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This paper presents an approach to accurate and scalable multiple-model (MM) state estimation for hybrid systems with intermittent, cyclical, multimodal dynamics. The approach consists of using discrete-state estimation to identify a system’s dynamical and behavioral contexts and determine which motion models appropriately represent current dynamics and which individual and MM filters are appropriate for state estimation. Furthermore, the heirarchical structure of the dynamics is explicitly encoded, which enables detection not only of rapid transitions between motion models but of higher level behavioral transitions as well. This improves the accuracy and scalability of conventional MM state estimation, which is demonstrated experimentally on a mobile robot that exhibits fast-switching, multimodal dynamics. [ABSTRACT FROM AUTHOR]

This paper addresses the coupled navigation and control problem for fully actuated dynamical systems operating in cluttered environments. The proposed method composes local feedback control policies to address the global problem in a formally correct manner. Our contribution extends the method of sequential composition to a new class of flow-through policies, which are defined for an idealized point robot that is subject to bounds on velocity and acceleration. These policies, which are defined over convex polytopes, express natural behaviors and guarantee safe trajectories while respecting system constraints. This paper presents a constructive technique for building hybrid control systems with guaranteed transitions and stability properties. Simulation results demonstrate policy-based decision making for various initial conditions. [ABSTRACT FROM AUTHOR]

Complete automation of trajectory planning tools for material deposition/removal applications has become increasingly necessary to reduce the "concept-to-consumer" timeline for rapid product introduction in industries such as the automotive industry. The work in this paper is specifically motivated by automotive spray painting. Prior developments in automated trajectory planning tools promise to reduce the time required to program the robots; however, these approaches are limited to surfaces that are either approximately planar or topologically simple (i.e., with no holes). To extend the applicability of these planning tools to nonplanar and topologically complex surfaces, currently the user has to manually segment a complex surface into simpler subsets, i.e., subsets that are approximately extruded surfaces and contain no holes. However, the complex nature of the relationships between surface segmentation and resulting output characteristics such as material deposition uniformity, process cycle time, and material waste makes the task of manually segmenting the surface difficult. In this paper, we develop a hierarchical procedure that automatically segments a surface based on surface geometry, surface topology, and path geometry to obtain topologically simple subsets that are approximately extruded surfaces. Finally, we compare the effectiveness of our segmentation with the state of the art on a few automotive surfaces in simulation. Note to Practitioners--The surface segmentation strategies described in this work can be applied to surfaces that are composed of approximately extruded surface patches joined together by regions of high curvature; such surfaces include typical automotive surfaces. The segmentation procedure allows the user to automatically generate a collection of preliminary coverage trajectories. With careful selection and minor clean up, these trajectories can improve the coverage uniformity for a given surface. The procedure operates on a surface CAD model, preferably in the triangulated manifold format and requires information about the material distribution (or removal) pattern produced from the atomizer (or machining) tool. With an understanding of the relative costs associated with different output characteristics such as uniformity of deposition, cycle time, and material waste, the procedures can be incorporated in existing industrial planning and simulation toots (with appropriate support from the software vendor) for applications such as robotic spray painting and CNC machining. [ABSTRACT FROM AUTHOR]

The article discusses the development of the mechanical system of the actuator with mechanically adjustable series compliance (AMASC), a prototype leg for a running robot. It is said to be important to begin a robot design with a specification for the dynamic behavior of the machine, since the mechanical system cannot be changed easily once it is built. In this case, the actuator was designed to be equipped with mechanical springs, which will store and release kinetic energy as it follows a center-of-mass motion during a running gait. Based on the design of the AMASC, a single prototype leg of the BiMASC was designed and developed, which was eventually revised into the ECD leg.

The article reports on the decentralized multiagent traffic coordination approach in multirobotics system using a conventional Ackermann-steered vehicles. The approach uses low-level continuous feedback control policies that are combined with a correct distinct automation, which satisfies specified high-level behavior for any initial stage in the domain of low-level policies. It combines the strengths of control theoretic and computer science approaches, which offers guarantees that can be proven over local domains. The approach creates a hybrid-feedback-control policy that fulfills a given high-level specification without planning a specific configuration path by using a collection of local feedback control polices that provides continuous guarantees.

This research is focused on developing trajectory planning tools for the automotive painting industry. The geometric complexity of automotive surfaces and the complexity of the spray patterns produced by modern paint atomizers combine to make this a challenging and interesting problem. This paper documents our efforts to develop computationally tractable analytic deposition models for electrostatic rotating bell (ESRB) atomizers, which have recently become widely used in the automotive painting industry. The models presented in this paper account for both the effects of surface curvature as well as the deposition pattern of ESRB atomizers in a computationally tractable form, enabling the development of automated trajectory generation tools. We present experimental results used to develop and validate the models, and verify the interaction between the deposition pattern, the atomizer trajectory, and the surface curvature. Limitations of the deposition model with respect to predictions of paint deposition on highly curved surfaces are discussed. Note to Practitioners-The empirical paint deposition models developed herein, which are fit to experimental data, offer a significant improvement over models that are typically used in industrial robot simulations. The improved simulation results come without the computational cost and complexity of finite element methods. The models could be incorporated, as is, into existing industrial simulation tools, provided the users are cognizant of the model limitations with respect to highly curved surfaces. Although the models are based on readily available information, incorporating the models into existing robot simulation software would likely require support from the software vendor. [ABSTRACT FROM AUTHOR]

Presents a working implementation of a dynamics based architecture for visual sensing. Field rate estimates provided by the architecture; How the interconnection of two nonlinear dynamical systems affected the system's success.