No abstract

No abstract

No abstract

Induction heating or welding can be performed by considering the combined effect of ferromagnetic heating due to magnetic hysteresis losses and eddy current heating due to conductive material. Nonconducting thermoplastic composite parts can be joined or welded by induction heating using a susceptor sheet filled with nickel-coated carbon fibers (NiCCFs) and nickel-coated graphite particles (NiCGPs) or both with polypropylene (PP) thermoplastic matrix. Above the percolation threshold, NiCCFs can serve as conductive materials and nickel coating will provide the ferromagnetic heating. NiCCF/PP and NiCCF/NiCGP/PP susceptor sheets were developed via melt mixing using a twin-screw extruder and sheets were produced by Calendering process. Induction heating tests were performed on a circular pancake coil and at frequencies below 1 MHz. In induction heating, fiber heating by Joule loss, junction heating (i.e. dielectric heating and contact resistance heating), as well as magnetic hysteresis effect were observed in both the cases. Heating in hybrid filler was higher at lower filler concentrations; however, with higher concentrations, heating reduced. Reduction in induction heating maybe due to a reduction in electrical conductivity was observed. Electrical conductivity was measured in fibers direction by a Keithley electrometer using a four-point measuring method and temperature was measured by an infrared thermal camera. Microstructure characterization was performed by X-ray computed microtomography and light microscopy.

In this paper, we present a novel sensor-based system to perform defect inspection tasks automatically over free-form specular surfaces. The inspection procedure is performed by a robotic manipulator equipped with a line scanner system. Taking the geometric and optical parameters into consideration, our algorithm computes a flexible scanning path. Based on a mesh model, the system segments the convex surface into areas with similar curvatures, then adaptively adjusts the line sensor's scanning range to ensure the complete coverage of the surface. We consider the scanning efficiency through constrained optimization. To align the computed scanning path with the specular object, a real-time workpiece localization algorithm in a coarse-to-fine manner is developed. Our control framework synchronizes the motion of the manipulator and the acquisition of the line scanner for robotic inspection. We also provide an image processing pipeline for automatic defect detection. To validate the proposed formal methodology, we report a detailed experimental study with the developed robotic inspection prototype.

No abstract

In this paper, we present a new method to control the thermal stimulation of skin during a photorejuvenation procedure. The proposed method can precisely administer the thermal dose while controlling the tissue's temperature under a safe limit. For that, a model-based treatment controller is developed and evaluated on a three-dimensional biophysicsbased numerical model of skin; A hardware implementation is experimentally tested on a gelatin-based phantom tissue subjected to pulsed laser irradiation. A key component of our method is the use of a new thermal dose metric that enables quantifying and controlling the skin photo-rejuvenation process; This metric represents a suitable alternative to the lack of consensus on the metrics used by the photodermatology community. The reported experiments demonstrate that the developed controller endowed with the proposed dose unit can automatically deliver a prescribed laser irradiation and thermal dose over the tissue surface. The significance of our result is that it provides a control-theoretic framework to automate skin photorejuvenation treatments with thermal-guided robots. This approach has the potential to introduce standards in the automation of these types of photo-treatments.