Ground Mobile Robots Research Articles

Cooperative Target Tracking Control of Multiple Robots

This paper focuses on the problem of moving target tracking with a group of mobile robots. Each robot in the group has a pan/tilt camera to detect the target and has limited communication capability to communicate with neighbor robots. The problem is solved by separating it into two parts. One part is the estimation of target position and another is the flocking control of multiple robots moving toward the estimated position. In the target estimation part, we propose to use a novel distributed Kalman filter to estimate the target position. The distributed Kalman filter is deduced based on a standard Kalman filter by modeling the neighbor's information as one of measurements. In the motion control part, a distributed flocking algorithm is developed. It is used to track the estimated target and avoid collision. In both parts, only local communication between neighbor robots is required. Finally, the tracking algorithms are simulated with 2-D and 3-D robots to verify their performance. The simulation results provide a firm conclusion that the proposed algorithms are able to track a moving target. A group of real ground mobile robots is used to test the proposed algorithm. The experiment results show that multiple robots are able to cooperate to track the target under the proposed algorithms and the tracking result outperforms the result produced by individual robots without cooperation.

Review article: locomotion systems for ground mobile robots in unstructured environments

Abstract. The world market of mobile robotics is expected to increase substantially in the next 20 yr, surpassing the market of industrial robotics in terms of units and sales. Important fields of application are homeland security, surveillance, demining, reconnaissance in dangerous situations, and agriculture. The design of the locomotion systems of mobile robots for unstructured environments is generally complex, particularly when they are required to move on uneven or soft terrains, or to climb obstacles. This paper sets out to analyse the state-of-the-art of locomotion mechanisms for ground mobile robots, focussing on solutions for unstructured environments, in order to help designers to select the optimal solution for specific operating requirements. The three main categories of locomotion systems (wheeled – W, tracked – T and legged – L) and the four hybrid categories that can be derived by combining these main locomotion systems are discussed with reference to maximum speed, obstacle-crossing capability, step/stair climbing capability, slope climbing capability, walking capability on soft terrains, walking capability on uneven terrains, energy efficiency, mechanical complexity, control complexity and technology readiness. The current and future trends of mobile robotics are also outlined.

Design and Realization of the Mobile Robot with Caterpillar Double Accused for Extinguishing

In this paper, two kinds modes of the mobile robot made fire caterpillar method are presented, manual control and automatic control,can this not only make it have the performance of the movement in cross-country, but also realize the early warning and effective extinguishing the fire by carrying the flame using sensors and connecting rod type fire extinguishing actuators.This paper introduce the robot structure design, fire extinguishing actuators, control system design, operation analysis and the realization of two-way control mode , provide the reference for minitype ground mobile robot and the related technology research.

Fuzzy control of an underactuated pendulum-driven cart system

This paper proposes a fuzzy control (FC) algorithm for a pendulum-driven cart (PDC) system. The PDC is a mechanism that represents a novel driving concept of ground mobile robot which only employs internal thrust and static friction. The control objective of the system is to drive the cart towards a desired direction by swinging the pendulum only. The proposed FC algorithm is designed based on the closed-loop control algorithm proposed in Yu et al. (2008a). Simulation results are presented to demonstrate the effectiveness of the proposed algorithm. A prototype of the PDC system developed by using the LEGO Mindstorms kit and the ROBOLAB Software is also presented in the paper. The experimental results demonstrate that the PDC system is realisable, and the proposed FC algorithm is simple and effective.

Virtual Target based Path-Following Guidance System for Cooperative USV Swarms

This paper focuses on the integration of a cooperative swarm methodology initially developed for small ground mobile robots, with a virtual target based path-following guidance system developed for marine surface vehicle systems. After separately describing the approaches, for swarm aggregation and path-following guidance respectively, the paper reports the effortless procedure to perform the integration of the proposed techniques. Simulative and experimental results are then proposed to prove the effectiveness of the proposed methodology.

Modelling and motion control of a double-pendulum driven cart

The significant advantage of ground mobile robots (GMRs) is their accessibility to areas that are inaccessible for humans. One difficulty of current GMR technology is that the external driving mechanisms, such as wheel, track, and leg, restrict its applications. In order to solve this limitation, the present paper proposes a novel driving mechanism using a novel GMR called the double-pendulum driven cart (DPDC). The DPDC, which employs only internal thrust and static friction, is capable of steering by two parallel pendulums mounted on the cart, and is able to implement planar elemental motions by designing the pendulum trajectory properly. The paper first studies the dynamic modelling and the motion control issues of the DPDC. A closed-loop controller using the partial feedback linearization technique is then designed for the tracking control of the parallel pendulums to guarantee accurate motion of the cart. Extensive simulation results verify the proposed model and the efficiency of the motion control strategy.

Data Structures for Efficient Dynamic Processing in 3-D

This paper considers the problem of the dynamic processing of large amounts of sparse three-dimensional data. It is assumed that computations are performed in a neighborhood defined around each point in order to retrieve local properties. This general kind of processing can be applied to a wide variety of problems. A new, efficient data structure and corresponding algorithms are proposed that significantly improve the speed of the range search operation and that are suitable for on-line operation where data is accumulated dynamically. The method relies on taking advantage of overlapping neighborhoods and the reuse of previously computed data as the algorithm scans each data point. To demonstrate the dynamic capabilities of the data structure, data obtained from a laser radar mounted on a ground mobile robot operating in complex, outdoor environments is used. It is shown that this approach considerably improves the speed of an established 3-D perception processing algorithm.

Mosaic-based 3D scene representation and rendering

In this paper we address the problem of fusing images from many video cameras or a moving video camera. The captured images have obvious motion parallax, but they will be aligned and integrated into a few mosaics with a large field-of-view (FOV) that preserve 3D information. We have developed a compact geometric representation that can re-organize the original perspective images into a set of parallel projections with different oblique viewing angles. In addition to providing a wide field of view, mosaics with various oblique views well represent occlusion regions that cannot be seen in a usual nadir view. Stereo mosaic pairs can be formed from mosaics with different oblique viewing angles. This representation can be used as both an advanced interface for interactive 3D video and a pre-processing step for 3D reconstruction. A ray interpolation approach for generating the parallel-projection mosaics is presented, and efficient 3D scene/object rendering based on multiple parallel-projection mosaics is discussed. Several real-world examples are provided, with applications ranging from aerial video surveillance/environmental monitoring, ground mobile robot navigation, to under-vehicle inspection.

Supervisory control of mobile sensor networks: math formulation, simulation, and implementation

This paper uses a novel discrete-event controller (DEC) for the coordination of cooperating heterogeneous wireless sensor networks (WSNs) containing both unattended ground sensors (UGSs) and mobile sensor robots. The DEC sequences the most suitable tasks for each agent and assigns sensor resources according to the current perception of the environment. A matrix formulation makes this DEC particularly useful for WSN, where missions change and sensor agents may be added or may fail. WSN have peculiarities that complicate their supervisory control. Therefore, this paper introduces several new tools for DEC design and operation, including methods for generating the required supervisory matrices based on mission planning, methods for modifying the matrices in the event of failed nodes, or nodes entering the network, and a novel dynamic priority assignment weighting approach for selecting the most appropriate and useful sensors for a given mission task. The resulting DEC represents a complete dynamical description of the WSN system, which allows a fast programming of deployable WSN, a computer simulation analysis, and an efficient implementation. The DEC is actually implemented on an experimental wireless-sensor-network prototyping system. Both simulation and experimental results are presented to show the effectiveness and versatility of the developed control architecture.

Winning the DARPA Grand Challenge

The DARPA Grand Challenge was the most significant event in the field of robotics in more than a decade. A mobile ground robot had to traverse 131 miles of punishing desert terrain in less than ten hours. In 2004, the best robot only made 7.3 miles. A year later, Stanford's robot Stanley won this historical challenge, and the Stanford Racing Team cashed the $2M prize

Visual motion planning for mobile robots

This paper presents a novel framework for image-based motion planning, which we term Visual Motion Planning. The method skips the step of transferring image features back to robot pose, and hence makes motion plans directly in the image plane. Analogous to visual servo control, the visual motion planning concept takes advantage of the image features to achieve a direct and fast motion planning solution. It provides a virtual trajectory in the image plane for the robot to track with standard visual servoing techniques. In this paper, we show the result of applying the idea to simulated 2-D and 3-D mobile robot systems. Within this motion planning paradigm, we also discuss the mechanisms for taking advantage of surplus features and incorporating image-based constraints, such as requiring that the images remain in the field of view. Experimental results using a Pioneer AT ground mobile robot are presented, showing excellent agreement with theory.

Special Issue on Current Status and Prospects of Amusement Robots

Manipulating robots that have been developed to replace the functions of human hands have successfully achieved the objectives of industrial robots; more than 400,000 of such robots are currently in operation, primarily in production lines of factories worldwide. Furthermore, robots with locomotive functions, i.e. autonomous ground vehicles and mobile robots, are being widely used in both production and non-production environments. Actually a great number of mobile robots are operating in non-production environments. Examples are robots for service applications in offices, hospitals, and homes; safety guard robots; maintenance and supervision robots; firefighting robots; emergency rescue robots; hazard prevention robots; space robots; and educational robots. These robots, whether they are intended for production or non-production use, make a significant contribution to mankind by performing some useful jobs or by accomplishing some useful duties in place of humans; thus, relieving humans of hard labor. In addition to the above robots, researchers, have developed many robots that belong to the conceptual classification of amusement robots. These robots do not perform any useful work or tasks in place of humans; however, they amuse the people who watch them play games or who manipulate them. Many automata that imitate the actions of humans have been developed both in Europe and in Japan. Such robots can be considered as prototypes of amusement robots. Included in the anthropomorphic automata developed in Europe are automatic puppets that play musical instruments, write letters, or draw pictures, dance, or something of the like. Similarly in Japan, since approximately 300 years ago, various types of automata called karakuri-puppets have been developed, and these puppets fascinate naive audiences even today by playing elegant dramas or performing some acrobatic feats at festivals held at shrines and temples. In Japan in 1796, Yorinao Hosokawa published an excellent technical book on the mechanisms and design of the karakuri-puppets. Today, thanks to the progress of microcomputers, a large number of performance robots have been developed that replace the functions of human being and animals or can perform behaviors that no animate creatures can do. Various types of robot contests have already been held including micromouse, tennis matches, ball-collection contests, and water-dipping contests. It is expected that international robot Olympiads for the contests of advanced technology and intelligence are expected to be held in the future. The progress of contest robots of the highest technical level will contribute to the progress of robot technology. People of all ages, from infants to old men and women, would be able to entertain themselves by playing with robots and could share emotion with the robots if people can develop various types of such amusement robots that can appeal to the feelings of people. Furthermore, robots can provide people with mental satisfaction as well as can be the consultants and friends of them. Amusement robots must stimulate the imaginations of young researchers, contributing to the progress of robotics. Consequently, the development of robots that are extremely similar to human being will be the next target.