The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
This paper introduces a motion planning method for a rapid mobile manipulator using an inverted pendulum model. We design a linear quadratic optimal controller to stabilize ZMP. The two kinds of ZMP stabilization strategies (Fixed ZMP and Relaxed ZMP) are proposed. The highly geared manipulator is controlled by a Cartesian computed torque (CCT) control for compliant motion. A rapid mobile manipulator...
Semiconductor manufacturing fabs recently tend to reduce the lot size, that is, the number of identical wafers in a lot, because of small lot orders and increased die throughput per wafer due to wafer size increase. Therefore, cluster tools for wafer processing, which mostly repeat identical work cycles, are subject to frequent lot changes. We therefore examine scheduling problems for transient periods...
Probabilistic planners such as Rapidly-Exploring Random Trees (RRTs) and Probabilistic Roadmaps (PRMs) are powerful path planning algorithms for high dimensional systems, but even these potent techniques suffer from the curse of dimensionality, as can be seen in multirobot systems. In this paper, we apply a technique called subdimensional expansion in order to enhance the performance of probabilistic...
This paper presents a hybrid mechanical model for the Gibbot, a robot that dynamically locomotes along a vertical wall in a manner analogous to gibbons swinging between branches in the forest canopy. We focus on one particular gait, continuous-contact brachiation, which always has one handhold in contact with the wall. We use zero-cost, unstable solutions corresponding to horizontal brachiation, originally...
Bipedal robots are currently either slow, energetically inefficient and/or require a lot of control to maintain their stability. This paper introduces the FastRunner, a bipedal robot based on a new leg architecture. Simulation results of a Planar FastRunner demonstrate that legged robots can run fast, be energy efficient and inherently stable. The simulated FastRunner has a cost of transport of 1...
This paper reports the design requirements, practical challenges, and a preliminary design for a magnetic resonance imaging (MRI) guided, three degree-of-freedom (DOF) transrectal prostate intervention robot. We show the operational space constraints imposed by patient anatomy when performing transrectal prostate procedures in a magnetic resonance (MR) scanner bore, as determined by analyzing data...
This paper presents Optimally Scaled Hip-Force Planning (OSHP), a novel approach to controlling the body dynamics of running robots. Controllers based on OSHP form the high-level component of a hierarchical control scheme in which they direct lower level controllers, each responsible for coordinating the motion of a single leg. An OSHP controller takes in the state of the runner at the apex of its...
In this work we present principled methods for the coordination of a robot's oculomotor system with the rest of its body motor systems. The problem is to decide which physical actions to perform next and where the robot's gaze should be directed in order to gain information that is relevant to the success of its physical actions. Previous work on this problem has shown that a reward-based coordination...
Interaction with its environment is a key requisite for a humanoid robot. Especially the ability to recognize and manipulate unknown objects is crucial to successfully work in natural environments. Visual object recognition, however, still remains a challenging problem, as three-dimensional objects often give rise to ambiguous, two-dimensional views. Here, we propose a perception-driven, multisensory...
Light Detection and Ranging (LIDAR) scans are increasingly being used for 3D map construction and reverse engineering. The utility and benefit of the processed data maybe enhanced if the objects and geometry of the area scanned can be segmented and labeled. In this paper, we present techniques to model the intensity of the laser reflection return from a point during LIDAR scanning to determine diffuse...
We consider the partially observable control problem where it is potentially necessary to perform complex information-gathering operations in order to localize state. One approach to solving these problems is to create plans in belief-space, the space of probability distributions over the underlying state of the system. The belief-space plan encodes a strategy for performing a task while gaining information...
In this paper, we study the problem of Cooperative Localization (CL) for two robots, each equipped with an Inertial Measurement Unit (IMU) and a camera. We present an algorithm that enables the robots to exploit common features, observed over a sliding-window time horizon, in order to improve the localization accuracy of both vehicles. In contrast to existing CL methods, which require robot-to-robot...
Pick-place of single nanowires inside scanning electron microscopes (SEM) is useful for prototyping functional devices and characterizing nanowires' properties. Nanowire pick-place has been typically performed via teleoperation, which is time-consuming and highly skill-dependent. This paper presents a robotic system capable of automated pickplace of single nanowires. Through SEM visual detection and...
To explore or exploit? In this paper, we discuss the long-standing exploration-exploration dilemma in context of designing a learning controller for stunt-style driving with scarce samples. By making an efficient use of a single demonstration by an expert, our algorithm leverages our intuitive understanding of driving to extract a coarse dynamics model from the collected driving data, then formulate...
We present a general method of estimating a snake robot's motion over flat ground using only knowledge of the robot's shape changes over time. Estimating world motion of snake robots is often difficult because of the complex way a robot's cyclic shape changes (gaits) interact with the surrounding environment. By using the virtual chassis to separate the robot's internal shape changes from its external...
This paper introduces a new simplified static analysis of parallel robots driven by inextensible cables of non-negligible mass. It is based on a known hefty cable static modeling which seems to have been overlooked in previous works on parallel cable-driven robots. This cable modeling is obtained from a well-known sagging cable modeling, known as the catenary, by assuming that cable sag is relatively...
We present a technique to estimate the egomotion of an RGB-D sensor based on rotations of functions defined on the unit sphere. In contrast to traditional approaches, our technique is not based on image features and does not require correspondences to be generated between frames of data. Instead, consecutive functions are correlated using spherical harmonic analysis. An Extended Gaussian Image (EGI),...
We present an ensemble framework for the design of distributed control and communication strategies for the dynamic allocation of a team of robots to a set of tasks. In this work, we assume individual robot controllers are sequentially composed of individual task controllers. This assumption enables the representation of the robot ensemble dynamics as a class of stochastic hybrid systems that can...
Grasping has been studied from various perspectives including planning, control, and learning. In this paper, we take a learning approach to predict successful grasps for a universal jamming gripper. A jamming gripper is comprised of a flexible membrane filled with granular material, and it can quickly harden or soften to grip objects of varying shape by modulating the air pressure within the membrane...
The tasks robots are employed to achieve are becoming increasingly complex, demanding for dependable operation, especially if robots and humans share common space. Unfortunately, for these robots non-determinism is a severe challenge. Malfunctioning hardware, inaccurate sensors, exogenous events and incomplete knowledge lead to inconsistencies in the robot's belief about the world.
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.