Chetan Kapoor

A reusable software architecture for manual controller integration

This paper examines the commonalities of manual controllers used in robotics for teleoperation. These include devices ranging from simple joysticks to force-reflecting controllers. The similarities in functionality and behaviour of these controllers is further exploited to develop a reusable software architecture for manual controller interfacing. The development of this architecture is based on object-oriented design. The application of this design philosophy led to the development of a hierarchy of software components that are manual controller independent and also have a standardized interface. Reusability of these components is supported through generality and extensibility. The key design requirements for this architecture were: open-system, reusable, application independent, extensive error-handling and safety checking, applicability to real-time control and simulation, and reduction in program development time. This paper discusses the software analysis and design issues that were faced to meet the architecture requirements. Further, this architecture is demonstrated using four different manual controllers and a teleoperated dual-arm robotic manipulator.

Trauma Pod: a semi‐automated telerobotic surgical system

The Trauma Pod (TP) vision is to develop a rapidly deployable robotic system to perform critical acute stabilization and/or surgical procedures, autonomously or in a teleoperative mode, on wounded soldiers in the battlefield who might otherwise die before treatment in a combat hospital could be provided.

A criteria-based approach to grasp synthesis

This study introduces a criteria-based methodology for grasp synthesis. The method allows the use of multiple performance criteria both at the finger and the hand levels, which are used to generate a preliminary grasp and an optimum grasp, respectively. The approach offers reduced complexity by decomposing grasp synthesis into manageable phases. A case study using a physical hand demonstrates the effectiveness of the method.

Collision avoidance techniques for tele-operated and autonomous manipulators in overlapping workspaces

This paper describes the integration of several techniques for cooperative control of both tele-operated and autonomous redundant manipulators with overlapping workspaces. Motivating this research is a tele-operated surgical manipulator(s) supported by autonomous robot(s) that insert/remove items from the surgical workspace. The dynamic and unpredictable location of obstacles in a small workspace requires a complete strategy to avoid collisions when completing critical tasks and minimizes the need for user (i.e. the surgeon) intervention to make path planning decisions or resolve impasse situations. Three techniques are integrated into the decision-making for the manipulators: an intelligent and intuitive EEF velocity scaling, coordinated null-space optimization across affected manipulators, and collision detection. Central to all three techniques is an estimated time- to-collision formulation that combines distances between objects with their higher order properties, thus only objects currently moving towards each other are included in the collision avoidance techniques. The use of multiple techniques derived from the terms of a single metric results in a computationally efficient strategy for tele-operated and autonomous manipulators sharing the same workspace.

Integrated teleoperation and automation for nuclear facility cleanup

Purpose – The objective of this work was to demonstrate a novel approach to human machine interaction that seamlessly uses teleoperation and automation in a complex environment.Design/methodology/approach – This work leverages developments in the area of operational software Operational Software Components for Advanced Robotics (OSCAR), decision making, human‐machine interface, and motion planning. This demonstration uses a 17 degrees‐of‐freedom (DOF) dual arm robot that is equipped with modern tool changers, crash protectors, force‐torque sensors and electrical and pneumatic power at the tools. Four different end‐effector tools are also provided. These are electric grippers, electric rotary saw, electric drill, and a pneumatic spray gun. The system can be used both in teleoperation and automation mode. In teleoperation mode, the user has a choice of five different input devices. These are computer keyboard, spaceball and spacemouse, RSI manual controller and kraft force feedback controller. Automation is...

Automatic code generation for actuator interfacing from a declarative specification

Common software design practices use object-oriented (OO) frameworks that structure software in terms of objects, classes, and packages; designers then create programs by inheritance and composition of classes and objects. Operational software components for advanced robotics (OSCAR) is one such framework for robot control software with abstractions for generalized kinematics, dynamics, performance criteria, decision making, and hardware interfacing. Even with OSCAR, writing new programs still requires a significant amount of manual labor. Feature-oriented programming (FOP) is method for software design that models and specifies programs in terms of features, where a feature encapsulates the common design decisions that occur in a domain. A set of features then forms a domain model for a product line architecture. Product variants in this product line can then be generated from a declarative specification. FOP and related technologies are emerging software engineering techniques for automatically generating programs. Our research applies FOP to robot controller software. As an example, the domain of hardware interfacing is analyzed and 41 features identified. A GUI for specifying and generating programs is presented as well. Analysis of features shows 200 possible different programs could be generated.

Generalized software components for reconfiguring hyper-redundant manipulators

An application of Operational Software Components for Advanced Robotics (OSCAR) - a generalized robotic software framework - for kinematic control of hyper-redundant, self-reconfigurable systems is presented. OSCAR includes generalized kinematics, dynamics, device interfacing, and criteria-based decision making. The developed application allows an operator to interactively reconfigure modular chains into parallel mechanisms, gait structures, and multiarm systems while maintaining full kinematic control of each chain. Examples using spatial systems with various geometries are presented with application pseudocode to illustrate high-level program development using OSCAR.

Extended generalized impedance control for redundant manipulators

An impedance control method for redundant manipulators called an extended generalized impedance control is developed. It is based on an extended task space formulation and generalized impedance control. With generalized impedance control, the manipulators end-effector position and force tracking abilities can be balanced by properly adjusting impedance parameters. Null space motion is controlled by tracking a minimal parameterization of null space velocity. Redundancy is then exploited by specifying a desired null space velocity trajectory that optimizes a performance index. The control algorithm is implemented as part of OSCAR (Operational Software Components for Advanced Robotics), keeping with the generality concept. Therefore, it can be easily deployed with any serial manipulator. The effectiveness of the proposed controller is illustrated by computer simulations of a complex 10-DOF spatial manipulator performing a cutting task.

A software architecture for multi-criteria decision making for advanced robotics

Presents a framework that facilitates the development of multi-criteria decision-making software for redundant manipulator control. This software architecture is based on object-oriented design and it meets the requirements of generality, extensibility, computational efficiency, and reduction in program development time. Analysis, design, and implementation were the three steps in the development of this architecture. Analysis involved the study of the multi-criteria decision-making domain. This included the information flow between different criteria and also their fusion. The design phase involved extracting the commonalties of various criteria and the specification of abstractions that could best model these criteria. The application of this philosophy led to the development of an architecture that is robot independent, scaleable, supports standardized interfaces, and is applicable to real-time control and simulation. This architecture is demonstrated using a sample application for controlling a 10 DOF manipulator.

Decision making for remote robotic operations

Robotic systems are often used for remote operations in Department of Energy Environmental Management applications because they allow the removal of personnel from dangerous environments. Typically, these systems are operated in pure teleoperation mode by a human operator. While these systems are capable of performing many tasks, their performance can be greatly enhanced through the use of telerobotics (a combination of teleoperation, automation, and decision making). This paper describes an analytical approach to decision making for robotic systems used in remote operations. This approach utilizes redundancy in the system or the task to improve the overall system performance based on analytical criteria. The approach is illustrated by application to the dual arm telerobot at Oak Ridge National Laboratory (ORNL) and the pit viper system at Pacific Northwest National Laboratory (PNNL). In both instances, decision making clearly reduces the operator involvement in tedious tasks while improving performance.