2,711 research outputs found
Recommended from our members
Mobile Paving System (MPS): A New Large Scale Freeform Fabrication Method
In the last decade, significant opportunities for automation have been identified in the area of
construction. Soaring labor and material costs have driven multiple research efforts in
construction automation. In this paper, we present a novel means for construction automation
that involves the fusion of the rapid prototyping, controls and mechatronics technologies. The
resultant autonomous construction mechanism has been designed for commercial applications.
Mobile Paving System (MPS) is a new freeform fabrication process which is capable of rapidly
producing variable profiles such as curbs and sidewalks out of materials like cement and asphalt.
Path generation and guidance of the construction operation is controlled by a mobile robot. This
article presents an overview of research and development efforts that are aimed at establishing
the feasibility and the potential of the process.Mechanical Engineerin
PSO-Based Optimal Coverage Path Planning for Surface Defect Inspection of 3C Components with a Robotic Line Scanner
The automatic inspection of surface defects is an important task for quality
control in the computers, communications, and consumer electronics (3C)
industry. Conventional devices for defect inspection (viz. line-scan sensors)
have a limited field of view, thus, a robot-aided defect inspection system
needs to scan the object from multiple viewpoints. Optimally selecting the
robot's viewpoints and planning a path is regarded as coverage path planning
(CPP), a problem that enables inspecting the object's complete surface while
reducing the scanning time and avoiding misdetection of defects. However, the
development of CPP strategies for robotic line scanners has not been
sufficiently studied by researchers. To fill this gap in the literature, in
this paper, we present a new approach for robotic line scanners to detect
surface defects of 3C free-form objects automatically. Our proposed solution
consists of generating a local path by a new hybrid region segmentation method
and an adaptive planning algorithm to ensure the coverage of the complete
object surface. An optimization method for the global path sequence is
developed to maximize the scanning efficiency. To verify our proposed
methodology, we conduct detailed simulation-based and experimental studies on
various free-form workpieces, and compare its performance with a
state-of-the-art solution. The reported results demonstrate the feasibility and
effectiveness of our approach
Modeling of Complex Parts for Industrial WaterJet Cleaning
Industrial high-pressure waterjet cleaning is common to many industries. The modeling in this paper functions inside a collaborative robotic framework for high mix, low volume processes where human robot collaboration is beneficial. Automation of pressure washing is desirable for economic and ergonomic reasons. An automated cleaning system needs path simulation and analysis to give the operator insight into the predicted cleaning performance of the system. In this paper, ablation, the removal of a substrate coating by waterjet, is modeled for robotic cleaning operations. The model is designed to work with complex parts often found in spray cleaning operations, namely parts containing hidden portions, holes, or concavities. Experimentation is used to validate and calibrate the ablation model to yield accurate evaluations for how well every feature of a part is cleaned based on the cumulative effect of water affecting the part surface. The ablation model will provide the foundation for optimizing process parameters for robotic waterjet cleaning
Optimisation of surface coverage paths used by a non-contact robot painting system
This thesis proposes an efficient path planning technique for a non-contact optical
“painting” system that produces surface images by moving a robot mounted laser across
objects covered in photographic emulsion. In comparison to traditional 3D planning
approaches (e.g. laminar slicing) the proposed algorithm dramatically reduces the overall
path length by optimizing (i.e. minimizing) the amounts of movement between robot
configurations required to position and orientate the laser.
To do this the pixels of the image (i.e. points on the surface of the object) are sequenced
using configuration space rather than Cartesian space. This technique extracts data from a
CAD model and then calculates the configuration that the five degrees of freedom system
needs to assume to expose individual pixels on the surface. The system then uses a closest
point analysis on all the major joints to sequence the points and create an efficient path
plan for the component.
The implementation and testing of the algorithm demonstrates that sequencing points using
a configuration based method tends to produce significantly shorter paths than other
approaches to the sequencing problem. The path planner was tested with components
ranging from simple to complex and the paths generated demonstrated both the versatility
and feasibility of the approach
Virtual Structure Based Formation Tracking of Multiple Wheeled Mobile Robots: An Optimization Perspective
Today, with the increasing development of science and technology, many systems need to be optimized to find the optimal solution of the system. this kind of problem is also called optimization problem. Especially in the formation problem of multi-wheeled mobile robots, the optimization algorithm can help us to find the optimal solution of the formation problem. In this paper, the formation problem of multi-wheeled mobile robots is studied from the point of view of optimization. In order to reduce the complexity of the formation problem, we first put the robots with the same requirements into a group. Then, by using the virtual structure method, the formation problem is reduced to a virtual WMR trajectory tracking problem with placeholders, which describes the expected position of each WMR formation. By using placeholders, you can get the desired track for each WMR. In addition, in order to avoid the collision between multiple WMR in the group, we add an attraction to the trajectory tracking method. Because MWMR in the same team have different attractions, collisions can be easily avoided. Through simulation analysis, it is proved that the optimization model is reasonable and correct. In the last part, the limitations of this model and corresponding suggestions are given
The infrared imaging spectrograph (IRIS) for TMT: on-instrument wavefront sensors and NFIRAOS interface
The InfraRed Imaging Spectrograph (IRIS) is a first light client science
instrument for the TMT observatory that operates as a client of the NFIRAOS
facility multi-conjugate adaptive optics system. This paper reports on the
concept study and baseline concept design of the On-Instrument WaveFront
Sensors (OIWFS) and NFIRAOS interface subsystems of the IRIS science
instrument, a collaborative effort by NRC-HIA, Caltech, and TMT AO and
Instrument teams. This includes work on system engineering, structural and
thermal design, sky coverage modeling, patrol geometry, probe optics and
mechanics design, camera design, and controls design.Comment: 17 pages, 12 figures, SPIE7735-28
Integrated process planning for a hybrid manufacturing system
A hybrid manufacturing system integrated CNC machining and laser-aided layered deposition and achieves the benefits of both processes. In this dissertation, an integrated process planning framework which aims to automate the hybrid manufacturing process is investigated. Critical components of the process planning, including 3D spatial decomposition of the CAD model, improvement of the toolpath generation pattern, repairing strategies using a hybrid manufacturing system, etc., are discussed --Abstract, page iv
- …