Tutorial - Robotics in the small Part II: Nanorobotics

Nanorobotics is the study of robotics at the nanometer scale, and includes robots that are nanoscale in size, i.e., nanorobots (which have yet to be realized), and large robots capable of manipulating objects that have dimensions in the nanoscale range with nanometer resolution, i.e., nanorobotic manipulators. Knowledge from mesoscopic physics, mesoscopic/supramolecular chemistry, and molecular biology at the nanometer scale converges to form the field. Various disciplines contribute to nanorobotics, including nanomaterial synthesis, nanobiotechnology, and microscopy for imaging and characterization. Such topics as self-assembly, nanorobotic assembly, and hybrid nanomanufacturing approaches for assembling nano building blocks into structures, tools, sensors, and actuators are considered areas of nanorobotic study. A current focus of nanorobotics is on the fabrication of nanoelectromechanical systems (NEMS), which may serve as components for future nanorobots. The main goals of nanorobotics are to provide effective tools for the experimental exploration of the nanoworld, and to push the boundaries of this exploration from a robotics research perspective.     

Playing it safe [human-friendly robots]

We have presented a new actuation concept for human-friendly robot design, referred to as DM/sup 2/. The new concept of DM/sup 2/ was demonstrated on a two-degree-of-freedom prototype robot arm that we designed and built to validate our approach. The new actuation approach substantially reduces the impact loads associated with uncontrolled manipulator collision by relocating the major source of actuation effort from the joint to the base of the manipulator. The emerging field of human-centered robotics focuses on application such as medical robotics and service robotics, which require close interaction between robotic manipulation systems and human beings, including direct human-manipulator contact. As a result, this system must consider the requirements of safety. To achieve safety we must employ multiple strategies involving all aspects of manipulator design.     

Nonlinear controller design for a magnetic levitation device

Various applications of micro-robotic technology suggest the use of new actuator systems which allow motions to be realized with micrometer accuracy. Conventional actuation techniques such as hydraulic or pneumatic systems are no longer capable of fulfilling the demands of hi-tech micro-scale areas such as miniaturized biomedical devices and MEMS production equipment. These applications pose significantly different problems from actuation on a large scale. In particular, large scale manipulation systems typically deal with sizable friction, whereas micro manipulation systems must minimize friction to achieve submicron precision and avoid generation of static electric fields. Recently, the magnetic levitation technique has been shown to be a feasible actuation method for micro-scale applications. In this paper, a magnetic levitation device is recalled from the authors’ previous work and a control approach is presented to achieve precise motion control of a magnetically levitated object with sub-micron positioning accuracy. The stability of the controller is discussed through the Lyapunov method. Experiments are conducted and showed that the proposed control technique is capable of performing a positioning operation with rms accuracy of 16 μm over a travel range of 30 mm. The nonlinear control strategy proposed in this paper showed a significant improvement in comparison with the conventional control strategies for large gap magnetic levitation systems.     

Design and performance of a micro-sized biomorphic compound eyewith a scanning retina

Proposes a design of a biomorphic micro visual sensor equipped with a mechanical scanning system. The sensor is inspired by the structure of the fly's compound eye, which was found to possess a unique muscle and tendon actuation system for its scanning retina. The improvement in micro-opto-electro-mechanical systems encourages the design of reliable, efficient, and integrated smart visual sensors for robotic applications, in particular, for the autonomous visually guided navigation of mobile robots. The authors have verified the effect of retinal scanning for a robotic visual system through the construction of a large-scale prototype at the millimeter scale. The performance of a newly fabricated microelectromechanical system prototype whose size approaches the order of the insects' compound eyes is then evaluated in comparison with that of the large-scale prototype. The micro-sized visual sensor is composed of a scanning microlens array (120 μm in lens diameter) and a photo-diode array. The actuation of the microlens array induces a rotation of the visual axes. According to the principle of retinal scanning, the micro-sensor is able to retrieve the local angular velocity with enhanced reliability     

Current research in multirobot systems

As research progresses in distributed robotic systems, more and more aspects of multirobot systems are being explored. This article describes advances in multirobot systems, and surveys the current state of the art. The focus is principally on research that has been demonstrated in physical robot implementations. I have identified eight primary research topics within multirobot systems—biological inspirations, communication, architectures, localization/mapping/exploration, object transport and manipulation, motion coordination, reconfigurable robots, and learning—and discuss the current state of research in these areas. As I describe each research area, I identify some key open issues in multirobot team research, and conclude by identifying several additional open research issues in distributed mobile robotic systems. This work was presented, in part, at the Seventh International Symposium on Artificial Life and Robotics, Oita, Japan, January 16–18, 2002     

Search and pursuit-evasion in mobile robotics

This paper surveys recent results in pursuit-evasion and autonomous search relevant to applications in mobile robotics. We provide a taxonomy of search problems that highlights the differences resulting from varying assumptions on the searchers, targets, and the environment. We then list a number of fundamental results in the areas of pursuit-evasion and probabilistic search, and we discuss field implementations on mobile robotic systems. In addition, we highlight current open problems in the area and explore avenues for future work.     

Immuno-inspired robotic applications: A review

The ability of artificial immune systems to adapt to varying pathogens makes such systems a suitable choice for various robotic applications. Generally, immunity-based robotic applications map local instantaneous sensory information into either an antigen or a co-stimulatory signal, according to the choice of representation schema. Algorithms then use relevant immune functions to output either evolved antibodies or maturity of dendritic cells, in terms of actuation signals. It is observed that researchers do not try to replicate the biological immunity but select necessary immune functions instead, resulting in an ad-hoc manner these applications are reported. On the other hand, the paradigm shift in robotics research from reactive to probabilistic approaches is also not being reflected in these applications. Authors, therefore, present a detailed review of immuno-inspired robotic applications in an attempt to identify the possible areas to explore. Moreover, the literature has been categorized according to the underlying immuno-definitions. Implementation details have been critically reviewed in terms of corresponding mathematical expressions and their representation schema that include binary, real or hybrid approaches. Limitations of reported applications have also been identified in light of modern immunological interpretations including the danger theory. As a result of this study, authors suggest a renewed focus on innate immunity, action contextualization prior to B/T cell invocation and behavior evolution instead of arbitration. In this context, a multi-tier immunological framework for robotics research, combining innate and adaptive components together is also suggested and skeletonized.     

Dynamically stable motion planning of wheeled robots for heavy object manipulation

Heavy object manipulation by wheeled mobile manipulators (WMM) may lead to serious consequences such as postural instability, and this necessitates dynamically stable planning based on systematic analysis to better predict and eliminate the possibility of toppling down. Although the problem of stable planning has been extensively examined in the context of humanoid robotics, fewer research has been devoted to that in the field of WMMs. In the present study, this challenging issue is investigated for WMMs during heavy object manipulation tasks. It is assumed that the initial and final poses of a heavy payload are specified. Based on these known postures of the payload, two proper configurations for robotic system are defined. Then, between these two initial and final poses, appropriate trajectories for multiple robotic arms relative to the moving base are planned without considering the postural stability of the system. Next, motion of the moving base is planned so that the stability of the overall system is guaranteed while its predetermined initial and final positions and velocities are fulfilled. To this end, the problem of stable planning is solved as an optimization problem. The obtained results reveal the merits of the proposed approach.     

Design and manufacturing of mobile micro manipulation system with a compliant piezoelectric actuator based micro gripper

This paper presents a new design of mobile micro manipulation system for robotic micro assembly where a compliant piezoelectric actuator based micro gripper is designed for handling the miniature parts and compensation of misalignment during peg-in-hole assembly is done because piezoelectric actuator has capability of producing the displacement in micron range and generates high force instantaneously. This adjusts the misalignment of peg during robotic micro assembly. The throughput/speed of mobile micro manipulation system is found for picking and placing the peg from one hole to next hole position. An analysis of piezoelectric actuator based micro gripper has been carried out where voltage is controlled through a proportional-derivative (PD) controller. By developing a prototype, it is demonstrated that compliant piezoelectric actuator based micro gripper is capable of handling the peg-in-hole assembly task in a mobile micro manipulation system.     

A Panoramic Survey on Grasping Research Trends and Topics

Abstract

Grasping and object manipulation is a key element of intelligent behavior. Many innovative cyberphysical systems involve some kind of object grasp and manipulation, to the extent that grasping has been recognized as a critical technology for the next generation industrial systems. In this survey, we aim to draw a broad landscape of applications and current research trends and topics relating to grasping techniques and tools. Applications range from biomedical and surgical to industrial warehouse pick and place tasks, covering a wide range of spatial scales, from micro to macro scales. The resources involved and research lines under development include the latest computational intelligence tools as well as the research on new materials and devices for sensing and actuation.     

Search and tracking algorithms for swarms of robots: A survey

Target search and tracking is a classical but difficult problem in many research domains, including computer vision, wireless sensor networks and robotics. We review the seminal works that addressed this problem in the area of swarm robotics, which is the application of swarm intelligence principles to the control of multi-robot systems. Robustness, scalability and flexibility, as well as distributed sensing, make swarm robotic systems well suited for the problem of target search and tracking in real-world applications. We classify the works we review according to the variations and aspects of the search and tracking problems they addressed. As this is a particularly application-driven research area, the adopted taxonomy makes this review serve as a quick reference guide to our readers in identifying related works and approaches according to their problem at hand. By no means is this an exhaustive review, but an overview for researchers who are new to the swarm robotics field, to help them easily start off their research.     

Mobile manipulation: The robotic assistant

Mobile manipulation capabilities are key to many new applications of robotics in space, underwater, construction, and service environments. This paper discusses the development of robotic “assistance” capabilities to aid workers in the accomplishment of a variety of physical operations and presents various control strategies developed for vehicle-arm coordination, compliant motion tasks, and cooperative manipulation between multiple platforms. These strategies have been implemented on two holonomic mobile platforms designed and built at Stanford in collaboration with Oak Ridge National Laboratories and Nomadic Technologies.     

Distributing a robotic system on a network: the ETHNOS approach

Cognitive activity in intelligent robotic systems has often been modeled as a set of communicating intelligent distributed agents or modules. Some examples in this field are blackboard architectures, hybrid models or subsumption architectures. The rapid progress of communication technology offers the possibility of distributing computation not only on different processes but on a network of computers. This both results in greater available computational power and it allows the robot to merge with the environment it operates in. In suitable intelligent buildings a mobile robot may open doors, turn on/off lights or even avoid obstacles based not only on its sensors and actuators but on the interaction with other robotic entities. In addition the range of robot interactions is now only limited by the network and thus the robot can operate remotely on the environment. Similarly, users can issue commands to remote robots and receive feedback in real-time. In this paper we propose a global approach to distributing a robotic system over a computer network. The approach is named ETHNOS (Expert Tribe in a Hybrid Network Operating System) because it is based on a novel operating system we developed specifically for distributed intelligent robotics. The paper focuses on its characteristics that make it well suited for network robotics applications. It also illustrates an example of a real application in the field of mobile robotics.     

Design, fabrication and control of a magnetic capsule-robot for the human esophagus

Much research on the development of a robotic capsule and micro robot for the diagnosis of gastrointestinal diseases has been carried out. The powering of these micro systems is becoming very challenging as the implementation of such systems is limited due to the existence of on-board power supplies. This paper presents a micro robotic system based on magnetic principles. The goal is to build a system in which a capsule-robot can be manipulated wirelessly inside an enclosed environment such as human??s body. A prototype of capsule-robot is built and tested, that can be remotely operated with three DOF in an enclosed environment by transferring magnetic energy and electromagnetic waves. A magnetic drive unit generates magnetic energy for the manipulation. Experimental results show the capsule-robot is manipulated and moved through a desired trajectory in a viscous fluid. The capsule-robot can be potentially used for endoscopy and colonoscopy.     

Meteorosensitive architecture: Biomimetic building skins based on materially embedded and hygroscopically enabled responsiveness

In this paper, the authors present research into autonomously responsive architectural systems that adapt to environmental changes using hygroscopic material properties. Instead of using superimposed layers of singular purpose mechanisms–for sensing, actuation, control and power–in the form of high-tech electronic equipment as is emblematic for current approaches to climate responsiveness in architecture, the presented research follows an integrative, no-tech strategy that can be considered to follow biological rather than mechanical principles. In nature plants employ different systems to respond to environmental changes. One particularly promising way is hygroscopic actuation, as it allows for metabolically independent movement and thus provides an interesting model for autonomous, passive and materially embedded responsiveness. The paper presents a comprehensive overview of the parameters, variables and syntactic elements that enable the development of such meteorosensitive architectural systems based on the biomimetic transfer of the hygroscopic actuation of plant cones. It provides a summary of five years of research by the authors on architectural systems which utilize the hygroscopic qualities of wooden veneer as a naturally produced constituent within weather responsive composite systems, which is presented through an extensive analysis of research samples, prototypes at various scales, and two comprehensive case studies of full scale constructions.