Improved vision based pose estimation for industrial robots via sparse regression

In this work amonocular machine vision based pose estimation system is developed for industrial robots and the accuracy of the estimated pose is im-proved via sparse regression. The proposed sparse regressionbased methodis usedimprove the accuracy obtained from the Levenberg-Marquardt (LM) based pose estimation algorithmduring the trajectory tracking of an industrial robot’s end effector. The proposed method utilizes a set of basis functions to sparsely identify the nonlinear relationship between the estimated pose and the true pose provided by a laser tracker.Moreover,a camera target was designed and fitted with fiducial markers,andto prevent ambiguities in pose estimation, the markers are placed in such a way to guarantee the detection of at least two distinct nonparallel markers from a single camera within ± 90° in all directions of the cam-era’s view. The effectiveness of the proposed method is validated by an experi-mental study performed using a KUKA KR240 R2900 ultra robot while follow-ing sixteen distinct trajectories based on ISO 9238. The obtained results show that the proposed method provides parsimonious models which improve the pose estimation accuracy and precision of the vision based system during trajectory tracking of industrial robots' end effector

Dental arch relationships in turkish patients with complete unilateral cleft lip and palate born between 1976 and 1990: A comparison with eurocleft

PubMedID: 22849640Objective: To compare the dental arch relationships of Turkish patients with complete unilateral cleft lip and palate (UCLP) with the results reported for participants in the Eurocleft study. Patients: Study models of 109 patients with complete UCLP from five university clinics in Turkey were evaluated (clinic A=25 patients, clinic B=23 patients, clinic C=20 patients, clinic D = 21 patients, and clinic E = 20 patients). The mean age of the patient cohort was nine years old (range = 8-11 years old), and the cohort was born between 1976 and 1990. Methods: The examiners rated the three-dimensional (3D) models using the GOSLON Yardstick. The scores were compared with those from the Eurocleft centers: E1(B), E2(E), E3(A), E4(F), E5(C), and E6(D). Intra- and interexaminer agreements were evaluated using weighted kappa statistics. Results: The mean GOSLON scores for the Turkish clinics were as follows: clinic A = 3.16, clinic B = 3.13, clinic C = 3.25, clinic D =3.67, and clinic E = 3.70. Scores for three of the Turkish clinics (A, B, and C) were significantly worse than the scores for the three best Eurocleft centers, E1(B), E2(E), and E3(A) (P , .001, P , .001, and P , .05, respectively). Scores for two of the Turkish clinics (D and E) were similar to those for Eurocleft center E6(D) but worse than the scores for the other Eurocleft centers (P , .01, P , .001, respectively). Conclusions: This was the first study in which three-dimensional models were used to derive scores to compare with those of the Eurocleft centers. According to the results of analysis of 109 3D models, 50.4 % of the patients in Turkey were classified as GOSLON score 4 and 5. This may have been attributable to poor surgical procedures, low-volume surgeons, and the decentralized treatment approach in Turkey between 1985 and 2000. Further research is needed to assess the situation in Turkey in more recent years. © Copyright 2014 American Cleft Palate-Craniofacial Association

Grundlagen zum Umformen lackierter Bleche ohne Schmierstoff Abschlussbericht

SIGLEAvailable from TIB Hannover: F00B757+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung und Forschung (BMBF), Bonn (Germany)DEGerman

Biomedical device prototype based on small scale hydrodynamic cavitation

This study presents a biomedical device prototype based on small scale hydrodynamic cavitation. The application of small scale hydrodynamic cavitation and its integration to a biomedical device prototype is offered as an important alternative to other techniques, such as ultrasound therapy, and thus constitutes a local, cheap, and energy-efficient solution, for urinary stone therapy and abnormal tissue ablation (e.g., benign prostate hyperplasia (BPH)). The destructive nature of bubbly, cavitating, flows was exploited, and the potential of the prototype was assessed and characterized. Bubbles generated in a small flow restrictive element (micro-orifice) based on hydrodynamic cavitation were utilized for this purpose. The small bubbly, cavitating, flow generator (micro-orifice) was fitted to a small flexible probe, which was actuated with a micromanipulator using fine control. This probe also houses an imaging device for visualization so that the emerging cavitating flow could be locally targeted to the desired spot. In this study, the feasibility of this alternative treatment method and its integration to a device prototype were successfully accomplished