waashk/dblp huggingface dataset:
mathematical modeling and experimental identification of an unmanned helicopter robot with flybar dynamics. this paper presents a mathematical model for a model-scale unmanned helicopter robot, with emphasis on the dynamics of the flybar. the interaction between the flybar and the main rotor blade is explained in detail; it is shown how the flapping of the flybar increases the stability of the helicopter robot as well as assists in its actuation. the model helicopter has a fast time-domain response due to its small size, and is inherently unstable. therefore, most commercially available model helicopters use the flybar to augment stability and make it easier for a pilot to fly. working from first principles and basic aerodynamics, the equations of motion for full six degree-of-freedom with flybar-degree of freedom are derived. system identification experiments and results are presented to verify the mathematical model structure and to identify model parameters such as inertias and aerodynamic constants. &copy; 2004 wiley periodicals, inc.
design and control of a four-wheeled omnidirectional mobile robot with steerable omnidirectional wheels. omnidirectional mobile robots are capable of arbitrary motion in an arbitrary direction without changing the direction of wheels, because they can perform 3 degree-of-freedom (dof) motion on a two-dimensional plane. in this research, a new class of omnidirectional mobile robot is proposed. since it has synchronously steerable omnidirectional wheels, it is called an omnidirectional mobile robot with steerable omnidirectional wheels (omr-sow). it has 3 dofs in motion and one dof in steering. one steering dof can function as a continuously variable transmission (cvt). cvt of the omr-sow increases the range of velocity ratio from the wheel velocities to robot velocity, which may improve performance of the mobile robot. the omr-sow with four omnidirectional wheels has been developed in this research. kinematics and dynamics of this robot will be analyzed in detail. various tests have been conducted to demonstrate the validity and feasibility of the proposed mechanism and control algorithm. &copy; 2004 wiley periodicals, inc.
dynamic process programming for a robotic manipulator based on hopfield nn monotonous optimization searching. a new approach to programming the optimal dynamic process for an n-joint rigid robotic manipulator with the use of the monotonous optimization searching ability of a hopfield nn is presented. by combining robotic dynamics, this paper designs a programmed controller, which satisfies the aforementioned dynamic process. the convergence of the programmed controller is investigated. simulations and experiments demonstrate the effectiveness of the scheme described. &copy; 2004 wiley periodicals, inc.
rider's net moment estimation using control force of motion system for bicycle simulator. one of the challenging problems with bicycle simulators is to deal with the virtual bicycle dynamics that is coupled with rider's motion. for the virtual bicycle dynamics calculation and the real time simulation, it is necessary to identify the control inputs from the rider as well as the virtual environments. the steering, pedaling, and braking torques can be easily measured by using torque sensors and the virtual environments can be generated and provided by a visual system. however, direct measurement of the rider's net moment that significantly affects the bicycle motion is not practical. in this work, it is shown that six control forces of the stewart platform-based motion system can be used for effective estimation of the rider's net moment, incorporated with the sliding mode controller with perturbation estimation. &copy; 2004 wiley periodicals, inc.
formation of a geometric pattern with a mobile wireless sensor network. mobile wireless sensor networks (mwsns) will enable information systems to gather detailed information about the environment on an unprecedented scale. these self-organizing, distributed networks of sensors, processors, and actuators that are capable of movement have a broad range of potential applications, including military reconnaissance, surveillance, planetary exploration, and geophysical mapping. in many of the foreseen applications, the mwsn will need to form a geometric pattern without assistance from the user. in military reconnaissance, for example, the nodes will be dropped onto the battlefield from a plane and land at random positions. the nodes will be expected to arrange themselves into a predetermined formation in order to perform a specific task. thus, we present algorithms for forming a line, circle, and regular polygon from a given set of random positions. the algorithms are distributed and use no communication between the nodes to minimize energy consumption. unlike past studies of geometric problems where algorithms are either tested in simulations where each node has global knowledge of all the other nodes or implemented on a small number of robots, the robustness of our algorithms has been studied with simulations that model the sensor system in detail. the simulations demonstrate that the algorithms are robust against random errors in the sensors and actuators. &copy; 2004 wiley periodicals, inc.
a distributed fuzzy logic controller for an autonomous vehicle. autonomous vehicles can be used in a variety of applications such as hazardous environments or intelligent highway systems. fuzzy logic is an appropriate choice for this application as it can describe human behavior well. this paper proposes two fuzzy logic controllers for the steering and the velocity control of an autonomous vehicle. the two controllers are divided into separate modules to mimic the way humans think while driving. the steering controller is divided into four modules; one module drives the vehicle toward the target while another module avoids collision with obstacles. a third module drives the vehicle through mazes. the fourth module adjusts the final orientation of the target. the velocity controller is divided into three modules; the first module speeds up the vehicle to reach the target and slows it down as it moves toward the target. the second module controls the velocity in the neighborhood of obstacles. a third module controls the velocity of the vehicle as it turns sharp corners. a method for automatic tuning of the first module of the velocity controller is proposed to stabilize the velocity of the vehicle as it approaches the target. two examples to demonstrate the interaction among the seven control modules are included. results of the simulation are compared with those in the literature. &copy; 2004 wiley periodicals, inc.
omnidirectional vision and inertial clues for robot navigation. the structural features inherent in the visual motion field of a mobile robot contain useful clues about its navigation. the combination of these visual clues and additional inertial sensor information may allow reliable detection of the navigation direction for a mobile robot and also the independent motion that might be present in the 3d scene. the motion field, which is the 2d projection of the 3d scene variations induced by the camera-robot system, is estimated through optical flow calculations. the singular points of the global optical flow field of omnidirectional image sequences indicate the translational direction of the robot as well as the deviation from its planned path. it is also possible to detect motion patterns of near obstacles or independently moving objects of the scene. in this paper, we introduce the analysis of the intrinsic features of the omnidirectional motion fields, in combination with gyroscopical information, and give some examples of this preliminary analysis. &copy; 2004 wiley periodicals, inc.
a new space and time sensor fusion method for mobile robot navigation. to fully utilize the information from the sensors of mobile robot, this paper proposes a new sensor-fusion technique where the sample data set obtained at a previous instant is properly transformed and fused with the current data sets to produce a reliable estimate for navigation control. exploration of an unknown environment is an important task for the new generation of mobile service robots. the mobile robots may navigate by means of a number of monitoring systems such as the sonar-sensing system or the visual-sensing system. notice that in the conventional fusion schemes, the measurement is dependent on the current data sets only. therefore, more sensors are required to measure a given physical parameter or to improve the reliability of the measurement. however, in this approach, instead of adding more sensors to the system, the temporal sequences of the data sets are stored and utilized for the purpose. the basic principle is illustrated by examples and the effectiveness is proved through simulations and experiments. the newly proposed stsf (space and time sensor fusion) scheme is applied to the navigation of a mobile robot in an environment using landmarks, and the experimental results demonstrate the effective performance of the system. &copy; 2004 wiley periodicals, inc.
a new immune genetic algorithm and its application in redundant manipulator path planning. in this paper, first the immune system is analyzed in a relatively deeper and all-sided point of view reflecting the fresh research in biology. second, based on the previous statements, a new optimization method, the immune genetic algorithm (iga), is presented by simulating the behavior of the biological immune system and is proved to converge to the global optimum with probability 1. third, a new method on the multi-object optimization that is transformed into a single-object one is proposed based on the joints' best compliance in the redundant robot path planning using iga. last, the experiment results show that the method of this article behaves more successfully. &copy; 2004 wiley periodicals, inc.
fusing visual and inertial sensing to recover robot ego-motion. a method for estimating mobile robot ego-motion is presented, which relies on tracking contours in real-time images acquired with a calibrated monocular video system. after fitting an active contour to an object in the image, 3d motion is derived from the affine deformations suffered by the contour in an image sequence. more than one object can be tracked at the same time, yielding some different pose estimations. then, improvements in pose determination are achieved by fusing all these different estimations. inertial information is used to obtain better estimates, as it introduces in the tracking algorithm a measure of the real velocity. inertial information is also used to eliminate some ambiguities arising from the use of a monocular image sequence. as the algorithms developed are intended to be used in real-time control systems, considerations on computation costs are taken into account. &copy; 2004 wiley periodicals, inc.
black knight: an autonomous vehicle for competition. black knight, the university of central florida's vehicle in the 11th intelligent ground vehicle competition (igvc) competed in 2003. completing in 5th place in the navigational challenge and 10th in the autonomous challenge in its first competition has proven our vehicle to be a strong competitor in this competition. the vehicle has many interesting features that allow it to achieve its success. the vehicle's 300 lb. capacity allows for two onboard full-sized computers and two 12 v marine batteries that power the computers for up to 2 h. the vision system is not a simple reactive system but rather it classifies its view into objects and builds a map of the territory as it learns of its features while traveling. two transformations and the location data from the gps and other sensors are used to associate the locations in the image to locations in the map. the operations of the vehicle are modeled after the typical operations of a ship. we have programs that perform the functions of the captain, the helm, the navigator, and the engineer. in addition we have a program performing sensor data fusion from the gps, compass, and wheel encoder data. the navigation uses an adapted two-dimensional approximate cell decomposition method that satisfies the nonholononic constraints of our vehicle and allows it to find the shortest path to the goal while avoiding all obstacles. &copy; 2004 wiley periodicals, inc.
design of an unmanned ground vehicle, bearcat iii, theory and practice. the purpose of this paper is to describe the design and implementation of an unmanned ground vehicle, called the bearcat iii, named after the university of cincinnati mascot. the bearcat iii is an electric powered, three-wheeled vehicle that was designed for the intelligent ground vehicle competition and has been tested in the contest for 5 years. the dynamic model, control system, and design of the sensory systems are described. for the autonomous challenge line following, obstacle detection and pothole avoidance are required. line following is accomplished with a dual camera system and video tracker. obstacle detection is accomplished with either a rotating ultrasound or laser scanner. pothole detection is implemented with a video frame grabber. for the navigation challenge waypoint following and obstacle detection are required. the waypoint navigation is implemented with a global positioning system. the bearcat iii has provided an educational test bed for not only the contest requirements but also other studies in developing artificial intelligence algorithms such as adaptive learning, creative control, automatic calibration, and internet-based control. the significance of this effort is in helping engineering and technology students understand the transition from theory to practice. &copy; 2004 wiley periodicals, inc.
an autonomous tracked vehicle with omnidirectional sensing. operation of an autonomous vehicle along a marked path, in an obstacle-laden environment, requires path detection, relative position detection and control, and obstacle detection and avoidance. the design solution of the team from the u.s. military academy is a tracked vehicle operating open-loop in response to position information from an omnidirectional mirror, and to obstacle-detection input from the mirror and from a scanning laser. the use of a tracked rather than a wheeled vehicle is the team's open-loop solution to the problem of wheeled-vehicle slippage on wet and sandy surfaces. the vehicleresponds to sensor information from (1) a digital camera-mounted parabolic omnidirectional mirror for visual inputs and (2) a scanning laser for detecting obstacles in relief. raw sensor data is converted synchronously into a global virtual context, which places the vehicle's center at the origin of a 2-d cartesian coordinate system. a four-phase process is used to convert the camera's inputs into the data structures needed to reason about the vehicle's position relative to the course. development of the path plan proceeds incrementally, using a space-sweeping algorithm to identify safe paths along waypoints within the course boundaries. an attempt is made to minimize translation errors by favoring paths which exhibit fewer sharp turns. integration of intel's opencv computer vision library and the independent jpeg group's jpeg library allow for very good encapsulation of the low-level functions needed to do most of the image processing. ada95 is the language of choice for the majority of the team-developed software, except where needed to interface to motors and sensors. use of an object-oriented high-level language has been invaluable in leveraging the efforts of previous years' development activities, and for maximizing the ability to log or otherwise respond to anomalous behavior. &copy; 2004 wiley periodicals, inc.
principles of fusion of inertial navigation and dynamic vision. the possibility of fusion of navigation data obtained by two separate navigation systems (strap-down inertial one and dynamic vision based one) is considered in this paper. the attention is primarily focused on principles of validation of separate estimates before their use in a combined algorithm. the inertial navigation system (ins) based on sensors of medium level quality has been analyzed on one side, while a visual navigation method is based on the analysis of a sequence of images of ground landmarks produced by an on-board tv camera. the accuracy of ins estimations is being improved continuously by optimal estimation of a flying object's angular orientation while the visual navigation system offers discrete corrections during the intervals of presence of landmarks inside the camera's field of view. the concept is illustrated by dynamic simulation of a realistic flight scenario. &copy; 2004 wiley periodicals, inc.
inertial sensed ego-motion for 3d vision. inertial sensors attached to a camera can provide valuable data about camera pose and movement. in biological vision systems, inertial cues provided by the vestibular system are fused with vision at an early processing stage. in this article we set a framework for the combination of these two sensing modalities. cameras can be seen as ray direction measuring devices, and in the case of stereo vision, depth along the ray can also be computed. the ego-motion can be sensed by the inertial sensors, but there are limitations determined by the sensor noise level. keeping track of the vertical direction is required, so that gravity acceleration can be compensated for, and provides a valuable spatial reference. results are shown of stereo depth map alignment using the vertical reference. the depth map points are mapped to a vertically aligned world frame of reference. in order to detect the ground plane, a histogram is performed for the different heights. taking the ground plane as a reference plane for the acquired maps, the fusion of multiple maps reduces to a 2d translation and rotation problem. the dynamic inertial cues can be used as a first approximation for this transformation, allowing a fast depth map registration method. they also provide an image independent location of the image focus of expansion and center of rotation useful during visual based navigation tasks. &copy; 2004 wiley periodicals, inc.
autonomous ground vehicle path tracking. autonomous ground vehicle navigation requires the integration of many technologies such as path planning, position and orientation sensing, vehicle control, and obstacle avoidance. the work presented here focuses on the control of a nonholonomic ground vehicle as it tracks a given path. a new path tracking technique called &ldquo;vector pursuit&rdquo; is presented. this new technique is based on the theory of screws, which was developed by sir robert ball in 1900. it generates a desired vehicle turning radius based on the vehicle's current position and orientation relative to the position of a point ahead on the planned path and the desired orientation along the path at that point. the vector pursuit algorithm is compared to other geometrical approaches, and it is shown to be more robust, resulting in more accurate path tracking. &copy; 2004 wiley periodicals, inc.
serpent. standardization is one of the hallmarks of an industrial society. as a society becomes increasingly complex and its industrial base begins to emerge, it becomes necessary for the products, processes, and procedures of the society to fit together and to interoperate. this interoperation provides the basis for greater integration of the elements of the society, which in turn causes increased social interdependency and complexity. this trend has recently been accelerated by the so-called "global economy," and further spurred by the creation of seamless methods of transnational transfer of information and knowledge via the the internet (q.v.) and the world wide web (q.v.). both the internet and the web are currently based entirely upon voluntary standardization. their result is increased information interdependence, which in turn will feed the need for increased application standardization. however, the standardization that will result from the application of these technologies will include social and economic standardization, a phenomenon whose depth and implications are just now beginning to be appreciated.
data remanence. something is wrong, now what: this article will help you figure out what went wrong, how to get started on fixing it, or now to prepare for possible crashes.
mars. graphic artists have a wide variety of applications to use for digital painting. although each application has its own solution to enhance the user experience, most of them rely on the same standard feature; a single brush, which is completely dependent on user input for location. although this is required for a fully controlled painting process, making small changes on this feature yields unpredictable results. my proposal for an alternate brush paradigm is using multiple brushes (as seen in the application "pd particles"), which are not completely under control but rather moving within trajectories with random deviations, simultaneously. the trajectories are defined by controllable parameters and the user input. since the rate of obedience to user input is dependant on the parameters, users can define the rate of deviation and thus switch between finger painting and generative painting, without changing the set of tools.
compromising emanations. cybernetic concepts and design implications can be elucidated by means of computer experiments. a series of programs have been prepared which simulate the operation of typical control devices. the system of interest is first studied under uncontrolled conditions using typical input data for the process under study. the system is then &ldquo;connected&rdquo; to chosen control elements such as feedback transducers, comparitors and controllers. in a biological context homeostatic adjustment is considered as a function of the control parameters. transient response is noted as processes are switched on and off. regulatory conditions are determined by the goal state to maintain bounds on fluctuations or give rise to stable oscillatory cycles. sensitivity analysis is carried out with respect to competing control elements. the role of response lag is clearly demonstrated by simultaneous graphing of related state variables. only after the response of basic elements is ascertained are they joined in complex configurations. in this manner the behavior of a complex structure is understood in terms of its underlying elements.
birthday paradox. this paper focuses on art created by new techniques such as cellular machines, l-systems, genetic algorithms, neural networks ... we propose here several methods of implementation combining the rules of construction of cellular machines and l-systems with genetic, neuronal networks, couplings, translation of codes. these methods result in the morphogenesis of bodies, as well their structure (shape) and their functional aspect (neuronal networks with driving, sensory neurons, balance, etc.). it's a part of what we can call "a new kind of art", and we can see here how beings-paintings emerge.
sender anonymity. all complex systems fail, by some measure of the word "fail," with consequences ranging from benign to catastrophic. this article examines the process of to triage in the face of a failing system.