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One of the expectations for the next generation of industrial robots is to work collaboratively with humans as robotic co-workers. Robotic co-workers must be able to communicate with human collaborators intelligently and seamlessly. However, industrial robots in prevalence are not good at understanding human intentions and decisions. We demonstrate a steady-state visual evoked potential (SSVEP)-based brain-computer interface (BCI) which can directly deliver human cognition to robots through a headset. The BCI is applied to a part-picking robot and sends decisions to the robot while operators visually inspecting the quality of parts. The BCI is verified through a human subject study. In the study, a camera by the side of the conveyor takes photos of each part and presents it to the operator automatically. When the operator looks at the photo, the electroencephalography (EEG) is collected through BCI. The inspection decision is extracted through SSVEPs in EEG. When a defective part is identified by the operator, the signal is communicated to the robot which locates the defective part through a second camera and removes it from the conveyor. The robot can grasp various part with our grasp planning algorithm (2FRG). We have developed a CNN-CCA model for SSVEP extraction. The model is trained on a dataset collected in our offline experiment. Our approach outperforms the existing CCA, CCA-SVM, and PSD-SVM models. The CNN-CCA is further validated in an online experiment that achieves 93% accuracy in identifying and removing a defective part.

Stroke treatment often requires analysis of vascular pathology evaluated using computed tomography (CT) angiography. Due to vascular variability and complexity, finding precise relationships between vessel geometries and arterial pathology is difficult. A new convex shape decomposition strategy was developed to understand complex vascular structures and synthesize a weighted approximate convex decomposition (WACD) method for vascular decomposition in computer-aided diagnosis.The vascular tree is decomposed into optimal number of components (determined by an expert). The decomposition is based on two primary features of vascular structures: (i) the branching factor that allows structural decomposition and (ii) the concavity over the vessel surface seen primarily at the site of an aneurysm. Such surfaces are decomposed into subcomponents. Vascular sections are reconstructed using CT angiograms. Next the dual graph is constructed, and edge weights for the graph are computed from shape indices. Graph vertices are iteratively clustered by a mesh decimation operator, while minimizing a cost function related to concavity.The method was validated by first comparing results with an approximate convex decomposition (ACD) method and next on vessel sections (n= 177) whose number of clusters (ground truth) was predetermined by an expert. In both cases, WACD produced promising results with 84.7 % of the vessel sections correctly clustered and when compared with ACD produced a more effective decomposition. Next, the algorithm was validated in a longitudinal study data of 4 subjects where volumetric and surface area comparisons were made between expert segmented sections and WACD decomposed sections that contained aneurysms. The results showed a mean error rate of 7.8 % for volumetric comparisons and 10.4 % for surface area comparisons.Decomposition of the cerebral vasculature from CT angiograms into a geometrically optimal set of convex regions may be useful for computer-assisted diagnosis. A new WACD method capable of decomposing complex vessel structures, including bifurcations and aneurysms, was developed and tested with promising results.

Abstract Cell formation (CF) consists of identifying machine groups and part families. Many CF procedures use a part machine matrix as an input and attempt to obtain a block diagonal form. But perfect block diagonalization of parts and machines is not possible is many cases. In this paper we consider a generalized cellular manufacturing (CM) problem, in which each part can have alternate process plans and each operation can be performed on alternate machines. Under these conditions the CF problem of assigning parts and machines to each manufacturing cell can be considered as a two stage process. The first stage deals with the problem of determining a unique process plan for each part. The second stage determines the part families and machine cells. In this research a model for forming part families and machine cells is presented considering alternate process plans. The objective is to analyze how alternate process plans influence and enhance the CM process giving better flexibility to the designer while designing cells for CM.

This paper presents a haptic simulator based on a force model that renders precise and crisp force feed back for a range of applications such as grinding, polishing and deburring of metals using an abrasive hand-grinding tool. Many skill based manufacturing and medical applications require a human operator to use grinding tools to impart force to remove material from a surface that may have rough texture or asperities. This paper describes the design, implementation and evaluation of this proposed system. First a force model is presented to compute forces resulting from grinding tool work piece interface. Next an image based 3D Terrain modeling algorithm is developed to simulate the details of work piece topology. To create sensation of metal removal during the grinding processes, a dynamic texture modification algorithm is developed to provide realistic virtual simulation of polishing process. Finally human subject tests are carried out to test the effectiveness of the simulator. The skill sets required for grinding operations are usually learned through practice. The grinding simulator presented here is a step towards using haptics to perfect this skill that is otherwise hard to learn quickly.

This research compared visual (color), auditory (tone pitch), and tactile (vibration amplitude) displays of uncertainty in a threat avoidance task. Thirty participants used these displays to navigate through a simulated minefield, selecting paths that would minimize their chance of hitting a mine, while moving through the field as quickly and directly as possible. Results showed the participants in the visual condition to be the most conservative (safer but longer), while those in the auditory condition took the shortest (riskier) path. Interestingly, in terms of trial time, while all participants tended to improve their performance with respect to speed, participants in the tactile condition started out more slowly, but were similar in speed to the fastest, visual condition, by the end of the trials.

We seek to characterize the features of iatrogenic spinal ischemia, determine which spinal levels are affected, and evaluate the efficacy of management strategies.

Abstract: The structural aspects of phosphate coordination in Cu(bipy)2 (H2PO4)2∼0·25 H3PO4 (1) and Cu(phen)2(H2PO4)2∼0·25 H3PO4 (2) (bipy=2,2′ bipyridyl; phen=1,10 phenanthroline) have been investigated byir, electronic andesr spectra. In both complexes bidentate coordination from H2PO 4− ion is suggested. The complexes have been assignedcis-distorted octahedral stereochemistry. It is interesting that the stereochemistry is essentially of a static nature in (1) while it is fluxional in (2).

Complexes of the type [R2Sn(OH){SSP(OR')}] (R = Et. Prn, Bun; Rt = Et, Prn, Pri) have been prepared and characterized by elemental analyses and IR and NMR spectroscopy. These complexes are associated in the solid state probably through hydroxo-bridges whereas in solution they exist in equilibrium with monomeric species.

Abstract: This paper describes an interactive system for specifying robotic tasks using virtual tools that allow an operator to reach into a live video scene and direct robots to use corresponding real tools in complex scenarios that involve integrating a variety of otherwise autonomous technologies. The attribute rich virtual tools concept provides a human-machine interface that is robust to unanticipated developments and tunable to the specific requirements of a particular task. This Interactive Specification concept is applied to intermediate manufacturing tasks.

The structural aspects of phosphate coordination in Cu(bipy)2(H2PO4)2∼0·25 H3PO4(1) and Cu(phen)2(H2PO4)2∼0·25 H3PO4(2) (bipy=2,2′ bipyridyl; phen=1,10 phenanthroline) have been investigated byir, electronic andesrspectra. In both complexes bidentate coordination from H2PO4−ion is suggested. The complexes have been assignedcis-distorted octahedral stereochemistry. It is interesting that the stereochemistry is essentially of a static nature in (1) while it is fluxional in (2).

Coordination enhancement was observed with the formation of [UO2Cl2(4-PNO)3] from DMF medium as compared to [UO2Cl2(4-PNO)3]-formed from alcohol or acetone medium. Anion addition to [UO2Cl2(L)2] and CUO2(NCS)2(L)3] (L = 2-, 3-or 4-PNO) gave [Et4N][UO2Cl3(L)] and [Et4N][UO2(NCS)3(L)2] by displacement of PNO, a hard Lewis base. Interestingly the overall energetics are favourable for these ligand displacement reactions although uranyl (VI) ion has greater affinity for hard Lewis bases.

Complexes of the type [R2Sn(OH)(SSP(OR')2] (R = Et, Prn, Bun R' = Et, Prn, Pri) have been prepared and characterized by elemental analyses and IR and NMR spectroscopy. These complexes are associated in the solid state probably through hydroxo-bridges whereas in solution they exist in equilibrium with monomeric species.

Reaction of the dialkyltin oxides (I) with the dialkyl dithiophosphates (II) produces the complexes (III) mentioned in the title.