various tactile sensors and their applications in different industries. Although these types of sensors have been adopted in a considerable number of areas, the applications such as, medical, agricultural/livestock and food, grippers/manipulators design, prosthetic, and environmental studies have gained more popularity and are presented in this paper.

Robots can perform very useful and repetitive tasks in controlled environments. However, when the robots are required to handle the unstructured and changing environments, there is a need for more elaborate means to improve their performance. In this scenario, tactile sensors can play a major role. In the unstructured environments, the robots must be able to grasp objects (or tissues, in the case of medical robots) and move objects from one location to another.

In this work, the emphasis was on the most interesting and fast developing areas of the tactile sensors applications, including, medical, agriculture and food, grippers and manipulators design, prosthetic, and environmental studies.

Force/torque sensing is very important for several automatic and industrial robotic applications. Basically, if precise control of the forces that arise from contact between tools and parts is required to successfully complete the automatic task, then a force/torque sensor is needed along with some force/torque control technique. In this paper we focus on force/torque sensing aspects applied to industrial robotic tasks. Concentrating on a particular type of force/torque sensor, we demonstrate how to use them and how to integrate them into force/torque control applications using robots. Finally, an industrial application is presented where force control was fundamental for the success of the task.

When designing hardware and algorithms for robotic manipulation and grasping, sensory information is typically needed to control the grasping process. This paper presents an overview of the major grasping and manipulation approaches and the more common hardware used to obtain the necessary sensory information.

This paper presents an overview of tactile sensing in intelligent robotic manipulation. The history, the common issues, and applications are reviewed. Sensor performance is briefly discussed and compared to the human tactile sense. Advantages and disadvantages of the most common sensor approaches are discussed. Some examples are given of sensors that are widely available as of today. Eventually, some examples of the state‐of‐the‐art in tactile sensing application are presented.

Although many sensor technologies and strong theoretical models have been developed, there is still much left to be done in intelligent grasping and manipulation. This is partly due to the youth of the field and the complex nature of safe control in uncertain environments. Even though there are impressive results when it comes to specific examples of advanced manipulation, there seems to be room for great improvements of hardware and especially algorithms when it comes to more generic everyday domestic tasks.

This paper presents a review of sensor hardware while also giving a glimpse of the major topics in grasping and manipulation. While better hardware of course is desirable, the major challenges seem to lie in the development and application of grasping and manipulation algorithms.

Presents an on‐line calibration methodology for robot relative positioning inaccuracy. This methodology eliminates the need for time‐consuming off‐line calibrations relying on accurate models and complicated procedures. To realize this methodology, a vision system, a 3D force/torque sensor, and control strategies involving Neural Networks (NNs) were incorporated with an industrial robot.

The main objective of this paper is to report the development of an indirect force control strategy designed to operate with industrial robotic deburring applications. More specifically, the system reported here is developed to debur high‐quality knives that incorporate innovative design from well‐known authors (fashion designers). Therefore, these products are very difficult to manufacture and have quality requirements incompatible with human‐based deburring, since humans introduce too many unacceptable deviations as a consequence of their incapacity to maintain concentration for long periods of time.

Since a good model of the environment is difficult to obtain, namely on industrial applications, a simple strategy was designed to obtain the relevant parameters leading to an acceptable performance. Consequently, the system implements an indirect force control strategy as a way to use actual robot controllers, explore the computing power of external personal computers, and the advanced features of modern force‐torque sensors. The proposed strategy is presented in some detail and further discussed using a few test‐case experiments.

Experiments show a usable setup for contour following which is very useful to obtain the work‐piece profile. A good selection of the path step seems to be, as expected, one of the most important variables to achieve good results: the smaller the increment over the trajectory the more regular is the resulting force profile. Low speeds also seem to lead to better results. The strategy implemented to maintain contact with the object and keep contact force at a certain level seems to result over surfaces with a smooth and large radius continuity, although there are significant force variations on impact with objects (which is not important since impacts can be planned), especially at the higher speeds, and even more significant near object edges. The desired contact force is also a parameter that should be tested. In the presented experiments, a contact force of 10 N was selected and oscillations of 1 N were observed around this value. In an industrial environment, more exposed to noise and vibrations, a higher contact force may be required. On the other hand, the increase of the contact force also increases the flexion of the sensing tool what brings more uncertainty to the calculated contact point. Large force oscillations imply more uncertainty of the obtained work‐piece contour. Like in any industrial process selected parameters are the ones that show acceptable results at higher execution speeds.

The objective of the presented setup is to find the better compromise for a particular industrial application, achieving acceptable operational cycle times.

The obtained results are encouraging and the ability to perform contour recognition under a specified contact force can be very useful with the automatic deburring system being developed. In fact, this feature enables the system to acquire the exact contour of the working piece in the exact same conditions that will be used for the subsequent deburring task. This will contribute to minimize error and increase the process speed.

An extensive survey of over 300 reports worldwide shows that the state‐of‐the‐art in tactile sensing — defined as continuously variable touch sensing over an area where there is special resolution — is primitive. Only now is a new level of sophistication beginning to appear. However, for industrial systems the simplest may prove to be the most reliable.

This paper recommends an improved design methodology for the slave half of teleoperator systems based on the notion of master‐slave symmetry. Traditional slaves consist of a conventional robot retrofitted with force‐torque sensors. The new methodology eliminates dependence on destabilizing force‐torque‐sensor schemes by augmenting existing master design methods with newly invented cable mechanisms. Design goals such as bandwidth, backdrivability, and force fidelity have been applied successfully to optimize design of the trajectory‐and‐force‐controllable Whole‐Arm Manipulation (WAM) robot. Although not yet used as the slave of a teleoperator system, the results from performance tests of the experimental WAM manipulator are promising. Finally, the authors suggest a new concept ‐ Whole‐Arm Haptics ‐ that is only possible with whole‐arm manipulation, where the user steers the kinematic redundancy directly. Whole‐Arm Haptics allow teleoperators to manipulate objects larger than the slave itself.

Installing a tight tolerant stepped shaft is not a trivial task for an industrial robot. If all peg-hole constraints are complete, the cascaded peg-in-hole task can be simplified into several independent stages and accomplished one by one. However, if some of the constraints are incomplete, the cross stage interference will bring additional difficulties. This paper aims to discuss the cascaded peg-in-hole problem with incomplete constraints.

In this paper, the problem is formulated according to geometric parameters of the stepped shaft and completeness of the corresponding hole. The possible jamming type is modeled and analyzed. A contact modeling and control strategy is proposed to compensate the peg postures under incomplete constraints.

The above methods are implemented on an experiment platform and the results verify the effectiveness of the proposed robotic assembly strategy.

Based on force/torque sensor, a hybrid control strategy for incomplete constraints cascaded peg-in-hole assembly problem is proposed.

The paper seeks to present a new generation of torque‐controlled light‐weight robots (LWR) developed at the Institute of Robotics and Mechatronics of the German Aerospace Center.

An integrated mechatronic design approach for LWR is presented. Owing to the partially unknown properties of the environment, robustness of planning and control with respect to environmental variations is crucial. Robustness is achieved in this context through sensor redundancy and passivity‐based control. In the DLR root concept, joint torque sensing plays a central role.

In order to act in unstructured environments and interact with humans, the robots have design features and control/software functionalities which distinguish them from classical robots, such as: load‐to‐weight ratio of 1:1, torque sensing in the joints, active vibration damping, sensitive collision detection, compliant control on joint and Cartesian level.

The DLR robots are excellent research platforms for experimentation of advanced robotics algorithms. Space and medical robotics are further areas for which these robots were designed and hopefully will be applied within the next years. Potential industrial application fields are the fast automatic assembly as well as manufacturing activities done in cooperation with humans (industrial robot assistant). The described functionalities are of course highly relevant also for the potentially huge market of service robotics. The LWR technology was transferred to KUKA Roboter GmbH, which will bring the first arms on the market in the near future.

This paper introduces a new type of LWR with torque sensing in each joint and describes a consistent approach for using these sensors for manipulation in human environments. To the best of one's knowledge, the first systematic experimental evaluation of possible injuries during robot‐human crashes using standardized testing facilities is presented.