Automatic Code Generation for Actuator Interfacing from a Declarative Specification

Abstract -Common software design practices use objectoriented (OO) frameworks that structure software in terms of objects, classes, and package; designers then create programs by inheritance and composition of classes and objects. Operational Software Components for Advanced Robotics (OSCAR) is one such framework for robot control software with abstractions for generalized kinematics, dynamics, performance criteria, decision making, and hardware interfacing. Even with OSCAR, writing new programs still requires a significant amount of manual labor. Feature-Oriented Programming (FOP) is method for software design that models and specifies programs in terms of features, where a feature encapsulates the common design decisions that occur in a domain. A set of features then forms a domain model for a Product Line Architecture. Product variants in this product line can then be generated from a declarative specification. FOP and related technologies are emerging software engineering techniques for automatically generating prorams. Our research applies FOP to robot controller software. As an example, the domain of hardware interfacing is analyzed and 41 features identified. A GUI for specifying and generating programs is presented as well. Analysis of features shows 200 possible different programs could be generated

1-[(6-Chloro­pyridin-3-yl)meth­yl]­imidazolidin-2-one

In the title mol­ecule, C9H10ClN3O, the dihedral angle between the pyridine ring and imidazoline ring mean plane [maximum deviation = 0.031–(3) Å] is 76.2 (1)°. In the crystal, N—H⋯O hydrogen bonds link pairs of mol­ecules to form inversion dimers. In addition, weak C—H⋯N hydrogen bonds and π–π stacking inter­actions between pyridine rings [centroid–centroid distance = 3.977 (2) Å] are observed

Ethyl 2-{3-[(6-chloro­pyridin-3-yl)meth­yl]-2-(nitro­imino)­imidazolidin-1-yl}acetate

In the title compound, C13H16ClN5O4, the imidazole ring is in a slight envelope conformation. The dihedral angle between the pyridine ring and the four essentially planar atoms [maximum deviation 0.015 (2) Å] of the imidazole ring is 80.8 (1)°. In, the crystal, weak C—H⋯O and C—H⋯N hydrogen bonds are present. In addition, there are weak π–π stacking inter­actions between symmetry-related pyridine rings with a centroid–centroid distance of 3.807 (1) Å

DETC2004-57447 MANIPULATOR TASK-BASED PERFORMANCE OPTIMIZATION

ABSTRACT This research uses new developments in redundancy resolution and real-time capability analysis to improve the ability of an articulated arm to satisfy task constraints. Task constraints are specified using numerical values of position, velocity, force, and accuracy. Inherent in the definition of task constraints is the number of output constraints that the system needs to satisfy. The relationship of this with the input space (degrees of freedom) defines the ability to optimize manipulator performance. This is done through a Task-Based Redundancy Resolution (TBRR) scheme that uses the extra resources to find a solution that avoids system constraints (joint limits, singularities, etc.) and satisfies task constraints. To avoid system constraints, we use well-understood criteria associated with the constraints. For task requirements, the robot capabilities are estimated based on kinematic and dynamic manipulability analyses. We then compare the robot capabilities with the userspecified requirement values. This eliminates a confusing chore of selecting a proper set of performance criteria for a task at hand. The breakthrough of this approach lies in the fact that it continuously evaluates the relationship between task constraints and system resources, and when possible, improves system performance. This makes it equally applicable to redundant and non-redundant systems. The scheme is implemented using an object-oriented operational software framework and its effectiveness is demonstrated in computer simulations of a 10-DOF manipulator

DETC2005-84353 REAL-TIME ROBOT CAPABILITY ANALYSIS

ABSTRACT Robot Capability Analysis (RCA) is a process in which force/motion capabilities of a manipulator are evaluated. It is very useful in both the design and operational phases of robotics. Traditionally, ellipsoids and polytopes are used to both graphically and numerically represent these capabilities. Ellipsoids are computationally efficient but tend to underestimate while polytopes are accurate but computationally intensive. This article proposes a new approach to RCA called the Vector Expansion (VE) method. The VE method offers accurate estimates of robot capabilities in real time and therefore is very suitable in applications like task-based decision making or online path planning. In addition, this method can provide information about the joint that is limiting a robot capability at a given time, thus giving an insight as to how to improve the performance of the robot. This method is then used to estimate capabilities of 4-DOF planar robots and the results discussed and compared with the conventional ellipsoid method. The proposed method is also successfully applied to the 7-DOF Mitsubishi PA10-7C robot

Ethyl 3-[(6-chloro­pyridin-3-yl)meth­yl]-2-oxoimidazolidine-1-carboxyl­ate

In the title compound, C12H14ClN3O3, the imidazole ring adopts a half-chair conformation. The dihedral angle between the pyridine and imidazole rings is 70.0 (1)°. In the crystal, the molecules are linked by C—H⋯O inter­actions, forming chains parallel to the c axis

An experimental investigation of the data delivery performance of a wireless sensing unit designed for structural health monitoring

This study explores the reliability of a wireless sensing unit by testing it in a real-world university laboratory environment. The unit employs off-the-shelf products for their key components, while a flexible payload scheme was adopted for radio packet transmission to maximize throughput and minimize latency. The testing consists of two main parts: (1) a series of loopback tests using two off-the-shelf radio components with carrier frequencies of 900 MHz and 2.4 GHz, respectively, and (2) wireless transmission of a shake table response to a periodic swept sine excitation. The performance of the wireless channel is examined in each part of the study. Through this experimental investigation, it is validated that a loopback test may be used as a fast prototyping approach to characterize the complex transmitting environment of a structure in which a wireless monitoring system is installed. Various factors leading to signal attenuation are ranked according to their effects on packet delivery performance. Transmitting range and building materials are among the leading factors causing packet loss (and therefore data loss) in this specific testing environment. The severity of interference from 802.11b wireless systems in close proximity to the wireless sensing unit was investigated. Some preliminary results on the influence of operating rotating machinery and human activities are to wireless sensors were investigated. The results presented herein offer a guideline for applying wireless sensing within real-world structures so that the reliability of the wireless monitoring system is maximized. Due to uncertainties associated with the reliability of wireless communications, statistical analysis is performed on the collected time histories to reveal the underlying patterns associated with data loss. Temporal correlations of data loss were measured and found to be related to the adopted radio. A statistical distribution of the size of consecutive lost data points was further derived from the collected data. Such results have identified the need to further develop: (1) reliable communication protocols to reduce these losses in data and information, and (2) robust data processing and system identification tools to anticipate and explicitly handle any data loss. Copyright © 2007 John Wiley & Sons, Ltd.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/60229/1/205_ftp.pd

1-[(6-Chloro­pyridin-3-yl)meth­yl]imidazolidin-2-iminium chloride

The title compound, C9H12ClN4 +·Cl−, is a natural metabolic product of imidacloprid [systematic name: (E)-1-(6-chloro-3-pyridyl­meth­yl)-N-nitro­imidazolidin-2-yl­idene­amine] and was obtained by the reduction of the latter using Fe in HCl. The dihedral angle between the pyridine and imidazole rings is 62.09 (12)°. The crystal structure is stabilized by N—H⋯Cl and C—H⋯Cl inter­actions involving the chloride anion. The pyridine N and the chloride atoms are not involved in inter­molecular inter­actions