Suraj Nair

Joint-action for humans and industrial robots for assembly tasks

This paper presents a concept of a smart working environment designed to allow true joint-actions of humans and industrial robots. The proposed system perceives its environment with multiple sensor modalities and acts in it with an industrial robot manipulator to assemble capital goods together with a human worker. In combination with the reactive behavior of the robot, safe collaboration between the human and the robot is possible. Furthermore, the system anticipates human behavior, based on knowledge databases and decision processes, ensuring an effective collaboration between the human and robot. As a proof of concept, we introduce a use case where an arm is assembled and mounted on a robotpsilas body.

A Unifying Software Architecture for Model-based Visual Tracking

In this paper we propose a general, object-oriented software architecture for model-based visual tracking. The library is general purpose with respect to object model, estimated pose parameters, visual modalities employed, number of cameras and objects, and tracking methodology. The base class structure provides the necessary building blocks for implementing a wide variety of both known and novel tracking systems, integrating different visual modalities, like as color, motion, edge maps etc., in a multi-level fashion, ranging from pixel-level segmentation, up to local features matching and maximum-likelihood object pose estimation. The proposed structure allows integrating known data association algorithms for simultaneous, multiple object tracking tasks, as well as data fusion techniques for robust, multi-sensor tracking; within these contexts, parallelization of each tracking algorithm can as well be easily accomplished. Application of the proposed architecture is demonstrated through the definition and practical implementation of several tasks, all specified in terms of a self-contained description language.

The introduction of a new robot for assistance in ophthalmic surgery

This paper introduces the design and development of a new robotic system to assist surgeons performing ophthalmic surgeries. The robot itself is very compact and similar to an average human hand in size. Its primary application is intraocular micromanipulation in order to overcome the existing challenges in treatment of diseases like Retinal Vein Occlusion (RVO). The novel hybrid mechanism designed for this robot allows microscale motions and is stable in the presence of vibrations common in operation room (OR). The robotic system can be easily integrated into standard operation rooms and does not require modification of conventional surgical tools. This compact microsurgical system is suitable for mounting on the patients head and thereby, solves the problem of patient motion. The compatibility of the robotic system with a real world surgical setup was evaluated and confirmed in this work.

User friendly Matlab-toolbox for symbolic robot dynamic modeling used for control design

In this paper a new Robot Modeling/Simulation Toolbox for Matlab is presented. The primary purpose of this toolbox is to generate all the common equations required for robot control design. It can compute the kinematic and dynamic equations of a serial robot in closed-form. The toolbox generates codes for the most representative matrices of the robot dynamics. For example, the Inertia Matrix, Coriolis Matrix, Gravitational Torques Vector and most important the Robot Regressor can be computed in closed-form with symbolic representation. This toolbox uses the Denavit-Hartenberg (DH) and Euler-Lagrange Methodologies to compute the Kinematic and Dynamic models of the robot. Furthermore, it automatically generates useful code for these models, such as M-Files, Simulink model and C/C++ code, allowing easy integration with other popular Matlab toolboxes or C/C++ environments. The only requirement from the user are the DH parameters, making it an easy to use tool. For 3D visualization, the toolbox supports different methods. The primary contribution is the automation and simplification of the robot modeling process which is important for correct robot design and control. In addition, the easy to use GUI and simplified models allow rapid prototyping and simulation of robots and control design/validation. As a proof of concept, validation of the computed models of a real industrial robot is included, where the toolbox was used to compute all the robot models. Thereafter, using the motion equations generated by this toolbox, a Dynamic Compensation Control was designed and implemented on a Sta¨ubli TX-90 industrial robot in order to demonstrate how this toolbox simplifies the process.

Kinematics and dynamics analysis of a hybrid parallel-serial micromanipulator designed for biomedical applications

This paper presents the kinematic and dynamic analysis of a robot for 6 Degrees Of Freedom (DOF) micromanipulation. This robot is designed for performing intraocular manipulation but its application is not limited to ophthalmic surgery. The novel hybrid parallel-serial mechanism designed for this robot enables microscale motions with high stiffness and sufficient output forces. This portable robot can be easily integrated into standard biomedical environments and does not require any modification of conventional surgical tools. The contribution of this work is a novel design of a miniature micromanipulator comprising piezo actuator based parallel coupled joints which allow adjustable Remote Center of Motion (RCM). The advantages of the introduced mechanism compared to similar mechanisms are compactness, stiffness and simplicity of mathematical computation.

A multi-camera person tracking system for robotic applications in virtual reality TV studio

In this paper, an integrated multi-camera person tracking system for virtual reality television studios (VR-TV) is presented. The system robustly tracks the moderator while freely moving, sitting or walking around the studio, and the estimation result can be used in order to drive the main broadcasting camera mounted on a large robotic arm. Application of the proposed tracking system to real-time VR-TV results in an autonomous robot cameraman, able to keep the moderator inside the screen with jitter-free viewpoint adjustments, as required by the scene rendering engine.

Reducing communication-related complexity in heterogeneous networked medical systems considering non-functional requirements

Networked Medical Systems (NMS) promise better data exchange in medical infrastructures such as operating rooms in hospitals and clinics. However, the heterogeneous interfaces of medical systems and varied requirements on NMS such as real-time constraints, increase the communication complexity considering network architectures, communication protocols and software/hardware components. In this paper, a robot-assisted eye surgery is used as a clinical use case. Based on this use case and its communication types, non-functional requirements on NMS are derived. An approach for abstraction is proposed which targets at reducing the communication-related complexity in NMS. Complexity reduction in this case means that a multi-interface middleware in NMS abstracts the detailed knowledge required for implementation of different communication types such as real-time communication. The middleware architecture is divided into two main parts: Communication Abstraction Provider (CAP) and Communication Abstraction Bridge (CAB). CAP is the central component of the middleware which connects the medical systems using CABs. In this paper, the focus is on the complexity reduction of the real-time communication part. For this purpose, real-time communication protocols are investigated and evaluated for application in the CAP/CAB architecture. The result of the evaluation shows that Ethernet POWERLINK is the most suitable real-time communication protocol for the CAP/CAB architecture.

Virtual fixture control of a hybrid parallel-serial robot for assisting ophthalmic surgery: An experimental study

This paper presents the virtual fixture control methods for a hybrid parallel-serial micromanipulator, which is designed for assisting ophthalmic surgeons. Virtual fixtures are features of surgical robotic setups to improve quality of the surgery and reduces the operation risk. In the domain of ophthalmic surgery lack of virtual fixtures in manual operations has limited, and sometimes even blocked, the treatment options. The contribution of this paper is concept analysis and implementation of flexible virtual fixture for the novel hybrid parallel-serial mechanism and experimentally evaluation of this concept. The virtual fixture using this mechanism enables the user to adjust them even during the procedure. Pivoting around a Remote Center of Motion (RCM), which in retinal surgery is the incision point, is the most famous virtual fixture of ophthalmic surgery. Autonomous RCM adjustment for Vitreo-Retinal surgery, implying retinal reachability study, is the secondary contribution which is investigated in this paper.

Multi-robot collaborative platforms for humanitarian relief actions

In this paper we describe the main components and technical challenges required for the implementation of a multi-robot collaboration platform towards supporting humanitarian relief actions. The platform supports collaborative work between a fleet of UAVs, mobile stations and light-weight fast-speed robots. The platform can be used on both land or marine environments allowing a wide diversity of rescue, surveillance and relief operations. The paper presents the entire robotic system of the platform along with some mobile station-base collaborative tasks, inter UAVs and fast-speed mobile platform collaboration. Finally, we present potential application scenarios where these platforms can be deployed.

Uncalibrated stereo visual servoing for manipulators using virtual impedance control

In this paper, we present an uncalibrated position-based fixed-camera Visual Servoing for robot manipulators, where the goal is to track the 3D position and orientation of the target. The stereo system with 2 USB cameras is uncalibrated with respect to the robot base frame and the transformation between them is estimated on-line while performing the task. Dynamic impedance control is designed to generate a dynamic trajectory for the robot manipulator considering the dynamic environment constraints, such as: robot singularities avoidance and (self-/obstacle-) collision avoidance. Experiments have been carried out to verify performance of the proposed system on a real industrial robot, where the calibration estimation process and handling of all uncertainties in the environment are demonstrated. Moreover the uncalibrated stereo camera system can be manually moved while performing the task in order to obtain a clearer view and the re-calibration is performed automatically and on-line.