Comparison of localization methods for a robot soccer team

Abstract: In this work, several localization algorithms that are designed and implemented for Cerberus'05 Robot Soccer Team are analyzed and compared. These algorithms are used for global localization of autonomous mobile agents in the robotic soccer domain, to overcome the uncertainty in the sensors, environment and the motion model. The algorithms are Reverse Monte Carlo Localization (R-MCL), Simple Localization (S-Loc) and Sensor Resetting Localization (SRL). R-MCL is a hybrid method based on both Markov Localization (ML) and Monte Carlo Localization (MCL) where the ML module finds the region where the robot should be and MCL predicts the geometrical location with high precision by selecting samples in this region. S-Loc is another localization method where just one sample per percept is drawn, for global localization. Within this method another novel method My Environment (ME) is designed to hold the history and overcome the lack of information due to the drastically decrease in the number of samples in S-Loc. ME together with S-Loc is used in the Technical Challenges in Robocup 2005 and play an important role in ranking the First Place in the Challenges. In this work, these methods together with SRL, which is a widely used successful localization algorithm, are tested with both offline and real-time tests. First they are tested on a challenging data set that is used by many researches and compared in terms of error rate against different levels of noise, and sparsity. Besides time required recovering from kidnapping and speed of the methods are tested and compared. Then their performances are tested with real-time tests with scenarios like the ones in the Technical Challenges in ROBOCUP. The main aim is to find the best method which is very robust and fast and requires less computational power and memory compared to similar approaches and is accurate enough for high level decision making which is vital for robot soccer

Boyd Amputation in Adults

Background:Foot ulcerations resulting in amputation are one of the most devastating consequences of diabetes mellitus and peripheral arterial disease. In foot amputations, Boyd amputation has been even less accepted than Syme amputation due to its dependence on calcaneotibial osseous union in adults.Methods:Fifteen Boyd amputations were performed for 14 adults. The indications for amputation were diabetic ulceration of the foot in eight patients, ischemic disease of the lower extremity in four and salvage of the deformed foot due to peripheral neuropathy in one patient. One patient with scleroderma had bilateral amputations due to digital ischemic necrosis.Results:Complete wound healing was documented in seven feet of six patients. Further revisions to a more proximal amputation level were required in seven patients.Conclusion:Despite the high failure rate, we believe Boyd amputation is still a good option in some patients to try to preserve length. Level of Evidence: IV, Retrospective Case Series</jats:sec

The relation between elbow range of motion and patient satisfaction after open release of stiff elbow

Objective: The aim of this retrospective study was to find out whether a cut off value existed for elbow flexion and extension after open surgical release of elbow contracture that would correlate with subjective patient satisfaction. Methods: The study enrolled 77 patients (53 males and 24 females with a mean age of 35.1 (18–77) years at the time of operation) with elbow contracture who attended regular follow-up appointments for more than 12 months. The mean follow up period was 44.2 months (12–186). The preoperative and postoperative modified MAYO elbow scores, objective parameters of increase in both flexion and extension end point measurements and improvement in total ROM were compared in order to determine the cut off degree of ROM in both flexion and extension that significantly correlated with patient satisfaction. Results: Of the 77 participating patients, 26 patients had an extrinsic (33.8%) and 51 patients had an intrinsic elbow contracture (66.2%). Surgeries performed involved 40 cases of lateral release and 37 cases of both lateral and medial (progressive) release. The median preoperative total flexion-extension arch (ROM) was 45° (20°–65°). The median postoperative total flexion-extension arch (ROM) was 110° (97.5°–125°). The modified MAYO elbow score improved from 60 to 85 points postoperatively. The postoperative flexion cut off value was 115° for an excellent or good postoperative modified MAYO elbow score. Conclusion: Post-operative flexion cut off value was 115° and had a positive effect on the postoperative patient satisfaction. The cut off value for postoperative extension was 20° but it was not a significant variable on patient satisfaction as was the total increase in ROM. Level of significance: Level IV Therapeutic Study. Keywords: Contracture release, Elbow contracture, Elbow flexio