scholarly journals Adaptive Motion Control Middleware for Teleoperation Based on Pose Tracking and Trajectory Planning

Author(s):  
Andreas Blank ◽  
Engin Karlidag ◽  
Lukas Zikeli ◽  
Maximilian Metzner ◽  
Jörg Franke

AbstractConcurrent with autonomous robots, teleoperation gains importance in industrial applications. This includes human–robot cooperation during complex or harmful operations and remote intervention. A key role in teleoperation is the ability to translate operator inputs to robot movements. Therefore, providing different motion control types is a decisive aspect due to the variety of tasks to be expected. For a wide range of use-cases, a high degree of interoperability to a variety of robot systems is required. In addition, the control input should support up-to-date Human Machine Interfaces. To address the existing challenges, we present a middleware for teleoperation of industrial robots, which is adaptive regarding motion control types. Thereby the middleware relies on an open-source, robot meta-operating system and a standardized communication. Evaluation is performed within defined tasks utilizing different articulated robots, whereby performance and determinacy are quantified. An implementation sample of the method is available on: https://github.com/FAU-FAPS/adaptive_motion_control.

Author(s):  
Gregor Lux ◽  
Marco Ulrich ◽  
Thomas Baker ◽  
Martin Hutterer ◽  
Gunther Reinhart

Purpose Articulated robots are widely used in industrial applications owing to their high repeatability accuracy. In terms of new applications such as robot-based inspection systems, the limitation is a lack of pose accuracy. Mostly, robot calibration approaches are used for the improvement of the pose accuracy. Such approaches however require a profound understanding of the determining effects. This paper aims to provide a non-destructive analysis method for the identification and characterisation of non-geometric accuracy effects in relation to the kinematic structure for the purpose of an accuracy enhancement. Design/methodology/approach The analysis is realised by a non-destructive method for rotational, uncoupled robot axes with the use of a 3D lasertracker. For each robot axis, the lasertracker position data for multiple reflectors are merged with the joint angles given by the robot controller. Based on this, the joint characteristics are determined. Furthermore, the influence of the kinematic structure is investigated. Findings This paper analyses the influence of the kinematic structure and non-geometric effects on the pose accuracy of standard articulated robots. The provided method is shown for two different industrial robots and presented effects incorporate tilting of the robot, torsional joint stiffness, hysteresis, influence of counter balance systems, as well as wear and damage. Practical implications Based on these results, an improved robot model for a better match between the mathematical description and the real robot system can be achieved by characterising non-geometric effects. In addition, wear and damages can be identified without a disassembly of the system. Originality/value The presented method for the analysis of non-geometric effects can be used in general for rotational, uncoupled robot axes. Furthermore, the investigated accuracy influencing effects can be taken into account to realise high-accuracy applications.


2020 ◽  
Vol 44 (8) ◽  
pp. 1451-1467
Author(s):  
Alexandros Nikou ◽  
Shahab Heshmati-alamdari ◽  
Dimos V. Dimarogonas

Abstract This paper presents a scalable procedure for time-constrained planning of a class of uncertain nonlinear multi-robot systems. In particular, we consider N robotic agents operating in a workspace which contains regions of interest (RoI), in which atomic propositions for each robot are assigned. The main goal is to design decentralized and robust control laws so that each robot meets an individual high-level specification given as a metric interval temporal logic (MITL), while using only local information based on a limited sensing radius. Furthermore, the robots need to fulfill certain desired transient constraints such as collision avoidance between them. The controllers, which guarantee the transition between regions, consist of two terms: a nominal control input, which is computed online and is the solution of a decentralized finite-horizon optimal control problem (DFHOCP); and an additive state feedback law which is computed offline and guarantees that the real trajectories of the system will belong to a hyper-tube centered along the nominal trajectory. The controllers serve as actions for the individual weighted transition system (WTS) of each robot, and the time duration required for the transition between regions is modeled by a weight. The DFHOCP is solved at every sampling time by each robot and then necessary information is exchanged between neighboring robots. The proposed approach is scalable since it does not require a product computation among the WTS of the robots. The proposed framework is experimentally tested and the results show that the proposed framework is promising for solving real-life robotic as well as industrial applications.


Sensors ◽  
2018 ◽  
Vol 19 (1) ◽  
pp. 17 ◽  
Author(s):  
Oliver Kosak ◽  
Constantin Wanninger ◽  
Alwin Hoffmann ◽  
Hella Ponsar ◽  
Wolfgang Reif

Mobile multirobot systems play an increasing role in many disciplines. Their capabilities can be used, e.g., to transport workpieces in industrial applications or to support operational forces in search and rescue scenarios, among many others. Depending on the respective application, the hardware design and accompanying software of mobile robots are of various forms, especially for integrating different sensors and actuators. Concerning this design, robots of one system compared to each other can be classified to exclusively be either homogeneous or heterogeneous, both resulting in different system properties. While homogeneously configured systems are known to be robust against failures through redundancy but are highly specialized for specific use cases, heterogeneously designed systems can be used for a broad range of applications but suffer from their specialization, i.e., they can only hardly compensate for the failure of one specialist. Up to now, there has been no known approach aiming to unify the benefits of both these types of system. In this paper, we present our approach to filling this gap by introducing a reference architecture for mobile robots that defines the interplay of all necessary technologies for achieving this goal. We introduce the class of robot systems implementing this architecture as multipotent systems that bring together the benefits of both system classes, enabling homogeneously designed robots to become heterogeneous specialists at runtime. When many of these robots work together, we call the structure of this cooperation an ensemble. To achieve multipotent ensembles, we also integrate reconfigurable and self-descriptive hardware (i.e., sensors and actuators) in this architecture, which can be freely combined to change the capabilities of robots at runtime. Because typically a high degree of autonomy in such systems is a prerequisite for their practical usage, we also present the integration of necessary mechanisms and algorithms for achieving the systems’ multipotency. We already achieved the first results with robots implementing our approach of multipotent systems in real-world experiments as well as in a simulation environment, which we present in this paper.


Author(s):  
Kejie Gong ◽  
Ying Liao ◽  
Yafei Mei

This article proposed an extended state observer (ESO)–based output feedback control scheme for rigid spacecraft pose tracking without velocity feedback, which accounts for inertial uncertainties, external disturbances, and control input constraints. In this research, the 6-DOF tracking error dynamics is described by the exponential coordinates on SE(3). A novel continuous finite-time ESO is proposed to estimate the velocity information and the compound disturbance, and the estimations are utilized in the control law design. The ESO ensures a finite-time uniform ultimately bounded stability of the observation states, which is proved utilizing the homogeneity method. A non-singular finite-time terminal sliding mode controller based on super-twisting technology is proposed, which would drive spacecraft tracking the desired states. The other two observer-based controllers are also proposed for comparison. The superiorities of the proposed control scheme are demonstrated by theory analyses and numerical simulations.


IEEE Access ◽  
2021 ◽  
pp. 1-1
Author(s):  
Alejandro GutierreznGiles ◽  
Luis U. EvangelistanHernandez ◽  
Marco A. Arteaga ◽  
Carlos A. CruznVillar ◽  
Alejandro RodrigueznAngeles

2017 ◽  
Vol 107 (09) ◽  
pp. 594-599
Author(s):  
A. Magaña ◽  
G. Prof. Reinhart

Industrieroboter sind zu einer Schlüsseltechnologie in der Produktion geworden. Mit dem steigenden Einsatz von diversen Robotersystemen wächst das Bedürfnis, deren Kompatibilität zu steigern. Heutzutage gibt es keine Technologie in der Industrie, die eine standardisierte Programmierung und Steuerung von verschiedenen Robotersystemen gewährleisten kann. Dieser Fachbeitrag präsentiert ein einheitliches Konzept, welches die Anwendung von herstellerneutralen Roboterapplikationen ermöglicht.   Industrial robots have become a key technology in production. The increasing use of various robotic systems, raises the need to enhance their compatibilit.y Nowadays, there is no technology in the industry to guarantee a standardized programming and control of different robot systems. This article presents a concept enabling the use of manufacturer-independent robot applications.


Author(s):  
Muhammed Oguz Tas ◽  
Ugur Yayan ◽  
Hasan Serhan Yavuz ◽  
Ahmet Yazici

Robotic systems are used many areas where it is dangerous or difficult for people to do. The importance of autonomous robots increased with the Industry 4.0, and the concept of reliability needed more attention for long term operability of robotic systems. In this study, reliability based task allocation analysis is performed for robots by using fuzzy logic. With the help of fuzzy inference system, the result of reliability based task allocation are obtained using the amount of carried load and load carrying distances. In the study, cases of task allocation based on nearest and reliability were analyzed and compared. Experimental results showed that, the system reliability that occurs with reliability based task allocation is higher than the system reliability that occurs with nearest based task allocation.


2013 ◽  
Vol 433-435 ◽  
pp. 117-120
Author(s):  
Fei Tao ◽  
Ping An Mu ◽  
Shu Guang Dai

This paper puts forward a method to control the industrial robots based on the NI Corporations LabVIEW virtual instrument technology. By designing the communication protocol between the LabVIEW software program on PC and industrial robots, the LabVIEW program can take the control of industrial robots by using RS232 serial ports, including the operation instructions' transmission, the feedback of the robots' running, and the data exchange between the two. The result shows that can effectively realize the motion control of industrial robots based on LabVIEW.


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