Infrastructural Requirements and Regulatory Challenges of a Sustainable Urban Air Mobility Ecosystem

The United Nations has long put on the discussion agenda the sustainability challenges of ur- banization, which have both direct and indirect effects on future regulation strategies. Undoubtedly, most initiatives target better quality of life, improved access to services & goods and environment pro- tection. As commercial aerial urban transportation may become a feasible research goal in the near future, the connection possibilities between cities and regions scale up. It is expected that the growing number of vertical takeoff & landing vehicles used for passenger and goods transportation will change the infrastructure of the cities, and will have a significant effect on the cityscapes as well. In addition to the widely discussed regulatory and safety issues, the introduction of elevated traffic also raises environmental concerns, which influences the existing and required service and control infrastructure, and thus significantly affects sustainability. This paper provides narrated overview of the most common aspects of safety, licensing and regulations for passenger vertical takeoff & landing vehicles, and highlights the most important aspects of infrastructure planning, design and operation, which should be taken into account to maintain and efficiently operate this new way of transportation, leading to a sustainable urban air mobility ecosystem

Palládium-katalizált karbonilezési reakciók vizsgálata = Investigation of palladium carbonylation reactions

Sikeresen alkalmaztuk a palládium-katalizált karbonilezési reakciót új szteroid-aminosav hibridek, szteránvázas primer amidok, ferrocenoil-aminosavak és heterodiszubsztituált 1,1?-ferrocén-diamidok szintézisére, valamint a szteránváz és a ferrocénváz összekapcsolására. Vizsgáltuk az aminokarbonilezés és kettős karbonilezés szelektivitását befolyásoló tényezőket jód-ferrocén és aminosav-észterek, valamint aril-jodidok és aminok reakcióiban. Először valósítottunk meg kettős karbonilezést heterogenizált katalizátor segítségével átfolyásos mikroreaktorban. Homogén katalitikus és egyéb reakciók kombinálásával primer alfa-ketoamidokat, új szteránvázas imideket, N-acil-karbamid-, tetrahidro-piridazin származékokat és foszfin-oxidokat állítottunk elő. Bizonyítottuk, hogy az ionfolyadékok mint oldószerek használata lehetővé teszi a katalizátor újra felhasználását aminokarbonilezési reakcióban. Új 2beta-szubsztituált-3alfa-hidroxi- és 3alfa-szubsztituált-2beta-hidroxi-szteroidokat állítottunk elő szteránvázas epoxidok ionfolyadékok hatására lejátszódó gyűrűnyitási reakcióiban. | Palladium-catalysed carbonylation was successfully used for the synthesis of new steroid-amino acid hybrids, steroidal primary amides, ferrocenoyl amino acids, heterodisubstituted ferrocene 1,1?-diamides and ferrocene-steroid conjugates. The effect of various reaction conditions on the selectivity of aminocarbonylation and double carbonylation were investigated in the reactions of iodoferrocene with amino acid esters and in those of aryl iodides with amines. We were the first to carry out double carbonylation in a microfluidics-based flow reactor using immobilized Pd(PPh3)4 catalyst. Several primary alpha-ketoamides, new steroidal imides, steroidal N-acylurea and tetrahydro-pyridazine derivatives and phosphine oxides were synthesised by the combination of homogeneous catalytic and other organic reactions. It was proved that ionic liquids could be used as solvents in aminocarbonylation alpha- substituted -2beta-hydroxy steroids were synthesised by ionic liquid induced ring opening of steroidal epoxides

Polytopic Model Based Interaction Control for Soft Tissue Manipulation

Reliable force control is one of the key components of modern robotic teleoperation. The performance of these systems in terms of safety and stability largely depends on the controller design, as it is desired to account for various disturbing conditions, such as uncertainties of the model parameters or latency-induced problems. This work presents a polytopic qLPV model derived from a previously verified nonlinear soft tissue model, along with a model-based force control scheme that involves a tensor product polytopic state feedback controller. The derivation is based on the Tensor Product (TP) Model Transformation. The proposed force control scheme is verified and evaluated through numerical simulations. Index Terms—Soft tissue modeling, telesurgery control, Polytopic model based control, TP Model Transformation, qLPV modeling, LMI-based controller design

Nonlinear Soft Tissue Mechanics Based on Polytopic Tensor Product Modeling

Achieving reliable force control is one of the main design goals of robotic teleoperation. It is essential to grant safe and stable performance of these systems, regarding HMI control, even under major disturbing conditions such as time delay or model parameter uncertainties. This paper discusses the systematic derivation of polytopic qLPV model from the nonlinear dynamics of typical soft tissues of the human body based on recent experimental results. The derivation is based on the Tensor Product (TP) Model Transformation. The presented method is a crucial step in laying the foundations of adequate force control in telesurgery. The proposed approach could form the basis of LMI-based controller design

Reaction force and surface deformation estimation based on heuristic tissue models

In many of the advanced surgical robotic systems, soft tissue mechanics and tool–tissue interaction modeling play an important role in achieving optimal control, relying on model-based control methods. This approach allows one to address crucial issues during teleoperation, such as time-delay, stability or state observation. This paper presents a novel approach for modeling the behavior of soft tissue during surgical interventions, employing the widely-used concept of rheological models. The nonlinear Wiecher model is used for reaction force estimation during tissue indentation, tested on beef liver samples for acquiring mechanical parameters from experimental data. Curve fitting methods have been used in both stress relaxation and constant indentation speed compression phases. Reaction forces are estimated using the proposed model, followed by verification tests on ex-vivo beef liver samples. The results of this research showed that the proposed novel rheological soft tissue model is capable of estimating the reaction forces acting on the tool, if the shape of the deformed tissue is known in time

Open-Source Research Platforms and System Integration in Modern Surgical Robotics

In modern medical research and development, the variety of research tools has grown in the previous years significantly. It is crucial to exploit the benefits of shared hardware platforms and software frameworks in order to keep up with the technological development rate. Sharing knowledge in terms of algorithms, applications and instruments allows researchers to help each other’s work effectively. This is a relatively new trend in the traditionally closed domain of Computer-Integrated Surgery, where community workshops and publications are now providing a thorough overview of system design, capabilities, know-how sharing and limitations. This paper overviews the emerging collaborative platforms, focusing on available open-source research kits, software frameworks, cloud applications, teleoperation training environments and shared databases that will support the synergies of the diverse research efforts in this area

A Novel Methodology for Usability Assesment of Rheological Soft Tissue Models

The task to distinguish between soft tissues by testing their mechanical properties is often referred to as the primary cognitive role of haptic devices. It is a common view that today's surgical simulators that are using haptic interfaces should rely on simple mechanical models of soft tissues, instead of complex, parameterized finite element models, thus enhancing real-time operation and focusing on the most representative mechanical effects. This paper proposes a user-trial validation method for tissue models and their polytopic representation by creating an experimental framework for soft tissue characterization, using the da Vinci Research Kit. The characterization methdodology relies on haptic feedback from the manipulated real tissue, extending the functionality of surgical simulators using virtual tissue models created by the previously proposed soft tissue modeling method. Results showed that the tissue model represents the tissue behavior sufficiently well for use in haptic simulators, based on user experience. Furthermore, it was concluded that silicon phantoms can mimic the behavior of real tissues in various surgical scenarios, especially when using teleoperation manipulation