Robotics 2000

Deep Space 1 (DS1), launched on October 24, 1998, was the first mission of NASA's New Millennium program. DS1 was chartered to flight validate twelve high-risk, advanced technologies important for future space and Earth science programs. Advanced technologies tested during its primary mission included solar electric propulsion, high-power solar concentrator arrays, three on-board autonomy technologies, two low-mass science instrument packages, and several telecommunications and microelectronics devices. During the primary mission, which was completed in September 1999, the technology payload for the mission was exercised extensively to assess performance so subsequent missions will not have to incur the cost and risk of being the first users of these new capabilities. DS1 was the first deep space mission to use solar electric propulsion as its main source of propulsion. In addition, DS1 was the first mission to demonstrate the ability to perform autonomous on-board navigation for a deep space probe. Although DS1 was driven by the requirements of technology validation, it also presented an important opportunity to conduct solar system science, though as a secondary objective to its main technology validation mission goals. As such, the spacecraft flew by asteroid Braille in July of 1999; later encounters during its recently approved extended mission with comets Wilson-Harrington and Borrelly are planned in the year 2001. This paper will describe the technology and mission aspects of Deep Space 1.

Space based construction metrology has a great potential for monetary and effort savings through the creation and use of open industry standards to support construction automation in space. Current technology for construction automation in space requires either one vendor to provide an entire solution, or an organization, such as NASA, to coordinate the efforts of vendors in tightly integrated projects that lock vendors in for the life of a facility. Open space based construction metrology standards could provide a means to promote competition over the life of a facility by supporting interoperability. LiveView is being designed to meet the goal of construction metrology automation, and may be applicable to special issues arising in an orbital environment.

The present paper is devoted to generalization of the VNIITRANSMASH experience on projecting and testing space robotic systems (SRS). They are mobile and steerable systems as well as their physical models (demonstrators), intended for Earth-based refining. Technical data for some systems are given. Information concerning these systems was not reflected in proceedings of previous "Space" conferences.

In 2000 the European Robotic Arm (ERA) will be launched and attached to the Russian segment of International Space Station Alpha. The arm will initially be used to support assembly operations on the Russian segment, and will eventually be used as servicing tool for at least ten years during Space Station life cycle. The Mission Preparation and Training Equipment (MPTE) is an important part of the ERA project. ERA operations will be prepared, planned, and supported from the MPTE, and ERA operators will be trained with the MPTE. Three identical versions of the MPTE will be installed at RSC/Energia-MCC and at the Gagarin Cosmonaut Training Centre in Russia, and at ESA/ESTEC in the Netherlands. Each of the facilities has its particular function in support of ERA operations, training, and maintenance. The design of the MPTE is based on existing tools and facilities to a maximum extent. Re-use is made of the real-time operations simulation facility EUROSIM, including the Image Generation Subsystem (IGS), and of the Columbus Ground Software system (CGS). Also, re-use is made of developments from the ERA projects, both hardware and software. Next to elegant breadboard systems of ERA flight hardware, development support simulation models from the ERA Simulations Facility (ESF) are re-used.

The rendezvous docking and space robot technologies are indispensable for future space activities such as construction and operation of the international space station, inspection and repair of orbiting satellites, and conducting lunar/planetary explorations. The National Space Development Agency of Japan (NASDA) developed and launched an engineering test satellite named ETS-VII(Engineering Test Satellite #7) on November 28, 1997 to conduct the rendezvous docking and space robot technology experiments. ETS-VII carries a robot arm, which is teleoperated from the ground and is being used in various tasks such as exchange of equipment. It also conducted the automated rendezvous docking experiments. This paper summarizes the ETS-VII mission mainly its robot experiment results and its applications.

NASA has been commissioned to investigate the feasibility of an orbiting Space Solar Power (SSP)system that is capable of generating power from space and transmitting the power to earth based rectennas. The structures for these systems would be large (1 km and greater) and would require robotic assembly, maintenance and operations. The robotic and autonomous operations required for SSP can be divided into three main areas: 1) initial assembly of the transmitter array and the photovoltaic power subsystem, 2) initial inspection of the assembled structure to determine that the assembly process has been correctly conducted and continued inspection of the system to evaluate its integrity and functionality, and 3) maintenance and repair of transmitter elements or tiles and the photovoltaic power subsystem. Due to the wide spectrum of the required operations, no single robotic system will suffice. Variation in robot design will be dictated both by the type of work performed, as well as the system's location relative to the SSP platform. For example, a heavy OMV hauler may be necessary to move large components into position, while a small legged robot may be needed to crawl into tight spaces for inspection and maintenance. However, the total number of unique systems can be reduced through reconfigurability of those systems. In the case of the small inspection/maintenance robot, the ability to freely switch end-effector tools would be invaulable. This paper will discuss design options and the technology development needs for the Space Solar Power system, after a brief introduction to some of the basic system configurations.

A systematic and steady exploration of the outer space by the mankind brings up the requirements for a development of new kinds of modern machines. Robotics occupies a leading position among them. Remotely-controlled or completely automated robotic means are occupying more and more ponderable position in an exploration of the nearest space and planets. An analysis of the experience of cosmonauts' outer space activities during the operation period of the orbital stations "Salut-6", "Salut-7" and, especially, "Mir" showed that all main systems as inside pressure modules as outside them were subjected to technical maintenance and repair works. Moreover, the volume of repair and restoration works was increasing as far as equipment and systems were worn out. it achieved 50% of the total volume of cosmonauts' works. The long duration of operations is caused also by the extremely low productivity of cosmonauts working in space suits without bearing surface. One can suppose that similar time outlay dynamics will take place at the newly developed international space station "Alpha" also. Moreover, a part of operations fulfilled by the cosmonauts outside pressure modules will be increased to a great extent because of the increasing of amount and complexity of the on-board equipment installed on the external surface of the station and because of the experimental operations amount increasing.

Canada has invested over $1.4B during the past 25 years in the development of robotic manipulator systems for the Space Shuttle and Space Station Programs. Mars, Moon and other bodies in our solar system are seen as an excellent opportunity to utilize this established advanced space robotic capability as a base for continued robotics technology development and utilization. Coupled with a strong interest from the Canadian planetary science community, and the recent launch of a new Space Exploration Program by the Canadian Space Agency, this has lead to some exciting robotic development activities to utilize this capability to support Canadian participation in planetary missions. This paper gives an overview of these activities including identification of near-term international planetary missions expected to use Canadian robotic manipulators, design reference tasks for the robotic activities, new design methodologies, hardware prototyping activities, leapfrog technology thrusts, together with automation and reliability issues.

In this paper, the vibration of a space robotic arm with joint flexibility is discussed. Considering manipulability of the robotic arm, the berthing manipulation may cause flexible vibration due to joint elasticity. Since the natural frequency of the robotic arm changes according to its configuration changes, there is a possibility of resonance between the arm vibration and the flexible paddle vibration, and the disturbances caused by the arm vibration have influence on the satellite attitude. The authors evaluate the arm vibration during the berthing manipulations through both the data analyses of berthing experiments and the simulations.

Since several years DASA — Space Infrastructure develops key technology components and basic systems for space robots and future service robot applications. Since space "service robots" and terrestrial "service robots" show strong similarity of basic functional requirements, technologies and components developed are basically usable for both areas. The paper presents an overview of examples of recent developments an application examples. This covers demonstrator systems, control systems, 3D sensor systems, image processing, modular robot arms and prototype applications.

Recently the construction of the International Space Station (ISS) has begun and the Space Shuttle Remote Manipulator System (SRMS) and the Space Station Remote Manipulator System (SSRMS) are used for the construction. These manipulators are operated by onboard crews and accomplish the tasks that cannot be done by human hands, such as the transportation of the large and heavy objects. Although these manipulators are useful for these kinds of tasks, there are plenty of needs to use more advanced manipulator systems for in-orbit servicing applications such as unmanned orbital service robots and Extra Vehicular Activity (EVA) support robots. There are also a lot of challenging technologies to realize such applications effectively. Thus we have been doing research on technologies for the next generation in-orbit servicing robot systems. The Reconfigurable Space Manipulator (RSM) is the one of the results from our research. The manipulator is designed to apply for various space applications. This paper presents the task analysis results for the next generation in-orbit servicing robots, the system concept of the Reconfigurable Space Manipulator and some system design results for the manipulator.

Efforts are underway at the National Institute of Standards and Technology (NIST) to develop a web- based system for rapid tracking, identifying, and locating manufactured components on the construction jobsite. The approach involves the use of RFID and barcode identification systems, 3D long range coordinate measurement technologies, portable/wearable computers, wireless communications, high speed networking, temporal project databases, web-based data analysis, and 3D user interfaces to provide as-is and as-built component data at the actual construction site. These same techniques may prove useful for planning and execution of construction operations on other planets. Present research is focused on developing compact, rugged, wireless part status managers, interoperability protocols for data transmission, and 3D site visualizers which reflect the current state of tracked components on the construction site. Ultimately, these field measurements will be used to generate automated material acceptance and payment transactions, damaged component rejection notices, and production rate change requests to fabricators. This paper discusses the methods employed to achieve this capability in a prototype system.

The content of the paper is focused on the six degrees-of-freedom measurement (DOF) of structural dynamic properties in engineering constructions and for control operation in space. Described measurement system is derived from a pyramid modular sensory system for the sampling of six- component information about three axial shiftings and three angular displacements. The subject of this device is the sampling and information processing used in the conversion of four 2-D CCD arrays images into three axial and three angular displacement values. Every CCD array image consists of one light spot produced by light beam from four laser sources. These light beams form the edges of a pyramidal shape with four 2-D arrays forming its base and the origin of the laser sources is forming its apex. The modular design presented here enables easy customization of six DOF measurement by means of three universal portable modules.

Efforts are underway at the National Institute of Standards and Technology (NIST) to develop automated non-intrusive production measurement systems and procedures for monitoring the status of general earthmoving operations at typical construction sites. The approach involves the use of auto- registered Lidar range sensing systems, wireless communications, high speed networking, temporal project databases, web-based data analysis and 3D user interfaces to provide useful derivative quantities to the earthmoving contractor while at the actual construction site. These same techniques may prove useful for planning and execution of remote, autonomous excavation on other planets. Present research is focused on developing methods for automated registration of independent 2-1/2D range data, automated volumetric calculations, including cut/fill requirements and amounts of raw material removed or placed, and web-based 3D site simulators which reflect the instant terrain geometry. This paper discusses the methods employed to achieve this capability and plans currently underway for daily construction monitoring at a $6M process plant in the spring of 2000.

Construction has many of the most hazardous work environments of any industry in the world. Despite this fact, robotics has received very little attention and is widely considered as unsuitable and cost-prohibitive. Many of the few attempts that have been made have failed for various reasons, one of which is the lack of a cross-disciplinary approach by the developers. This paper presents an effort to develop an innovative alternative to the present method used for inspecting drilled shafts needed for the construction of bridge supports. It describes the first prototype system including the inspection/testing capsule, the deployment system, and some field tests that were conducted. The goal is to eliminate the need for a foundation inspector to be lowered 100 to 200 feet into a narrow unsupported shaft. Additionally, it will allow for inspection of slurry or water filled holes, which are impossible to accurately inspect without pumping them empty. The success of the project depends heavily on a close working relationship of researchers from several disciplines such as civil-, mechanical-, and electrical engineering.

Positioning and suspending materials over large space volumes is a fundamental process in the construction industry. Traditional equipment such as cranes cannot satisfy the accuracy requirement due to their structural limitation. Also, the large size and complexity of modern cranes require new capabilities, or intelligence, to interact with the environment automatically. Because of the unpredictable behavior of the environment on a construction site (for instance, wind), traditional control concepts and methods are insufficient. To ensure the necessary accuracy and safety of the larger and heavier construction machines, the increased use of sensors and embedded controls is unavoidable. This paper discusses the mechanics of a Crane-Mounted Inverted Stewart Platform (C-MISP) prototype as an approach to fulfill the above demands. The C-MISP is designed to have all degrees of freedom kinematically constrained by supporting cables, making it very stable during manipulation. Through integration of a spatial positioning system and various on-board sensors, the C-MISP can monitor the environmental changes as well as its own work condition in real time. Such sensing information can then be used by a control and decision making unit to decide if the C-MISP parameters should be changed in order to maintain its position and path accuracy. In addition to the structural mechanics, the initial results of a study to analyze the behavior of C-MISP under wind loads are also discussed in this paper.

The paper contains principals of creating of proposed by the authors a so-called universal platform — a relatively small, autonomous device, which is fixed directly to a load. It has to operate in complex with the helicopter and other lifting mechanisms (crane, balloon etc.), and provides in automatic mode a highly accurate installation of loads during construction and assembly work. The laboratory model ot the platform and requirements to its separate blocks are described. The paper contains also a detailed description of specially developed platform control algorithm and principles of device operating in complex with helicopter (as the most complicated version of assembly works). Results of computer simulation confirm the possibility of creating of described device. The paper contains a few proposals on the platform industrial application.

Excavation, and in particular trenching and pipe-laying, presents a hazardous working environment for humans. Many hazards exist including the possibility of collapsing trench walls, heavy objects accidentally being dropped into the opening, and buried utilities (e.g., power lines) being damaged during the operation. This paper will present a framework for the potential economic benefit assessment that can be used for a remote pipe laying technology. The analysis will include actual data from field observations and tests, It will also describe the newest version of teleoperated pipe manipulator (PipeMan).

Advances in embedded computer architecture, digital signal processing, guidance and navigation, and digital sensing have made it possible to develop relatively compact instruments that can be used to create highly accurate three dimensional maps of channelized aquifers (flooded spring tunnels), bypass tunnels for dams, storm runoff networks, freshwater delivery tunnels, and other submarine features. One such implementation was recently designed and built for a National Geographic Society expedition to Wakulla Springs, Florida and was used to create the first three dimensional cave map. The Wakulla Digital Wall Mapper (DWM) consisted of a series of bulkhead-isolated cylinders measuring 324 mm diameter by 1122 mm in length and weighing 82 kg. The DWM contained five integrated subsystems including an onboard guidance and navigation system, a custom-designed sonar array, a digital user interface, a pitch/yaw control system, and a master integration and data management system. In all, eight onboard computers control the instrument. Drift in the Inertial Measurement Unit (IMU) was the major design concern since it directly affected the accuracy of the maps generated. A high-accuracy reference network of induction radio beacons was used to provide the necessary control. It was found that a time-based drift compensation algorithm, working between radio control points, provided a useful and simple approach to positional error reduction.

The main goals of this research were to 1) refine manufacturing processes in order to develop novel soft, highly compliant and efficient electroactive materials for 2) subsequent characterization and integration into a prototype autonomous aquatic vehicle as a visible demonstration platform. Therefore several manufacturing processes to develop active polymeric composites were investigated and refined to create robust and efficient artificial muscle fin actuators. In this effort, several polymer materials, geometric shapes and thickness of the fin were investigated. An experimental static bench-test setup was then instrumented to characterize forward thrust force and evaluate efficient input driving signals to the actuator fin. All characterization data were obtained using a laptop PC-platform LabVIEW data acquisition system. A radio-controlled vehicle utilizing the optimized fin propulsors and all the onboard hardware to generate power and control signals was then designed and tested for optimum forward cruising speed and simple steering maneuver. The results showed that the proposed electroactive fin could be a viable candidate for application in low powered autonomous aquatic swimming vehicles.

The remotely operated vehicle (ROV) was initially developed for inspection purposes and for monitoring of diver activities on offshore petroleum rigs. The ROV gradually replaced divers in many inspection scenarios and evolved primarily as an exploratory or inspection device that allowed access to environments considered too dangerous or expensive for manned intervention. Research in ocean sciences and particularly in military technology helped to drive ROV capabilities beyond mere visual observation to include tooling packages for light work such as scientific sampling and performance of specific tasks such as mine detection and disablement. More advanced sensor capabilities (such as sonar) were gradually incorporated, primarily for navigation. Concurrently, the petroleum industry steadily pushed the capabilities of work machines to new levels of performance. Today, some industrial centres such as Norway, have a `no man in the water' policy intended to maximise reliance on ROVs to promote diver safety and reduce direct and indirect (insurance) costs associated with dive operations. Many subsea installations are now designed exclusively for ROV maintenance using dedicated tooling packages. Pipe and telecommunications lines are routinely laid over thousands of kilometres using specialized trench-and-fill ROVs equipped with high power water jets for excavation and burial.

In this paper a novel haptic interface is presented to enable human-operators to "feel" and intuitively mirror the stiffness/forces at remote/virtual sites enabling control of robots as human-surrogates. The proposed haptic interface is intended to provide human operators intuitive feeling of the stiffness and forces at remote or virtual sites in support of space robots performing dexterous manipulation tasks (such as operating a wrench or a drill). Remote applications are referred to the control of actual robots whereas virtual applications are referred to simulated operations. The developed haptic interface will be applicable to IVA operated robotic EVA tasks to enhance human performance, extend crew capability and assure crew safety. The novel device that is presented here employs Electro-rheological Fluids (ERF), which are electroactive polymers that change their viscosity when electrically stimulated.

The authors have designed and analyzed a lightweight flexible nonplanar manipulator testbed. The results of this study emphasize actual manipulator CAD/CAM design, analysis and hardware selection. The manipulator design has kinematics similar to a standard industrial robot, such as a PUMA 560, except that the linkages are all in-line without offsets. Counterbalances are used to offset the effects of gravity and reduce static loading. Direct-drive motors are used to provide gross motion which emphasizes link dynamics over actuator dynamics. To compensate for the link dynamics active graphite/epoxy composite links have been designed and constructed. The active composite links include embedded strain sensors and actuators to facilitate active vibration suppression during trajectory maneuvers.

For many years, electroactive polymers (EAP) received relatively little attention due to the small number of available materials and their limited actuation capability. The recent emergence of EAP materials with large displacement response changed the paradigm of these materials and their potential capability. The main attractive characteristic of EAP is their operational similarity to biological muscles, particularly their resilience and ability to induce large actuation strains. Unique robotic components and miniature devices are being explored, where EAP serve as actuators to enable new capabilities. In recognition of the need for international cooperation among the developers, users and potential sponsors, an SPIE Conference was organized for the first time on March 1–2, 1999, in Newport Beach, California. The conference was the largest ever on EAP, and it marked an important milestone, turning the spotlight onto these emerging materials and their potential. Following this success, an MRS conference was initiated to address the fundamental issues related to the material science of EAP. The WW-EAP newsletter was initiated to bring the worldwide EAP community even closer. A homepage was also created to link worldwide EAP research and development facilities websites. In this paper, the current capabilities and potentials as well as the challenges of state-of-the art EAP will be reviewed.

By current projections, the requirement for extravehicular operations will increase exponentially in the eras of International Space Station and planned human exploration of Mars. The best hope in meeting this rapidly growing need is in exploiting the complementary capabilities of humans and dexterous robots for performing advanced space operations, including space station maintenance, lunar or Mars base construction, and extended planetary surface exploration. This paper details a number of approaches to human/robotic cooperation, based on past, current, and near-term simulations. Results to date clearly indicate that human/robot teams, working closely together, provide significantly greater productivity than either component working alone.

Typically, roboticists invoice the animal world conceptually as a source of inspiration for finding new approaches to efficient locomotion, perception and intelligent control [Brooks 91], [Hallam, Walker 93], [Aloimonos 97]. The first part of this paper summarizes previous work on designing a robot to share a space with a simple animal. A series of experiments between a mobile robot and three chickens in a cage are described. Techniques are described to mechanically reduce chickens' anxiety towards moving machinery. The second part of this paper places these insights into the wider context of robot design.

This paper presents some work performed to date which is intended to lead to the development of a remotely operated system which would enable visual monitoring of surgical procedures at distant locations. This concept has been developed in the laboratory but not yet demonstrated under field condtions. Using existing technologies in a new configuration the system would assist in performing complex surgical procedures at remote locations where specialist surgeons are normally unavailable. With this system, a remotely based, general surgeon performing an operation can consult and interact with specialist surgeons through visual observation and voice communications. The prototype system consists of a six degree-of-freedom robot with an independently steerable CCD colour camera mounted on the end-effector. The operation of the device, by means of a joystick, comprises the movement of the robot to a suitable location for viewing the surgery. Visual and audio feedback to the expert surgeon, as well as the camera control, would be via a LAN or ISDN connection and by the implementation of a commercial video-conferencing package while the control signals for the robot arm are transmitted via a separate modem telephone line.

As known, gravity on other planets, their satellites, small planets essentially defers from Earth gravity. Reliability of spacecrafts is largely provided by their on-ground tests during which various space factors, in particular, low gravity or weightlessness are simulated. To simulate gravity of other planets while performing on-ground tests of planetary rovers and other space systems of various applications (satellittes, multisectional, mechanisms) mechanical systems have been developed (unloading devices — UD). Simulators are presented in progress. Various design of simulators as well as their technical characteristics have been considered. Promising concept for simulators creation based on a simulator family developed (more than 50 types) is of specialists interest.

One of the important problems of the piloted space exploration is a provision of safety and vital activity for crews. Among the specific tasks being solved at the State Scientific Center CRDI of Robotics and Technical Cybernetics in the frame if this problem are the following: 1) measurement of navigation parameters at the most crucial phases of space flying vehicles flights (during descending, soft landing, docking); 2) leakage check of manned space crafts and orbital stations; and 3) power supply systems control and monitoring. To solve each of the above mentioned tasks the investigations are carried out with the purpose of substantiated choosing of the principles being optimal for an application in specific measuring systems.

The purpose of this work is to plan and control task oriented configuration changes in a metamorphic robotic system, formed by a colony of axisymmetric holons moving to inspect pipe inner surfaces. The metamorphic robotic system in question, is a reconfigurable robotic structure made up of identical, independently controlled, mechatronic modules (holons) constituting a colony. The holons in that colony have very limited individual task abilities and are only capable of connecting, disconnecting and rotating about their center of symmetry while climbing over other holons. But it is only when they come together to form a colony that they can be used as a robotic system to perform many tasks, such as pipe surface inspection. The metamorphic inspection system has the advantages of robust reconfigurability, that can only be achieved by an efficient adaptable control mechanism which results from the difficult motion-planning problem for the colony. In this work, we consider three well-known motion-planning strategies that make use of different heuristics: "The Short Path Algorithm, The Artificial Potential Algorithm and The Sub-Goals Algorithm", and in order to generate an adaptable motion-planning and control strategy in possibly changing environments and achieve the best result in any environment, our work proposes to use all three strategies together, combined with the principles of the "mixed strategy" of Game Theory. The general path-planning strategy that we develop in this paper, switches from one of the three strategies to another, so that, at every step, the most suitable strategy is used and a result better than or equal to the "best" of the three strategies is achieved in all cases.

Robots used for tasks in hazardous environments frequency must cope with environmental uncertainty. The objects which must be manipulated are not well known in advance. Multifingered dexterous grippers are useful for grasping objects in uncertain environments. A fully enveloping grasp, also called a power grasp, is well suited for stable grasping in such unstructured environments. This paper describes the development of an adaptive power grasp planner. The system is based on a neural network which is trained on a variety of primitive shapes. When presented with a new object, the planner can generalize to achieve a secure grasp. Essential to the training of the neural network is the concept of grasp quality, which is determined from the convex hull of applied unit forces in wrench space. The mathematical framework and examples of grasp quality are presented, along with a description of the dexterous hand used for experimentation.

This paper presents an image-based, real-time, visual servoing system capable of tracking unknown 3-D motion with high precision. The hardware system we used to achieve this purpose is The Real-time Intelligently ControLled Optical Positioning System (TRICLOPS). TRICLOPS mimics the foveal-peripheral capability of the human visual system by combining the visual sensing of a center camera with a wide angle lens (low resolution) with that of two vergence cameras with telephoto lenses (high resolution). The goal of tracking is to keep the object of interest in the optical axis of all three cameras. The rotation velocity input for the central camera system is obtained by the conventional image Jacobian method. The relative rotational positions of the two vergence cameras are obtained by taking the atan of the object position offset from the origin in the image plane over the focal length. Sub-pixel resolution can be obtained when the center camera and the two vergence cameras are combined in this fashion, especially when the object is close to the origin of the world frame.

This paper aims to remove the major limitation of contemporary machines which is the inherent lack of sensory capabilities and give machines the ability to sense its environment by vision. Vision is a useful sensor since it mimics the human sense of vision and helps in non-contact measurement. A machine such as a robot whose duties include navigation may be called upon to perform in many different environments. In such fluid environments it would be unlikely that a geometric model will always be available , and arranging and testing fiducial markers may be onerous and impossible. Here we propose a framework that exploit continuity of image sequences. The image based techniques allow accurate motion without a precise geometric model of the environment and give added speed and robustness due to the predictive information available. The machine is trained in the environment in which it is supposed to function andduring that period it collects the information of it's work-space as a sequence of images. The image sequences are then used to form a map-like directed graph. When put into operation the machine is able to identify its surroundings by a comparison done with the current image it is viewing and the image stored during the training phase. By identifying the change in position, orientation and size of the markers (which are any visual entity that is in some way distinctive and meaningful) in the object, the machine is able to make sense of its domain and able to respond appropriately. This algorithm when enhanced with more powerful image comparison algorithms such as Wavelet Based Image Indexing is very fast, reliable and efficient and also has the added advantage of lesser amounts of memory for storing the image sequences. This algorithm also has the capability to adjust with changing environments by modifying the existing map whenever a change occurs around its environment. Thus our algorithm has very wide use in fields of under-sea navigation, security robots, robot delivery systems etc.

In this paper, the model predictive control (MPC) technique is applied to control a multi-degree-of-freedom industrial robot. Different from the conventional MPC, the predictive model used in this paper is non-linear. In this paper, the properties of the MPC method using a non-linear predictive model to control an industrial robot are studied.

Navigation and control of autonomous systems are currently being investigated for MARS greenhouse applications where these autonomous systems should be capable of navigating in the MARS greenhouse, perform tasks such as farming, harvesting, and so on. Demonstration of such an autonomous system is contingent upon developing novel coordinated control methodologies. A neural network (NN) controller is introduced for the coordinated motion of the base and the arm using adaptive feedback linearization. Using this adaptive NN controller the uniform ultimate boundedness of the closed-loop signals is presented and that the controller achieves tracking. The issue of maintaining a desired course and speed as the onboard arm moves to its desired position is considered. Simulation results are presented in order to justify the theoretical conclusions.

A principal scheme of calculations of control algorithm with `model' is described in the paper. As an object of control an automatic Space based module (platform), capable to execute different dynamic operations in Space is overviewed. The control system uses the position-sensitive optical system for obtaining the initial data about an object spatial position and pulse jet engines as an executive device. It is shown that a proposed method allows to calculate the exact current values of spatial coordinates, velocities and forces acting at the object during the flight. This in turn allows to realize an original scheme of `permanent' solution of the terminal task and to receive the current values of power pulses. Finally, on the base of results of calculation the control system constructs a so-called `flexible' trajectory of flight, providing an accurate and stable toward the random interference's execution of the dynamic process.

The objective of this work is to describe the design and the implementation of an experiment to study the dynamics, the experimental identification and the active vibration control of a Flexible Structure Mounted Manipulator System (FSMS). The system consists of a three degree of freedom cylindrical manipulator system with a flexible link on its tip. A two-degree of freedom micro-manipulator is mounted on the flexible link of the macro manipulator. The dynamic modeling and experimental modal analysis identification in the frequency domain are being applied to design active digital control strategies for the micro-manipulator system to damp the mechanical vibrations of the flexible structure on the tip of the macro-manipulator system.

Over the past several years, there has been a rapidly expanding interest in the study and construction of a new class of robot manipulators which utilize high degree of freedom, or continuous, backbone structures. In this paper, we consider some basic properties of these "continuum" or "hyper-redundant" robots. We base our analysis around remotely-driven, tendon-actuated manipulators such as the Rice/Clemson "Elephant's Trunk". We briefly discuss the kinematic model, before detailing how to approach the inverse kinematics for a planar continuum robot by decomposition into either a natural or a wavelet basis. We also examine how a wavelet decomposition method can help resolve redundancy in a planar continuum robot.

The harsh nature of planetary surfaces introduces many new constraints into the types of control systems suitable for use in such environments. These include low power requirements, operation within wide temperature extremes, relatively low computing capabilities and onboard memory, and multiple terrain types ranging from featureless flat plains to sheer cliffs. This paper presents the results of ongoing work at JPL and USC in autonomous rover control, which has concentrated on the development of a behavior-based control system called BISMARC. BISMARC includes full sensor and mobility models, geometric constraints, and environmental feedback based on the SRR/FIDO rovers at JPL. It is based on a biologically motivated navigation system derived from a study of human path planning in complicated exterior environments. The system has had over 800 simulation runs of a multiple cooperating rover, multiple sample return mission scenario with an overall success rate of 98.9%, and is currently being tested on the SRR rover in the Planetary Robotics Lab at JPL.

The natural trackability concept is extended to redundant robots controlled in Cartesian space. The necessary condition for finite-time natural trackability is presented for multi degree-of-freedom robots with unknown internal dynamics. A PID high-gain natural tracking control is synthesized to force a naturally trackable robot system to exhibit a prespecified elementwise exponential tracking. The tracking error is exponentially reduced from some unknown non-zero initial condition to zero in finite-time while the robot is subjected to internal non-linear, unknown, unmeasured, disturbances. The control is synthesized using the Cartesian tracking error, the pseudo-inverse of a product of the output Jacobian matrix, inertia matrix, and the control matrix, and the positive sum of the just realized control. A simulation is shown for a redundant multi degree-of-freedom robot that demonstrates elementwise exponential natural tracking control in Cartesian space.

Making the driver output impedance active allows reducing the sensitivity of the motor angular velocity to variations of the load parameters. Compensating the voltage drop on the motor winding, and making the output impedance of the driver the negative of the impedance of the motor winding are the two potentially equivalent design methods considered in this paper. Performances of the systems using a current driver, a voltage driver, and a driver with active output impedance are compared in applications to spacecraft antenna pointing and to a planetary rover wheel control.

The paper describes the second stage in the development of the floor-tiling robot — SHAMIR. Both the development and the performance measurements of the robot were carried out with a graphic simulation system. It was decided to concentrate, at this stage of the development, on the robot's autonomy at a workstation, which means that all operations at a workstation — stabilizing and calibrating, loading tiles, etc. — including real-time quality assurance (QA) are done without human intervention, while the transfer between workstations is assisted by an operator. The QA function is needed in order to allow accurate placing of the tiles in straight lines and with a uniform distance between them. Additionally, the QA function has to identify defective tiles. A computer vision system was developed to perform the QA functions. The prototype, its operational principles, and the experiments are described.

The Inflatable Rover uses novel, large, inflatable wheels to climb over rocks, instead of traveling around them, thus enabling it to traverse over 99% of the Martian surface. Preliminary tests using commercial nylon balloons as tires, a rigid metal chassis, and a simple, joy-stick control, have shown great promise. Tests have been successfully conducted in rugged rocky canyons, on giant sand dunes, and on calm lakes (simulating the liquid methane lakes anticipated on Saturn's moon Titan). Future work will be concentrated in the areas of materials research for the inflatable tires, development of a collapsible chassis, and adaptation of existing algorithms for image recognition and hazard avoidance.

Autonomous mobile robots have become a key technology for unmanned planetary missions. To cope with the rough terrain encountered on most of the planets of interest, new locomotion concepts for rovers and micro-rovers have to be developed and investigated. The most advanced locomotion concepts are based on wheels or caterpillars (e.g. Sojourner (NASA) or Nanokhod (ESA)). These rovers have clear advantages regarding power efficiency and complexity if compared with walking robots. However, they still have quite limited climbing abilities. Typically they can only overcome obstacle of their wheel size. In our paper we present an innovative rover concept with 6 motorized wheels. Using a rhombus configuration, the rover has a steering wheel in the front and the rear, and two wheels arranged on a bogie on each side. The front wheel has a spring suspension to guarantee optimal ground contact of all wheels at any time. The steering of the rover is realized by synchronizing the steering of the front and rear wheel and the speed difference of the bogie wheels. This allows for high precision maneuvers and even turning on the spot with minimum slip. The use of parallel articulations for the front wheel and the bogies enables to set a virtual center of rotation at the level of the wheel axis. This insuresmaximum stability and climbing abilities even for very low friction coefficients between the wheel and the ground. A well functioning prototype has been designed and manufactured in our lab. It shows excellent performance surpassing our expectations. This rover is able to passively overcome unstructured obstacles of up to two times its wheel diameter and can climb stairs with steps of over 20 cm.

Infrastructure support for robotic colonies, Mars habitat for humans, and/or robotic exploration of planetary surfaces will need to rely on the field deployment of multiple robust robots. This support includes such tasks as the deployment and servicing of power systems and in-situ resource utilization (ISRU) generators, establishing long-life robotic science stations for measurement and communications, construction of beaconed roadways, and the site preparation and deployment of human habitat modules. Precursor robotic missions to Mars that involve teams of multiple cooperating robots to accomplish some of these tasks is a cost effective solution to the possible long timeline necessary for the deployment of a human habitat. Ongoing work at JPL in the area or robot colonies is investigating many of the technology developments necessary for such an ambitious undertaking. Some of the issues that are being addressed include behavior-based control systems for multiple cooperating robots, development of autonomous robotic systems for the repair of disabled robots, and the design and development of robotic platforms for construction tasks such as material transport and surface clearing. This paper presents the results of an examination of requirements for robotic precursor missions to Mars.

The exciting possibility of water, raw materials, and even life on other planets and satellites in our solar system will require the development of mechanisms for low-cost, fault-tolerant exploration of these bodies. One approach to the development of these mechanisms is the use of a large number of small, inexpensive robots acting cooperatively as a swarm of insects might in foraging for food. This paper examines some of the issues involved in using "swarms" of small, inexpensive, insect-like robots for planetary exploration. Specifically, this paper discusses ongoing work with robots like Jonathan Mills' Stiquito or Lego platforms used to investigate swarm behaviors for the purpose of planetary exploration. This paper addresses investigations into methods of locomotion, comparing the advantages of legs, wheels, and tracks for robots operating in a variety of hostile environments. Next, the advantages and disadvantages of two types of swarm control are discussed: centralized control using a "queen" to control the swarm and decentralized control using identical, completely autonomous robots acting in concert. Some possible methods of collecting data and returning it to investigators on Earth are also discussed. Simulation results for the various control strategies are presented, as are experimental results, where they have been completed. Since this is ongoing research, this paper concludes with a discussion of topics requiring further research.

The objective of the Basic UXO Gathering System (BUGS) is to develop, test, evaluate, and demonstrate the use of multiple small robots in neutralizing unexploded ordnance in contaminated land areas. We are studying control methodologies and working on multiple autonomous robots to perform a practical and useful UXO (Unexploded Ordnance) clearance mission. It is important to select a multiple-robotic system approach that is reliable, economical, and robust enough to operate in an unknown environment. This paper addresses the completed milestones at NAVEODTECHDIV, in building multiple small, robust and inexpensive robot systems to neutralize UXO area.