Automated handling and positioning of large dry carbon fibre cut-pieces with cooperating robots in rear pressure bulkhead production

For new generation long-haul aircrafts the rear pressure bulkhead is made of carbon fibre reinforced plastics. The production process is usually realised by a manually performed dry fibre preforming process followed by a vacuum assisted resin infusion. The preforming process is laborious, complex and for the workers non-ergonomic due to the handling of large cut-pieces with high positioning accuracy requirements. In order to fulfil the increasing production rates, this process has to be enhanced. For this reason the German Aerospace Centre in Augsburg develops an automated preforming process using a female tooling of the pressure bulkhead. This paper presents first investigations to handle large cut-pieces of the rear pressure bulkhead plybook by cooperating robots. The grippers used in this process are passive adjustable. They consist of five elements which are connected by ball-joints. Due to these ball-joints the geometry can be adapted to different shapes. The main objective is an investigation of suitable gripper movements in order to pick-up the cutpieces from a table by draping it, transport and place it with high lay-up accuracy in the pressure bulkhead tooling. In total four different pick-up strategies are investigated to figure out which one is suitable to handle the cut-pieces without wrinkles, folds and bridging. The best strategy is optimised and used for lay-up tests where the same requirements obtain as for the pick-up movement. In conclusion the used gripper system can ensure a material handling without damage. Consequently it is possible to realise the preforming process with the passive and less complex gripper system. This may result in a more reliable and cost-effective process

Molekulare Signalwege der aseptischen Endoprothesenlockerung

Die Behandlung von immobilisierenden degenerativen und entzündlichen Gelenkerkrankungen mit der Implantation von Endoprothesen ist ein großer Erfolg und Fortschritt in der Medizin und hat stark zur Verbesserung der Lebensqualität der betroffenen Patienten beigetragen. Jährlich werden weltweit ca. 1,3 Mio. Endoprothesen implantiert, davon allein 500.000 in den USA. Dennoch sind die einmal implantierten Prothesen nicht von lebenslanger Dauer und unterliegen multiplen Einflüssen. Trotz immer neuer Entwicklungen müssen innerhalb der ersten 15 Jahre bis zu 10% der Implantate aufgrund vorzeitiger Prothesenlockerung gewechselt werden. Bei vorzeitiger Lockerung ohne Infekt oder Trauma spricht man von aseptischer Lockerung. Es ist allgemein bekannt, dass durch Abrieb entstandene Kleinstpartikel und aktivierte Makrophagen die Hauptrolle im Prozess der aseptischen Lockerung spielen. Die Pathophysiologie ist jedoch noch nicht vollständig erklärt. Die vorliegende Arbeit gibt eine Übersicht über die anerkannten molekularen Mechanismen und die Signalwege, die zur aseptischen Prothesenlockerung führen. Außerdem werden neue Therapieoptionen zur Vermeidung der aseptischen Lockerung diskutier

Safety and efficacy outcomes of double vs. triple antithrombotic therapy in patients with atrial fibrillation following percutaneous coronary intervention: a systematic review and meta-analysis of non-vitamin K antagonist oral anticoagulant-based randomized clinical trials.

Abstract Aims To investigate the safety and efficacy of double vs. triple antithrombotic therapy (DAT vs. TAT) in patients with atrial fibrillation (AF) and acute coronary syndrome or who underwent percutaneous coronary intervention (PCI). Methods and results A systematic review and meta-analysis was performed using PubMed to search for non-vitamin K antagonist oral anticoagulant (NOAC)-based randomized clinical trials comparing DAT vs. TAT in AF patients undergoing PCI. Four trials encompassing 10 234 patients (DAT = 5496 vs. TAT = 4738) were included. The primary safety endpoint (ISTH major or clinically relevant non-major bleeding) was significantly lower with DAT compared with TAT [risk ratio (RR) 0.66, 95% confidence interval (CI) 0.56–0.78; P < 0.0001; I2 = 69%], which was consistent across all available bleeding definitions. This benefit was counterbalanced by a significant increase of stent thrombosis (RR 1.59, 95% CI 1.01–2.50; P = 0.04; I2 = 0%) and a trend towards higher risk of myocardial infarction with DAT. There were no significant differences in all-cause and cardiovascular death, stroke and major adverse cardiovascular events. The comparison of NOAC-based DAT vs. vitamin K antagonist (VKA)-TAT yielded consistent results and a significant reduction of intracranial haemorrhage (RR 0.33, 95% CI 0.17–0.65; P = 0.001; I2 = 0%). Conclusion Double antithrombotic therapy, particularly if consisting of a NOAC instead of VKA and a P2Y12 inhibitor, is associated with a reduction of bleeding, including major and intracranial haemorrhages. This benefit is however counterbalanced by a higher risk of cardiac—mainly stent-related—but not cerebrovascular ischaemic occurrences

Simulation based draping of dry carbon fibre textiles with cooperating robots

Carbon fibre-reinforced plastic (CFRP) is a promising material for aircraft and other lightweight applications. To be competitive with low-cost metal based solutions highly effective and flexible production technologies are required. For this purpose production systems comprising automated fibre placement or automated tape laying technology are on the market for several years and widely spread. However, there is still a lack of automated systems capable of producing preforms efficiently and flexibly from textile semi-finished goods. Non-crimp fabrics (NCF) and weaves have to undergo considerable shear and reshaping during the layup of 3D-curved preforms in order to properly fit the 2D cut pieces to the moulds. At the Center for Lightweight Production Technology (ZLP) a digital and automated process for the easy draping of large NCF and weave cut pieces with several robots according to the previous draping simulation has been set up and tested in a robotic work cell. The details of converting the draping simulation into correct and easy to setup motions for cooperating robots and how to execute the entire process autonomously, i.e. without teaching the robots, are described. On the basis of preliminary tests the system’s capabilities on a large scale demonstrator part resembling an airplane’s rear pressure bulkhead are evaluated. An overview of the system’s architecture from simulation based planning to detecting, correct gripping, collision free autonomous transport and laydown of the cut pieces is also given

Intraoperative Defibrillation Testing of Subcutaneous Implantable Cardioverter‐Defibrillator Systems—A Simple Issue?

Background: The results of the recently published randomized SIMPLE trial question the role of routine intraoperative defibrillation testing. However, testing is still recommended during implantation of the entirely subcutaneous implantable cardioverter‐defibrillator (S‐ICD) system. To address the question of whether defibrillation testing in S‐ICD systems is still necessary, we analyzed the data of a large, standard‐of‐care prospective single‐center S‐ICD registry. // Methods and Results: In the present study, 102 consecutive patients received an S‐ICD for primary (n=50) or secondary prevention (n=52). Defibrillation testing was performed in all except 4 patients. In 74 (75%; 95% CI 0.66–0.83) of 98 patients, ventricular fibrillation was effectively terminated by the first programmed internal shock. In 24 (25%; 95% CI 0.22–0.44) of 98 patients, the first internal shock was ineffective and further internal or external shock deliveries were required. In these patients, programming to reversed shock polarity (n=14) or repositioning of the sensing lead (n=1) or the pulse generator (n=5) led to successful defibrillation. In 4 patients, a safety margin of <10 J was not attained. Nevertheless, in these 4 patients, ventricular arrhythmias were effectively terminated with an internal 80‐J shock. // Conclusions: Although it has been shown that defibrillation testing is not necessary in transvenous ICD systems, it seems particular important for S‐ICD systems, because in nearly 25% of the cases the primary intraoperative test was not successful. In most cases, a successful defibrillation could be achieved by changing shock polarity or by optimizing the shock vector caused by the pulse generator or lead repositioning.<br

Autonomous Composite Production by Robotic Pick & Place

During the last decade the DLR Center of Lightweigth Production Technology (ZLP) in Augsburg investigated the potential of the autonomous production of composite parts by means of pick and place executed by industrial robots. Starting from conventional teaching the research focus was extended to the development of technology bricks for computer vision based gripping, automated derivation of grip- and drop coordinates from CAD data, digital process description and workflow, autonomous cut-piece transfer by means of collision free path planning and a multi-robot synchronization and execution layer. The technology bricks are enriched by a process data acquisition system and controlled by a manufacturing execution system embedded into a high-level process control system. In this work we give an overview of the developed technologies and achievements based upon several use cases from the field of composite production

Divergent electrophysiologic action of dapagliflozin and empagliflozin on ventricular and atrial tachyarrhythmias in isolated rabbit hearts

BackgroundThe use of SGLT-2 inhibitors has revolutionized heart failure therapy. Evidence suggests a reduced incidence of ventricular and atrial arrhythmias in patients with dapagliflozin or empagliflozin treatment. It is unclear to what extent the reduced arrhythmia burden is due to direct effects of the SGLT2 inhibitors or is solely a marker of improved cardiac function.MethodsOne hundred five rabbit hearts were allocated to eight groups and retrogradely perfused, employing a Langendorff setup. Action potential duration at 90% of repolarization (APD90), QT intervals, effective refractory periods, conduction velocity, and dispersion of repolarization were obtained with monophasic action potential catheters. A model for tachyarrhythmias was established with the IKr blocker erythromycin for QT prolongation associated proarrhythmia as well as the potassium channel opener pinacidil for a short-QT model. An atrial fibrillation (AF) model was created with isoproterenol and acetylcholine. With increasing concentrations of both SGLT2 inhibitors, reductions in QT intervals and APD90 were observed, accompanied by a slight increase in ventricular arrhythmia episodes. During drug-induced proarrhythmia, empagliflozin succeeded in decreasing QT intervals, APD90, and VT burden whereas dapagliflozin demonstrated no significant effects. In the presence of pinacidil induced arrhythmogenicity, neither SGLT2 inhibitor had a significant impact on cardiac electrophysiology. In the AF setting, perfusion with dapagliflozin showed significant suppression of AF in the course of restitution of electrophysiological parameters whereas empagliflozin showed no significant effect on atrial fibrillation incidence.ConclusionIn this model, empagliflozin and dapagliflozin demonstrated opposite antiarrhythmic properties. Empagliflozin reduced ventricular tachyarrhythmias whereas dapagliflozin showed effective suppression of atrial arrhythmias

Subcutaneous implantable cardioverter-defibrillators: long-term results of the EFFORTLESS study

AIMS: To report 5-year outcomes of EFFORTLESS registry patients with early generation subcutaneous implantable cardioverter-defibrillator (S-ICD) devices. METHODS AND RESULTS: Kaplan-Meier, trend and multivariable analyses were performed for mortality and late (years 2-5) complications, appropriate shock (AS) and inappropriate shock (IAS) rates. Nine hundred and eighty-four of 994 enrolled patients with diverse diagnoses (28% female, 48 ± 17 years, body mass index 27 ± 6 kg/m2, ejection fraction 43 ± 18%) underwent S-ICD implantation. Median follow-up was 5.1 years (interquartile range 4.7-5.5 years). All-cause mortality was 9.3% (95% confidence interval 7.2-11.3%) at 5 years; 703 patients remained in follow-up on study completion, 171 withdrew including 87 (8.8%) with device explanted, and 65 (6.6%) lost to follow-up. Of the explants, only 20 (2.0%) patients needed a transvenous device for pacing indications. First and final shock efficacy for discrete ventricular arrhythmias was consistent at 90% and 98%, respectively, with storm episode final shock efficacy at 95.2%. Time to therapy remained unaltered. Overall 1- and 5-year complication rates were 8.9% and 15.2%, respectively. Early complications did not predict later complications. There were no structural lead failures. Inappropriate shock rates at 1 and 5 years were 8.7% and 16.9%, respectively. Self-terminating inappropriately sensed episodes predicted late IAS. Predictors of late AS included self-terminating appropriately sensed episodes and earlier AS. CONCLUSION: In this diverse S-ICD registry population, spontaneous shock efficacy was consistently high over 5 years. Very few patients underwent S-ICD replacement with a transvenous device for pacing indications. Treated and self-terminating arrhythmic episodes predict future shock events, which should encourage more personalized device optimization. KEY QUESTION: Is subcutaneous implantable cardioverter-defibrillator (S-ICD) shock efficacy maintained over time? KEY FINDING: Subcutaneous implantable cardioverter-defibrillator shock efficacy remains high for discrete and storm episodes. For discrete episodes first and final shock efficacy do not change over time or by rhythm type. TAKE-HOME MESSAGE: The EFFORTLESS study 5-year results provide the longest follow up of a large patient cohort implanted with the S-ICD. For 984 patients with a median follow-up of 5.1 years, the S-ICD maintains a high level of shock efficacy of 98%