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BACKGROUND Clinical variables that predict long-term mortality and recurrence of Takotsubo syndrome (TTS) are not completely understood as the role of acquired corrected QT interval (QTc) prolongation. AIM To detect the prevalence of QTc interval prolongation in patients with TTS and to evaluate its long-term prognostic impact. METHODS QTc intervals were analysed in 105 patients presenting with symptoms of TTS. These patients were included in an ongoing retrospective cohort database. The cohort was subsequently subdivided into two groups based on the presence (long QT (LQT) group, n = 73, 69.52%) or absence (non-long QT (non-LQT) group, n = 32, 30.43%) of QTc interval prolongation. Patients were followed up over a mean period of 4.2 years. The rate of life-threatening arrhythmia during the first 30 days in the LQT group was comparable with the non-LQT group (10.9 vs 12.5%), whereas in-hospital mortality and 30-day mortality occurred less frequently in the LQT group (2.7 vs 18.75%, P < 0.01). RESULTS During this time span, 17 (23.3%) patients with acquired LQT syndrome died, whereas 14 (43.7%) patients with non-LQT duration died. Kaplan-Meier survival rates were significantly higher in the LQT group than those in the non-LQT group (Log-rank-test, P = 0.02). On multivariate analysis, the QTc interval was an independent negative predictor of all-cause mortality (P = 0.02). CONCLUSION The QTc interval at admission is an independent negative predictor of long-term adverse outcome in patients with TTS.

Objectives The study sought to assess the impact of statin therapy on survival in patients presenting with ventricular tachyarrhythmias. Background Data regarding the outcome of patients with statin therapy presenting with ventricular tachyarrhythmias is limited. Methods A large retrospective registry was used including all consecutive patients presenting with ventricular tachycardia (VT) or fibrillation (VF) from 2002 to 2016. Patients with statin were compared to patients without statin therapy (non-statin). The primary prognostic endpoint was long-term all-cause death at 3 years. Uni- and multivariable Cox regression analyses were applied in propensity-score matched cohorts. Results A total of 424 matched patients was included. The rates of VT and VF were similar in both groups (VT: statin 71% vs. non-statin 68%; VF: statin 29% vs. 32%; p = 0.460). Statin therapy was associated with lower all-cause mortality at long-term follow-up (mortality rates 16% versus 33%; log rank, p = 0.001; HR = 0.438; 95% CI 0.290–0.663; p = 0.001), irrespective of the underlying type of ventricular tachyarrhythmia (VT/VF), left ventricular ejection fraction (LVEF) > 35%, presence of an activated implantable cardioverter defibrillator (ICD), cardiogenic shock or cardiopulmonary resuscitation (CPR). Conclusion Statin therapy is independently associated with lower long-term mortality in patients presenting with ventricular tachyarrhythmias on admission. Trial registration Clinicaltrials.gov, NCT02982473, 11/29/2016, Retrospectively registered.

Background Ventricular tachyarrhythmias are still associated with poor clinical outcomes. Therefore, it is important to stratify high-risk patients presenting with ventricular tachyarrhythmias for their individual risk of future outcomes. Aim To assess the impact of male sex on survival in patients presenting with ventricular tachyarrhythmias. Methods All consecutive patients surviving ventricular tachycardia (VT) and fibrillation (VF) on admission from 2002 to 2016 were included and stratified according to sex differences by propensity score matching. The primary prognostic end-point was all-cause mortality at 30 months. Secondary end-points were all-cause mortality at 30 days, at index hospitalisation, after discharge, the composite of recurrent ventricular tachyarrhythmias and appropriate implantable cardioverter defibrillator (ICD) therapies, and finally rehospitalisation related to ventricular tachyarrhythmias. Results A total of 784 (392 males and 392 females) matched patients was included. The rate of VT and VF was similar in both groups (VT: male 65% vs female 62%; VF: male 35% vs female 38%). Male sex was independently associated with the primary end-point of all-cause mortality at 30 months (31% vs 23%; hazard ratio (HR) = 1.432; 95% confidence interval (CI) 1.089-1.883; P = 0.010) as well as with the secondary end-point of all-cause mortality at index hospitalisation (mortality rate 31% vs 23%; log-rank P = 0.010; HR = 1.432; 95% CI 1.089-1.883; P = 0.010; mortality rate 10% vs 15%; HR = 1.685; 95% CI 1.117-2.542; P = 0.013). No differences in further secondary end-points were found. Sex differences of the primary end-point were predominantly observed in patients with VT at index (mortality rate 28% versus 20%; HR = 1.512; 95% CI 1.040-2.189; P = 0.028), without an ICD and with left ventricular ejection fraction ≥35% (log-rank values, P Conclusion Males presenting with ventricular tachyarrhythmias on admission were associated with higher all-cause mortality at 30 months and all-cause mortality at index hospitalisation.

A novel Generalized Dynamic Inversion (GDI) based two-loops structured control system is proposed for position and attitude control of Autonomous Underwater Vehicles (AUVs). The outer (position) loop utilizes Proportional-Derivative (PD) control of the sway and heave position error variables and provides the reference roll and pitch attitude angles to the inner loop. The inner (attitude) loop utilizes GDI control of a prescribed asymptotically stable dynamics of the attitude angles errors from their desired values, and provides the required control surface deflections such that the desired path of the vehicle is tracked. The GDI singularity avoidance is achieved by augmenting a dynamic scaling factor in the Moore-Penrose generalized inverse. The involved null control vector is constructed to be linear in the roll and pitch angular velocities, and the proportionality gain matrix is designed via a control Lyapunov function such that global closed loop stability of the internal dynamics is guaranteed. A detailed six degrees of freedom mathematical model of the Monterey Bay Aquarium Research Institute (MBARI) AUV is used to evaluate performance of the proposed control design, and numerical simulations are conducted to demonstrate its effectiveness and robustness under nominal conditions and in the presence of disturbances and parametric variations.

Atrial fibrillation is an age-dependent disease with symptomatic and prognostic implications. Treatment options include rhythm as well as rate control. However, there is a need for anticoagulation depending on calculated individual annual risk. Treatment options include antiplatelet therapy, oral anticoagulation and the use of novel oral anticoagulation (NOACs). To date, the safety and efficacy of NOACs in atrial fibrillation is established in large mega-trials. However, there is still concern on the use of NOACs in invasive procedures such as coronary angiography, electrophysiological procedures, and general surgical procedures. This review will give an overview about current data of NAOCs in procedures for rhythm control (pulmonary vein isolation and current cardioversion).

Atrial fibrillation is known to be associated with an increased risk of ischaemic stroke and systemic embolism. After stratification using various risk calculation scores, patients were traditionally prescribed anticoagulants in the form of Aspirin or the traditional Vitamin K Antagonists. The use of Warfarin has proven to reduce incidents of ischaemic stroke; however its use has several limitations. The necessity for strict anticoagulation monitoring so as to maintain the narrow therapeutic range as measured by the international normalized ratio (INR) between 2 and 3 is one of these. In clinical practice, patients are within the therapeutic range lesser than two-thirds of the time and furthermore, its use is associated with a significant risk of major bleeding. The advent of Novel oral Anticoagulants marks a new era in anticoagulant therapy. The use of direct thrombin inhibitors and Factor Xa inhibitors has documented a favorable bleeding profile while being similarly or more efficacious when compared to VKA. Early studies indicate a significant reduction in the composite of stroke or systemic embolism and lowering of all-cause mortality. In this review we discuss the evidence for the clinical benefit and safety of the novel anticoagulants versus warfarin among patients with atrial fibrillation and probationary guidelines towards their use.

Background: Recent hypotheses have suggested the pathophysiological role of catecholamines in the evolution of the Takotsubo syndrome (TTS). The extent of cardiac and circulatory compromise dictates the use of some form of supportive therapy. This study was designed to investigate the clinical outcomes associated with catecholamine use in TTS patients. Methods: Our institutional database constituted a collective of 114 patients diagnosed with TTS between 2003 and 2015. The study-patients were subsequently classified into two groups based on the need for catecholamine support during hospital stay (catecholamine group n = 93; 81%, non-catecholamine group = 21; 19%). The primary end-point of our study was all-cause mortality. Results: Patients receiving catecholamine support showed higher grades of circulatory and cardiac compromise (left ventricular ejection fraction (LVEF) 39.6% vs. 32.7%, p-value

This paper presents a generalized dynamic inversion attitude control design for satellite launch vehicle. Dynamic constraints that encapsulate the attitude tracking objectives are prescribed in the form of asymptotically stable differential equations in the attitude variables deviations from their reference trajectories. The constraint differential equations are evaluated along the vehicle's attitude trajectories and are inverted to solve for the control variables using the Greville formula for underdetermined algebraic systems. The associated null control vector is constructed using Lyapunov stability principle, and a delaying dynamic scaling factor is augmented in the involved Moore-Penrose generalized inverse for assured singularity avoidance and stable attitude tracking. The effectiveness of the proposed control scheme is shown by its evaluation on a 6DOF model of a satellite launch vehicle in the presence of various external disturbances.

Purpose Pulmonary embolism (PE) is a frequently occurring complication in critically ill patients. Simultaneous occurrence of PE and life-threatening bleeding, may render medical anticoagulation impossible. For these patients, inferior vena cava filters (IVCF) present a valuable therapeutic alternative. The Angel® catheter is a novel IVCF that provides temporary protection from PE and is implanted at bedside. The primary objective of the European Angel® catheter registry is to evaluate the safety and efficacy of this IVCF. Material and methods The European Angel® catheter registry is an observational, multi-centre registry. Patients from four countries and eight sites that have undergone Angel® catheter implantation between March 2013 and February 2017 were enrolled. Results A total of 114 critically ill patients were included. The main indication for implantation was a high-risk for PE in combination with contraindications for anticoagulation (69.3%). One clinically non-significant PE (0.9%) occurred in a patient with an indwelling Angel® catheter. No cases of catheter associated serious complications were observed. Conclusion Data shows that the Angel® catheter is a safe and effective approach to overcome the acute phase of critically ill patients with a high risk for the development of PE or an established PE, when an anticoagulation therapy is contraindicated.

Recent studies have indicated that patients with takotsubo cardiomyopathy (TTC) have a higher mortality rate than the general population. There is a distinct possibility that TTC could be associated with adverse life-threatening complications like cardiopulmonary failure. Our institutional database constituted a collective of 114 patients diagnosed with TTC. The frequency, determinants and predictors of cardiopulmonary failure were assessed. The patients were subsequently classified into two groups based on the presence (n = 44, 38.6%) or absence (n = 70, 61.4%) of cardiopulmonary failure. Multivariable logistic-regression analysis identified impaired left ventricular function defined as ≤35% at presentation and life-threatening arrhythmia as a positive significant independent predictor of cardiopulmonary failure. A majority of the patients with cardiopulmonary failure were treated with either non-invasive or invasive ventilator support (88%), while 48% of the patients required treatment with catecholamine. The in-hospital mortality rate was greater in the cardiopulmonary failure group. Cardiopulmonary failure patients were at ongoing increased risk of death with a higher mortality at 30-day, 1-year and at 5 years of follow-up. Cardiopulmonary failure is a frequent complication in TTC with an increased short- and long-term mortality. Patient susceptible to this condition could be identified by a reduced ejection fraction and life-threatening arrhythmia.

Background Iatrogenic aorto-coronary dissections following percutaneous coronary interventions (PCI) represent a rare but potentially life threatening complication. This restrospective and observational study aims to describe our in-house experience for timely diagnostics and therapy including cardiovascular imaging to follow-up securely high-risk patients with Dunning dissections. Methods Dunning dissections (DD) occurred during clinical routine PCIs, which were indicated according to current ESC guidelines. Diagnostic assessment, treatment and follow-up were based on coronary angiography with PCI or conservative treatment and cardiac computed tomography (cCTA) imaging. Results A total of eight patients with iatrogenic DD were included. Median age was 69 years (IQR 65.8–74.5). Patients revealed a coronary multi-vessel-disease in 75% with a median SYNTAX-II-score of 35.3 (IQR 30.2–41.2). The most common type of DD was type III (50%), followed by type I (38%) and type II (13%). In most patients (88%) the DD involved the right coronary arterial ostium. 63% were treated by PCI, the remaining patients were treated conservatively. 88% of patients received at least one cCTA within 2 days, 50% were additionally followed-up by cCTA within a median of 6 months (range: 4–8 months) without any residual. Conclusion Independently of the type of DD (I-III) it was demonstrated that cCTA represents a valuable imaging modality for detection and follow-up of patients with DDs.

This paper presents the robustified form of generalized dynamic inversion control and its application to attitude control for satellite launch vehicle. In proposed control law, dynamic constraint is prescribed in the form of asymptotically stable differential equation that encapsulate the control objectives. The constraint differential equation is evaluated along the vehicle's attitude trajectories and is inverted to solve for the control variables using the Moore-Penrose generalized inverse based Greville formula for under determined algebraic systems. For singularity avoidance and stable attitude tracking, a dynamic scale factor is augmented in the involved Moore-Penrose generalized inverse. An additional sliding mode control loop is augmented to make generalized dynamic inversion control robust against model uncertainties and external disturbances. The stability of the control system is ensured by using positive definite lyapunov energy function, for stable attitude tracking. An external guidance loop is applied which reshapes the reference pitch and yaw attitude profiles online based on the normal and lateral positional errors respectively, to achieve desired orbital parameters. To analyse ascent flight trajectory, a detail six degree of freedom mathematical model of four stage satellite launch vehicle is developed in Simulink/Matlab. The effectiveness of the proposed control and guidance scheme is evaluated on satellite launch vehicle simulator, in the presence of parametric variations and external disturbances.

Background Despite the extended laboratory and clinical study of sepsis, its diagnosis remains a clinical challenge. The initiation of sepsis activates many different biochemical and immunological pathways being expressed by alterations of various molecules in human tissues. The detection and measurement of the concentration of such molecules, known as biomarkers, may be a diagnostic tool of great significance for clinicians dealing with suspected sepsis. Additionally, biomarkers may predict patients ´ outcome and may play a role in monitoring response to therapy. Methods Most relevant clinical and experimental biomarker studies on sepsis were retrieved and reviewed in this article. Results Although many biomarkers were evaluated for the diagnosis and prognosis in sepsis, until now not one has been proven to be absolutely reliable in the clinical field. Currently C-reactive proteine (CPR) and procalcitonin (PCT) are used worldwide routinely, nevertheless their values may elevate in clinical settings without sepsis, while they often fail to provide reliable prediction of the patient outcome. Conclusion This review outlines most relevant circulating biomarkers in sepsis.

BACKGROUND This study evaluates the association between high sensitivity troponin I (hsTnI) and T (hsTnT) in patients with suspected stable Coronary Artery Disease (CAD) undergoing Coronary Computed Tomography Angiography (CCTA). METHODS Patients undergoing CCTA were enrolled prospectively. CCTA was indicated in patients with angina and a low to intermediate pre-test probability for CAD during routine clinical care. Blood samples were taken at the time of CCTA to measure cardiac biomarkers. RESULTS A total of 99 patients were enrolled with 43 % revealing no CAD, 30 % with non-obstructive and 26 % with obstructive CAD. Out of these, 61 % had single-vessel and 39 % had multi-vessel CAD. Both hsTnI and hsTnT levels increased significantly according to the presence and extent of CAD (p = 0.0001) and were able to discriminate the presence of both obstructive (AUC range: 0.775 - 0.785; p = 0.0001) and multi-vessel CAD (AUC range: 0.740 - 0.749; p = 0.01). In multivariate logistic regression models adjusted for cardiovascular risk factors and NT-proBNP, both hsTn were still associated significantly with obstructive CAD (range of odds ratios (OR): 8.3-32.3; p < 0.02). DISCUSSION This study shows that high sensitivity troponin I and T reflect the presence and extent of CAD being diagnosed by CCTA in patients with a low to intermediate pretest probability for CAD.

Background Acute Heart Failure (AHF), owing to the difficulties in diagnosis, prognostic stratification and patient-related management, is still associated with unusually high morbidity and mortality. The advent of novel biomarkers apart from natriuretic peptides involved in myocardial injury, neuro-hormonal activation, and ventricular remodeling augurs immense hope in redefining the biomarker-based approach towards AHF. Methods A thorough review of the available literature including latest review articles from distinguished experts, textbook references and guidelines from leading cardiological societies worldwide as well as the latest trials, encompassing various biomarkers known in AHF was conducted. The most relevant ones were chosen as references for the current review article. Results Biomarkers such as midregional proatrial natriuretic peptide, soluble ST2, highly-sensitive troponin, and midregional proadrenomedullin are some such examples that have passed various stages of substantiation while there is an array of potential biomarkers innascent stages like osteopontin, CTGF, GDF-15 and TGF beta-1 awaiting further reiteration. Not only the diagnosis of AHF itself but the evaluation of co-morbidities using markers like PCT, hematologic markers or acute kidney injury markers like NGAL present a new perspective to the management of AHF. Conclusion This review article outlines the current status of the most relevant cardiac biomarkers related to AHF.

This study aims to compare prospectively the differences of clinical outcomes being associated with a specific femoral closure (FC) compared to a radial compression (RC) device following percutaneous coronary interventions (PCI). This single-center, prospective observational study included consecutively 400 patients either treated by a specific FC (Angio-Seal™, St. Jude Medical, Inc., St. Paul, MN) or RC (TR Band®, Terumo Corporation, Tokyo, Japan) device following PCI. The primary outcome was to evaluate overall, access site and non-access site bleedings, the secondary outcome was major adverse cardiac events (MACE) occurring within 30 days of follow-up. 200 patients in each group (FC and RC group) were enrolled following PCI. The prevalence of overall bleedings was 56% in FC and 37% in RC group (p = 0.001). Access site bleedings were significantly higher in the FC (50%) compared to the RC (30%) group (p = 0.001). Most common type of access site bleeding consisted of hematomas (FC 45% vs. RC 27%, p = 0.001). Of these, intermediate and large hematomas were significantly higher in the FC group (p

Aims Previous studies revealed that patients with Takotsubo cardiomyopathy (TTC) have a higher mortality rate than the general population. Supraventricular tachycardia is a well-known complication of TTC. This study was performed to determine the short- and long-term prognostic impact of atrial fibrillation associated with TTC patients. Methods and results Our institutional database constituted a collective of 114 patients diagnosed with TTC from 2003 to 2015. The patients were divided into two groups according to the presence ( n = 21, 18.4%) or absence ( n = 93, 81.5%) of atrial fibrillation. The endpoint was a composite of in-hospital events (thromboembolic events and life-threatening arrhythmias), all-cause mortality, rehospitalization due to heart failure, stroke, and the recurrence of TTC. The in-hospital mortality, 30-day mortality, and long-term mortality were significantly higher in the atrial fibrillation group. Kaplan–Meier analysis indicated a significantly lower event-free survival rate over a mean follow-up of 3 years in the atrial fibrillation group than that in the non-atrial fibrillation group (log-rank, P < 0.01). In a multivariate cox regression analysis, atrial fibrillation (hazard ratio, HR 2.3, 95% confidence interval, CI: 1.1–4.9, P < 0.05) and EF ≤ 35% (HR 2.0, 95% CI: 1.1–3.8, P < 0.05) were the only independent predictors of a primary endpoint. Conclusion Rates of in-hospital events and short- as well as long-term mortality were significantly higher in TTC patients suffering from atrial fibrillation compared with patients without atrial fibrillation.

Background : Takotsubo cardiomyopathy (TTC) is a relevant differential diagnosis in patients presenting with signs of an acute coronary syndrome. Although recent literature has highlighted some salient features of this disorder, there has been little information elucidating the differences in clinical features, electrocardiographic findings, echocardiographic data and TTC-related complications associated with the different variants of TTC. Methods and results : Our institutional database constituted a collective of 114 patients diagnosed with TTC between 2003 and 2015 and these patients were subsequently divided into two groups based on the presence ( n = 82, 72%) or absence ( n = 32, 28%) of the apical form of TTC. The protocol for our proposed study was approved by the Ethics Committee of the University Medical Centre in Mannheim. It was noticed that the patients presenting with the apical form of TTC belonged to an older age group as compared to those presenting with the non-apical form (61.1 ± 8.9 years vs. 69.5 ± 11.2; P < 0.01). The QTc interval prolongation at index-event was observed to be quantifiably greater in the ‘apical variant’ patients group (484.8 ± 57 ms vs. 464 ± 34.1 ms; P = 0.06). With respect to cardiovascular risk factors, patients with arterial hypertension did have a higher predilection to present with the apical form (63.4% vs. 43.7%; P = 0.06), however, the impact of smoking was less pronounced in this patient group (24.4% vs. 50%, P = 0.01). Furthermore, our study highlighted a significant impact on ejection fraction (EF), with a compromised left ventricular function (36 ± 9% vs. 42.4 ± 9.7%, P < 0.01) and greater involvement of the right ventricle in the apical variant patients group (23% vs. 3%, P = 0.04). Patients with the apical form also showed a greater tendency to develop TTC-related complications such as cardiogenic shock and required longer monitoring and care in comparison. Conclusions: The apical and non-apical variants of TTC are manifestations of the same syndrome. They differ significantly, however, in their clinical presentation, related complications and prognosis.

BACKGROUND Previous studies revealed that patients with Takotsubo syndrome (TTS) have a higher mortality rate than the general population and a comparable mortality to acute coronary syndrome (ACS). Repolarisation abnormalities, namely T-wave amplitude, may provide incremental prognostic information, in addition to traditional risk factors in ACS. This study was performed to determine the short- and long-term prognostic impact of inverted T-waves in TTS patients, as compared to ACS patients. METHODS AND RESULTS Our institutional database constituted a collective of 138 patients diagnosed with TTS from 2003 to 2017, as well as 532 patients suffering from ACS. Patients with TTS or with ACS (n = 138 per group) were matched for age and sex and assessed retrospectively and prospectively and divided into two groups, TTS with inverted T-waves (n = 123) and ACS with inverted T-waves (n = 80). In-hospital complications such as respiratory failure with the need of respiratory support (60.2% vs 6.3%; P

This paper presents the design of rigid body spacecraft attitude control using robust generalised dynamic inversion (RGDI). In RGDI control, the particular part is responsible to enforce the constraint dynamics based on the attitude deviation function. The control law is extracted by inverting the prescribed constraint dynamics using Moore-Penrose generalised inverse (MPGI). The auxiliary part of the RGDI control which is affine in the null space of the control coefficient vector is utilised to stabilise the angular body rates. The singularity problem is addressed by augmenting the dynamic scale factor in MPGI. To guarantee robustness against parametric variations and disturbances, an additional term based on the concept of sliding mode control is integrated with GDI, such that semi-global practically stable attitude tracking is guaranteed. The RGDI controller's performance is evaluated through numerical simulations on the spacecraft mathematical model whose kinematical and dynamical equations are modelled in Simulink/MATLAB environment.

Background Studies have associated obesity with better outcomes in comparison to non-obese patients after elective and emergency coronary revascularization. However, these findings might have been influenced by patient selection. Therefore we thought to look into the obesity paradox in a consecutive network STEMI population. Methods The database of two German myocardial infarction network registries were combined and data from a total of 890 consecutive patients admitted and treated for acute STEMI including cardiogenic shock and cardiopulmonary resuscitation according to standardized protocols were analyzed. Patients were categorized in normal weight (≤24.9 kg/m2), overweight (25-30 kg/m2) and obese (>30 kg/m2) according to BMI. Results Baseline clinical parameters revealed a higher comorbidity index for overweight and obese patients; 1-year follow-up comparison between varying groups revealed similar rates of all-cause death (9.1 % vs. 8.3 % vs. 6.2 %; p = 0.50), major adverse cardiac and cerebrovascular [MACCE (15.1 % vs. 13.4 % vs. 10.2 %; p = 0.53)] and target vessel revascularization in survivors [TVR (7.0 % vs. 5.0 % vs. 4.0 %; p = 0.47)] with normal weight when compared to overweight or obese patients. These results persisted after risk-adjustment for heterogeneous baseline characteristics of groups. An analysis of patients suffering from cardiogenic shock showed no impact of BMI on clinical endpoints. Conclusion Our data from two network systems in Germany revealed no evidence of an “obesity paradox”in an all-comer STEMI population including patients with cardiogenic shock.

The implementation of therapeutic anticoagulation influences the severity and outcome of patients with coronary artery disease (CAD). This review aims to summarize the current guideline-based recommendations about the use of new oral anticoagulants (NOACs) in patients with stable CAD (SCAD), acute coronary syndromes (ACS), percutaneous coronary interventions (PCI) and in patients with concomitant atrial fibrillation (AF). The implications of the use of specific NOACs, such as the direct factor Xa inhibitors apixaban and rivaroxaban as well as the direct thrombin inhibitor dabigatran are outlined and compared to the benefits of vitamin k antagonists and antiplatelet agents such as thienopyridines in these settings.

This paper presents a two-loops structured control system design for quadrotor's position/attitude trajectory tracking. The aim of the outer loop is to provide the roll/pitch tilting commands to the inner loop, which in turns generates the quadrotor's tilting angles required to control the horizontal CG position. To fulfill that purpose, the outer loop utilizes Generalized Dynamic Inversion of a prescribed asymptotically stable differential equation in the errors the two horizontal position coordinates x and y from their reference trajectories. The inner loop employs Nonlinear Terminal Sliding Mode Control to control the two tilting angles ф and θ, in addition to controlling the yaw attitude angle ψ and the vertical position coordinate z. The singularity avoidance problems that are associated with Generalized Dynamic Inversion and Terminal Sliding Mode Control are addressed tactfully, and closed loop stability is guaranteed. For performance evaluation, a six degrees of freedom Quadrotor model is developed, and numerous simulations are conducted in the presence of disturbances and parametric uncertainties for analyzing the effectiveness of the proposed control system.

This paper presents a methodology based on direct adaptive fuzzy controller to control the pitch attitude of Satellite Launch Vehicle (SLV). To generate reference trajectories of a four-stage Launch Vehicle, Trajectory Optimization has been performed offline using Genetic Algorithms. The optimization routine takes into account the maximum angle of attack along with normal and lateral overload constraints. To efficiently follow the reference pitch profile, a fuzzy based controller is proposed in which an adaptation law is devised which automatically adjusts the tunable parameter. This tunable parameter is the consequent part of fuzzy IF-THEN rules. Lyapunov principle is incorporated in the adaptation law for ensuring system's stability. It is observed that although the Lyapunov approach make sure that the system is asymptotically stable, it is very critical to select appropriately the value of semi positive definite matrix. To analyze the performance of proposed control scheme, 6DOF simulation model is developed in Simulink.