An Implemented of a Real-Time Experimental Setup for Robotic Teleoperation System

The development of this work presents the implementation of an experimental platform, which will permit to investigate on a methodology for the design and analysis of a teleoperated system, considering the delay in the communication channel. The project has been developed in partnership with the laboratory of Automatic and Robotics of the Universidad Politécnica de Madrid and the Laboratory at the Centro de Tecnologías Avanzadas de Manufactura at the Pontificia Universidad Católica del Perú. The mechanical structure of the arm that is located in the remote side has been built and the electric servomechanism has been mounted to control their movement. The experimental test of the Teleoperation system has been developed. The PC104 card commands the power interface and sensors of the DC motor of each articulation of the arm. Has developed the drives for the management of the operations of the master and the slave: send/reception of position, speed, acceleration and current data through a CAN network. The programs for the interconnection through a LAN network, between the Windows Operating System and the Real-time Operating System (QNX), has been developed. The utility of the developed platform (hardware and software) has been demonstrated

Stability Analysis of Teleoperation System by State Convergence with Variable Time Delay

We propose a novel control scheme for bilateral teleoperation of n degree-of-freedom (DOF) nonlinear robotic systems with time-varying communication delay. A major contribution from this work lies in the demonstration that the structure of a state convergence algorithm can be also applied to nth-order nonlinear teleoperation systems. By choosing a Lyapunov Krasovskii functional, we show that the local-remote teleoperation system is asymptotically stable. The time delay of communication channel is assumed to be unknown and randomly time varying, but the upper bounds of the delay interval and the derivative of the delay are assumed to be known

External force estimation for telerobotics without force sensor

This paper establishes an approach to external force estimation through the use of a mathematical model and current sensing, without employing a force/torque sensor. The advantages and need for force feedback have been well established in the field of telerobotics. This paper presents the requirement for sensorless force estimation and comparative results between a force sensor and the presented approach using an industrial robot. The approach presents not only a cost effective solution but also a solution for force sensing in hazardous environments, especially ionizing radiation prone environments where the dose rates limit the use of sensing equipment. The paper also discusses the applications and advantages presented by this work in various fields

Virtual-bike emulation in a series-parallel human-powered electric bike

Combining the advantages of standard bicycles and electrified vehicles, electric bikes (e-Bikes) are promising vehicles to reduce emission and traffic. The current literature on e-Bikes ranges from works on the energy management to the vehicle control to properly govern the human-vehicle interaction. This last point is fundamental in chain-less series bikes, where the link between the human and the vehicle behavior is only given by a control law. In this work, we address this problem in a series-parallel bike. In particular, we provide an extension of the virtual-chain concept, born for series bikes, and then we improve it developing a virtual-bike framework. Experimental results are used to validate the effectiveness of the solutions, when the cyclist is actually riding the bike.Comment: Accepted for publication at the IFAC World Congress 202

Coupled Human-machine Tele-manipulation

AbstractRobots are primarily deployed for tasks which are dirty, dull, or dangerous. While the former two are already highly automated, many dangerous tasks such as explosive ordnance disposal or inspection in hazardous environments are predominantly done via tele-operation. Usually, such tasks require the manipulation of objects in a way that cannot be done reliably with automated systems. In this paper, we present a method to tele-operate the manipulator of a robot by transferring the operator's arm movement. The movement is recorded with inertial measurement units which can be sewn into clothing and need no external infrastructure like cameras or motion capture systems. The lack of intermediate user interfaces (e.g. joysticks) makes this control method very intuitive and easy to learn. We demonstrate this with two different NIST manipulation tests and as part of an integrated system for the ELROB robot competition

Bilateralno upravljanje gibanjem za apstrakciju i reprodukciju stvarne sile

In recent years, skill preservation of an expert and skill education for young technical workers have been serious issues in medical and production fields. The best way which young technical workers learn the ripe skill is that an expert teaches them. However, unfortunately, experts have lessened in these years. So, if digital skill preservation like a haptic database is attained, it may become an innovative solution of the above problem. Thus, as the fundamental technology for development of the haptic database, this paper proposes abstraction and reproduction methods on bilateral control of real world force sensation, and reconstruction of real world environment as well. In the abstraction mode, a master-slave system is composed, and the action-reaction law is attained through bilateral control. Later, based on acceleration information, the force, position and velocity of both master and slave systems are estimated and obtained. In the reconstruction mode, an environmental model is reconstructed based on the obtained data from real-world. Next, by using reproduction mode on master side, the operator would feel the force sensation from the obtained environmental model. Here, the proposed system is able to store the bilateral real-world force sensation to a sensation database. Finally, the experimental results show the validity of the proposed method.Održavanje sposobnosti iskusnih operatera i uvježbavanje novih operatera postaje sve važnijim zadatkom u medicinskim i proizvodnim primjenama. Nove operatere najbolje uvježbavaju iskusni operateri, ali njih sve više nedostaje. Inovativno rješenje toga problema može biti pohranjivanje vještina iskusnih operatera u tzv. haptičku bazu podataka. U ovome se članku za razvoj haptičke baze podataka predlažu metode apstrakcije i reprodukcije stvarne sile u bilateralnom upravljanju te metoda rekonstrukcije udaljenoga stvarnoga prostora u kojemu djeluje prateći sustav. U apstrakcijskom načinu rada uspostavlja se bilateralno upravljanje između vodećeg i pratećeg sustava uz održavanje zakona akcije i reakcije između njih. Nakon toga estimiraju se sila, brzina i pozicija vodećeg i pratećeg sustava na temelju informacije o ubrzanju. U rekonstrukcijskom načinu rada rekonstruira se model udaljenoga stvarnoga prostora na osnovi podataka iz stvarnoga udaljenoga prostora. Na koncu, primjenom reprodukcijskog načina rada na strani vodećeg sustava operater bi trebao osjećati silu iz modela udaljenog prostora izgrađenog u rekonstrukcijskom načinu rada. Predloženi sustav omogućuje spremanje bilateralno prenošene sile u bazu podataka, što je potkrijepljeno eksperimentalnim rezultatima

Robot assisted training for upper limbs using impedance control based on iterative learning

This paper proposes an approach to improve robot assisted physical training subject to human uncertainties. This approach is based on impedance control which is used to regulate the dynamic relationship between the robot’s position and contact force. Repetitive exercise is considered and impedance parameters are adapted in accordance with the human user to provide physical training as needed. Different from the existing approaches, the proposed one has the capacity to deal with time-length-varying cycles, which is a critical issue in physical training of human’s upper limbs. By theoretical analysis and experimental results, we show that the approach can effectively learn the required robot’s impedance parameters and improve the performance of physical training

Bayesian online changepoint detection to improve transparency in human-machine interaction systems

金沢大学理工研究域電子情報学系This paper discusses a way to improve transparency in human-machine interaction systems when no force sensors are available for both the human and the machine. In most cases, position-error based control with fixed proportional-derivative (PD) controllers provides poor transparency. We resolve this issue by utilizing a gain switching method, switching them to be high or low values in response to estimated force changes at the slave environment. Since the slave-environment forces change abruptly in real time, it is difficult to set the precise value of the threshold for these gain switching decisions. Moreover, the threshold value has to be observed and tuned in advance to utilize the gain switching approach. Thus, we adopt Bayesian online changepoint detection to detect the abrupt slave environment change. This changepoint detection is based on the Bayes\u27 theorem which is typically used in probability and statistics applications to generate the posterior distribution of unknown parameters given both data and prior distribution. We then show experimental results which demonstrate the Bayesian online changepoint detection has the ability to discriminate both free motion and hard contact. Additionally, we incorporate the online changepoint detection in our proposed gain switching controller and show the superiority of our proposed controller via experiment. ©2010 IEEE

Mechanical design optimization for multi-finger haptic devices applied to virtual grasping manipulation

This paper describes the design of a modular multi-finger haptic device for virtual object manipulation. Mechanical structures are based on one module per finger and can be scaled up to three fingers. Mechanical configurations for two and three fingers are based on the use of one and two redundant axes, respectively. As demonstrated, redundant axes significantly increase workspace and prevent link collisions, which is their main asset with respect to other multi-finger haptic devices. The location of redundant axes and link dimensions have been optimized in order to guarantee a proper workspace, manipulability, force capability, and inertia for the device. The mechanical haptic device design and a thimble adaptable to different finger sizes have also been developed for virtual object manipulation