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This article presents a fuzzy system-based modeling approach to estimate the weld bead geometry (WBG) from the welding process variables (WPVs) and to achieve a specific weld bead shape. The bacterial memetic algorithm (BMA) is applied to solve these problems in two different roles, as a supervised trainer, and as an optimizer. As a supervised trainer, the BMA is applied to tune two different WBG models. The bead geometry properties (BGP) model follows a traditional approach providing the WBG properties as outputs. The direct profile measurement (DPM) model describes the bead profiles points by a non-linear function realized in the form of fuzzy rules. As an optimizer, the BMA utilizes the developed fuzzy systems to find the solution sets of WPVs to acquire the desired WBG. The best performance is achieved by applying six rules in the BGP model and eleven rules in the DPM model. The results indicate that the normalized root means square error for the validation data set lies in the range of 0.40 - 1.56% for the BGP model and 4.49 - 7.52% for the DPM model. The comparative analysis suggests that the BGP model estimates the BWG in a superior manner when several WPVs are altered. The developed fuzzy systems provide a tool for interpreting the effects of the WPVs. The developed optimizer provides multiple valid set of WPVs to produce the desired WBG, thus supporting the selection of those process variables in applications.

In this paper, the use of a monitoring companion is proposed to more efficiently collect the process information during the tuning of industrial systems, and therefore to assist the system integrator in the optimization process for complex robotic installations. The monitoring companion consists of an industrial manipulator (monitoring robot) and a Unity-ROS framework for controlling it. We discuss in this paper the features that allow the solution to be re-used in different industrial application thanks to its compatibility with ROS. In particular, we present the approach based on admittance virtual fixtures and how we use such abstraction to track a moving target (it could be the end-effector of another robot for example). Moreover, the concept of varying compliance is introduced as a way to influence the motion of the monitoring robot on the virtual fixtures in the presence of obstacles. The experiments have been conducted in simulation as well as on real hardware to test the accuracy of the system at respecting the virtual fixtures with both a static and a moving monitoring target, although in the current implementation the varying compliance was not included in the experiments.

Published version at http://dx.doi.org/10.17667/riim.2018.1/1 Laboratory is a key element of engineering and applied sciences educational systems. With the development of Internet and connecting IT technologies, the appearance of remote laboratories was inevitable. Virtual laboratories are also available; they place the experiment in a simulated environment. However, this writing focuses on remote experiments not virtual ones. From the students’ point of view, it is a great help not only for those enrolling in distant or online courses but also for those studying in a more traditional way. With the spread of smart, portable devices capable of connection to the internet, students can expand or restructure time spent on studying. This is a huge help to them and also allows them to individually divide their time up, to learn how to self-study. This independent approach can prepare them for working environments. It offers flexibility and convenience to the students. From the universities’ point of view, it helps reduce maintenance costs and universities can share experiments which also helps the not so well-resourced educational facilities.

Planning and monitoring the manufacturing of high quality one-of-a-kind products are challenging tasks. In the implementation of an industrial system, the commissioning phase is typically comprised of a programming phase and an optimization phase. Most of the resources are commonly invested in the optimization of the process. The time and cost of the implementation can be reduced if the monitoring system is not embedded in the industrial process, but kept instead as a decoupled task. In this paper we present a framework to simulate and execute the monitoring task of an industrial process in Unity3D, without interfering with the original system. The monitoring system is made of external additional equipment and is decoupled from the industrial task. The monitoring robot's path is subject to multiple constraints to track the original process without affecting its execution. Moreover, the framework is flexible thanks to the Unity-ROS communication so that the monitoring task can be carried on by any ROS-compatible device. The monitoring system has been applied to a robotic system for heavy, multi-pass TIG welding of voluminous work-pieces. The results of the implementation show that the constraints for monitoring were satisfactory in the 3D environment and capable for real robot application.

The recent progress made in the field of Augmented Reality/Mixed Reality (AR/MR) has opened new possibilities and approaches to research areas that can benefit from 3D visualization of digital content in the real world. In fact, human-robot interaction design and the design of user interfaces have very much to gain from MR technologies. Nonetheless, designing the user-robot interaction and processing multimodal feedbacks are very challenging tasks. In this paper we focus in particular on interactions in mixed reality. The main contribution of this paper is the implementation of a control system for an industrial manipulator through the user's interactions with MR content displayed with the Microsoft HoloLens. The system is based on the communication between Unity3D (used to design the user experience) and ROS, therefore extendible to any ROS-compatible robotic hardware.

Worldwide, the focus on industrial development is on achieving smaller and smaller batch sizes in production. This has led to the need for providing cost efficient support to robot users. In this study, a new method for the remote operation of industrial robot systems is introduced. The method is based upon multi-modal man-machine communication and sensor bridging to transfer huge amounts of information from the industrial robot cell to the brain of the remote operator.

In an increasing demand for human-robot collaboration systems, the need for safe robots is crucial. This paper presents a proactive strategy to enable an awareness of the current risk for the robot. The awareness is based upon a map of historically occupied space by the operator. The map is built based on a risk evaluation of each pose presented by the operator. The risk evaluation results in a risk field that can be used to evaluate the risk of a collaborative task. Based on this risk field, a control algorithm that constantly reduces the current risk within its task constraints was developed. Kinematic redundancy was exploited for simultaneous task performance within task constraints, and risk minimization. Sphere-based geometric models were used both for the human and robot. The strategy was tested in simulation, and implemented and experimentally tested on a NACHI MR20 7-axes industrial robot.

Using robots for heavy welding application is a growing field of automation; numerous development project carried out for the ship manufacturing or the offshore industry. However, most of the largest size Francis hydro power turbine are still welded manually due to their unique and complex design, and the high-quality requirements. This paper presents an application of a Tungsten Inner Gas robot welding system for heavy multi-pass welding, what emphasizes the synergy of advanced CAD — CAM programming and human-in-the-loop control. The concept consists three separated phase: the off-line planning of the whole process, the plan update based on the previous activities, and the on-line welding operation. The proposed system was verified through experiments.

The installation of industrial robot systems requires considerable human effort both related to the mechanical and electromechanical setup. However, the task of programming a robot is of particular importance to satisfy given process requirements. Typically, only 20% of the entire programming time is needed to define the path and logics while the remaining 80% is related to process optimization. This causes considerable costs due to the need for human presence. With a remote assistance system and a process monitoring robot, expert assistance could be decoupled from the physical presence. An important challenge is to solve the tracking between the monitoring robot and the robot performing the process. In this paper we propose a controllable sensor system for enhanced process monitoring. The system is decoupled from the process tool and can therefore be controlled independently. It provides the machine operator with adaptive process information and enhances the capabilities to qualify complex processes. We apply the concept to an autonomous sensor robot monitoring an industrial robot system for heavy, multipass TIG welding of voluminous workpieces.

Recently industrial robot systems are introduced widely even in the small and medium size enterprises. However, it is difficult for them to employ professional engineers permanently. Then, they need to depend on outside to maintain industrial robots. Therefore a remote operation support system for industrial robots is proposed. Visual and auditory feedback is often used. However, a perception of the information might be limited if different kinds of information in particular sense modality is delivered at the same time. To solve the problem, we proposed a tactile interface which uses tactile information. This paper evaluates the usefulness of the vibrotactile information using the glove-type interface. The experimental results showed that vibrotactile information could not improve work efficiency. However it enable an operator to concentrate other information without increasing a workload. Therefore vibrotactile information is useful.

In this paper a novel concept of human-robot interaction (HRI) modeling is proposed. Including factors like trust in automation, situational awareness, expertise and expectations a new user experience framework is formed for industrial robots. Service Oriented Robot Operation, proposed in a previous paper, creates an abstract level in HRI and it is also included in the framework. This concept is evaluated with exhaustive tests. Results prove that significant improvement in task execution may be achieved and the new system is more usable for operators with less experience with robotics; personnel specific for small and medium enterprises (SMEs).

The trend in robotization is to use industrial robot more and more frequently in small and medium sized enterprises (SMEs). Wide spread of the enterprises over considerable area and small number of applied robot units per enterprise, emerges need to provide an efficient, inexpensive and immediate support remotely. Since there are a lot of important information to be communicated to efficiently support an industrial robot system, traditional data acquisition and human-machine-interfaces (HMI) cannot provide complete and effectively comprehended overview of the state of the robot cell. The goal of the paper is to demonstrate new methodology and technology for remote HMI based upon Cognitive Informatics Communication (CogInfoCom 2011) that augments efficiency of communication between an industrial robot system and remote operator exercising control over the system. For the purposes of evaluation a remote operating laboratory is developed. The laboratory consists of multimodal HMI interfacing an operator with physically separated seven axes NACHI MR20 robot. By means of multi-camera vision, multi-speaker sound system, and advanced 3D simulation, the robot is controlled remotely. The results show that HMI based upon CogInfoCom can be beneficially applied to communicate complex states of an industrial robot system to a remote operator.

This paper presents a robot control system using force control on a redundant industrial robot. The control system is based upon an active force feedback system using six axes force sensor attached to the robot's end effector. The redundancy is used to explore a model for singularity avoidance based on different states of redundancy. The system is implemented and tested experimentally for one of the described states on a NACHI MR20 seven axes robot. The experimental results demonstrate the possibility to control a redundant industrial robot by force control.

This paper presents an automated assembly and tack welding operation of high performance aerospace components using two real-time controlled industrial robots and a high-precision non-contact measurement system. The system was able to align two components with an offset distance less than 0.1 mm, well within manufacturing tolerances.

A system concept for industrial collision avoidance is presented. The paper searches solutions for small and medium enterprises which have strictly limited resources for robot installations. Key factor is to use commercially available components and user-friendly algorithms. The experimental setup consists of a 7-axis industrial robot and an industrial robot controller. The obstacle detecting sensors are applied on the robotic arm. Designing guidelines are formed according to industrial considerations and preliminary experiments are presented.

This paper evaluates a wristband-type tactile interface as a user interface for controlling an industrial robot remotely. When operating a remote monitoring system, information delivery from a local site to an operator at a remote site is important. Visual and auditory feedback is often used. However, perception of the information might be limited if different kinds of information in particular sense modality is delivered at the same time. To solve the problem, we proposed a tactile interface which uses tactile information and we evaluate it. First, we explain the remote operation system for industrial robot and interface, then after that, we present an experiment of vibrotactile information of industrial robot.

The global industry is developing towards smaller and smaller batch sizes in production due to the high pressure on Just-in-time production. This has led to the need for providing cost efficient support to robot users, especially SMEs having limited internal resources and competence to setup, maintain and reconfigure their industrial robot systems. In this study, a new method for the remote operation of industrial robot systems is presented. The method is based upon multi-modal man-machine communication and sensor bridging to transfer huge amounts of information from the industrial robot cell to the brain of the remote operator. The general methodology is explained, however, a special focus is put on gripping and stick-slip detecting in order to provide optimal grasping conditions during robot operations; especially during remote operation.

Development of the international industry is towards smaller and smaller batch sizes in the production. This has riced a need for cost efficient support of robot users. In this paper, new methodology for remote operation of industrial robot systems is introduced. The method is based upon multi-modal man-machine communication and sensor bridging to transfer the huge amount of information from the industrial robot cell to the brain of the remote operator.

Presents a robot control system dedicated to grinding large Francis turbines. The control system is based on an active force feedback system using a three‐axes force sensor attached to the robot’s end effector. This system offers high flexibility and robustness against workpiece positioning and grinding tool wear. It provides control of the grinding process parameters ensuring high productivity in addition to good grinding performance and grinding tool economy. The system was experimentally tested out on a MultiCraft 560 grinding robot.

We investigated the correspondence relationship between vibrotactile stimuli and tactile mental imagery using a vibrotactile glove proposed in a previous study as an interface for vibrotactile stimuli [1]. The mental impressions of the vibrotactile stimuli obtained by the human subjects were measured using the semantic differential method. Analysis of variance, multiple comparisons, and factor analyses were used to extract and evaluate the distinctive imageries induced by passive touch, based on the answers of the subjects to certain questions. To build a cognitive model of tactile sensations, we investigated the correspondence relationships between tactile sensations and vibrotactile stimuli.

In this paper the main focus is on the user interfaces available for robot controllers and how they comply with the requirements of flexibility. An overview is given of the most important robot manufacturers teach pendant interfaces. The conclusion is that the process of creating customized user interfaces is still complicated and the how-to is unclear. We introduce the concept of flexible user interface based on service oriented robot cell operation. In order to offer more user friendly solutions industrial robot systems should use human-centred approach. Service oriented robot cell operation creates an abstract level for human robot interaction which is adapted to human cognition. A flexible graphical user interface is the final link between the robot cell and the operator, which offers a solution for issues faced in creation of customized user interfaces by its flexibility. One implementation called FlexGui is described in details and the most important features are demonstrated in a case study.