Insertion Maneuver Research Articles

Tisserand-Leveraging Lambert Problem: Formulation, Solution, and Applications

Tisserand-leveraging transfers (TILTs) were proposed as techniques to achieve an endgame tour with small orbit insertion maneuvers and short flight times in low-energy regions of the planar, circular, restricted three-body problem. This paper presents a new formulation of TILTs with a framework similar to the classical Lambert problem. The developed algorithm searches for trajectories of TILTs with constraints on boundary values and time of flight by solving a one-dimensional root-finding problem. Compared to the traditional algorithm for TILTs, the developed algorithm enhances its generality by removing the restriction on the initial and final phases of the transfer. Additionally, the algorithm can achieve trajectory patching that includes TILTs without reoptimization and tour redesign based on the actual position of the spacecraft due to the Lambert-like input–output design. The algorithm uses existing neural network tools for fast and broad search in the solution space. Simulation results indicate that the algorithm can explicitly find TILT solutions and families satisfying boundary value constraints. Furthermore, the algorithm is applied to design a new endgame trajectory from Ganymede to Europa, demonstrating the potential of integrating the new algorithms with other trajectory design tools.

Korea Pathfinder Lunar Orbiter (KPLO) Operation: From Design to Initial Results

Korea Pathfinder Lunar Orbiter (KPLO) is South Korea’s first space exploration mission, developed by the Korea Aerospace Research Institute. It aims to develop technologies for lunar exploration, explore lunar science, and test new technologies. KPLO was launched on August 5, 2022, by a Falcon-9 launch vehicle from cape canaveral space force station (CCSFS) in the United States and placed on a ballistic lunar transfer (BLT) trajectory. A total of four trajectory correction maneuvers were performed during the approximately 4.5-month trans-lunar cruise phase to reach the Moon. Starting with the first lunar orbit insertion (LOI) maneuver on December 16, the spacecraft performed a total of three maneuvers before arriving at the lunar mission orbit, at an altitude of 100 kilometers, on December 27, 2022. After entering lunar orbit, the commissioning phase validated the operation of the mission mode, in which the payload is oriented toward the center of the Moon. After completing about one month of commissioning, normal mission operations began, and each payload successfully performed its planned mission. All of the spacecraft operations that KPLO performs from launch to normal operations were designed through the system operations design process. This includes operations that are automatically initiated post-separation from the launch vehicle, as well as those in lunar transfer orbit and lunar mission orbit. Key operational procedures such as the spacecraft’s initial checkout, trajectory correction maneuvers, LOI, and commissioning were developed during the early operation preparation phase. These procedures were executed effectively during both the early and normal operation phases. The successful execution of these operations confirms the robust verification of the system operation.

Lunar Orbit acquisition of the Korea Pathfinder lunar orbiter: Design reference vs actual flight results

The Korea Pathfinder Lunar Orbiter (KPLO), officially named as Danuri, is the Republic of Korea's first spacecraft to orbit the Moon. The goal of KPLO is to secure core deep space technology for future space exploration in Korea and contribute to lunar science by gathering data from the lunar orbit for one year. This paper presents the results of KPLO's Lunar Orbit Acquisition (LOA) phase in detail, with a particular focus on the operational results of Flight Dynamics (FD). During the LOA phase, the KPLO FD team experienced many expected and unexpected issues. These issues were mitigated by making real-time updates to the LOA phase Design Reference Mission (DRM). The paper also presents the results of the Orbit Determination (OD) and performance of each Lunar Orbit Insertion (LOI) maneuver conducted during the actual flight operation. The importance of considering operational constraints when designing the DRM is emphasized by presenting lessons learned based on actual flight experiences. Unlike the original KPLO LOA phase DRM, KPLO successfully achieved the final mission orbit using only three LOI burns, instead of the planned five LOI burns and an Orbit Trim Maneuver (OTM). Despite the extensive revisions made to the DRM, all mission requirements were still fulfilled during the final lunar orbit insertion, taking into account the significant operational constraints.

Impacts of bus overtaking policies on the capacity of bus stops

Long bus queues at busy stops plague bus systems in many cities. Since berths are laid-out in tandem, buses’ overtaking maneuvers are often prohibited or restricted, which can significantly reduce a bus stop’s discharge capacity. When overtaking is allowed, aggressive drivers may perform disruptive oblique insertion maneuvers that would undermine stop capacity and compromise safety. This paper develops parsimonious yet realistic simulation models to examine the impacts of different overtaking policies on bus-stop capacity. Key realistic features are considered, including the oblique insertions resulting from overtaking, impacts of a nearby traffic signal, and bus traffic characteristics (reaction and move-up times). Extensive numerical experiments unveil many new findings. Some are at odds with those reported by previous studies. In addition, we examine two strategies that can improve the stop capacity without incurring disruptive oblique insertions. Practical implications of our findings are discussed, especially on choosing the most productive overtaking policy and means to minimize the capacity lost to buses’ mutual blockage at stops. These implications have broad applications to various types of bus stops.

Design of an in-situ science mission to a Jupiter Trojan

The NASA mission Lucy, launched in 2021, will perform flybys at several Jupiter Trojan asteroids. The logical next step is a close orbiter and/or lander for in situ science at specific Trojans. The present paper reports results for a feasible design of such a mission to the largest Jupiter Trojan, 624 Hektor. The suggested principle, which involves a powered Jupiter gravity assist followed by an extended drift arc towards the target body and an insertion maneuver of around 1 ​km/s, has been found to lead to comparable mission options for a number of other target Trojans.

To compare the influence of blind insertion and up-down optimized glottic exposure manoeuvre on oropharyngeal leak pressure using SaCoVLM™ video laryngeal mask among patients undergoing general anesthesia

To compare the potential influences of blind insertion and up-down optimized glottic exposure manoeuvre on the oropharyngeal leak pressure (OPLP) in using SaCoVLM™ video laryngeal mask (VLM) among patients undergoing general anesthesia. A randomized self-control study controlled was conducted to investigate the effect of two insertion techniques on OPLP. A total of 60 patients (male or female, 18–78 years, BMI 18.0–30.0 kg m−2 and ASA I–II) receiving selective surgery under general anesthesia were randomly recruited. After induction of anesthesia, the SaCoVLM™ was inserted by blind insertion manoeuvre. The glottic exposure grading(V1) of the SaCoVLM™ visual laryngeal mask and the OPLP(P1) were recorded. And the glottic exposure grading(V2) and OPLP(P2) of SaCoVLM™ were recorded again when the glottic exposure grading was optimal. The glottis exposure grading and OPLP were compared before and after different insertion manoeuver. The glottic exposure grading (V2) obtained by using up-down optimized glottic exposure manoeuvre was better than that obtained by using blind insertion manoeuvre (V1)(P < 0.001). The OPLP was significantly lower in the blind insertion manoeuvre (P1) than in the up-down optimized glottic exposure manoeuvre (P2) (32.4 ± 5.0 cmH2O vs. 36.3 ± 5.2 cmH2O, P < 0.001). In using SaCoVLM™, higher OPLP and better glottic exposure grading were achieved through up-down optimized glottic exposure manoeuvre, protecting the airway while real-time monitoring of conditions around the glottis, which significantly improves airway safety. Our results suggests that up-down optimized glottic exposure manoeuver may be a useful technique for SaCoVLM™ insertion.Trial registration: ChiCTR, ChiCTR2000028802. Registered 4 January 2020, http://www.chictr.org.cn/ChiCTR2000028802.

A refashioned foley catheter: novel cost-effective available stent in pediatric laryngotracheal reconstruction

PurposePediatric laryngotracheal reconstruction (LTR) for laryngotracheal stenosis (LTS) mandates stenting in certain situations. This study presents a novel commercially available and cost-effective stent, a refashioned foley catheter.MethodsThis prospective clinical study was performed on pediatric cases with LTS up to 8 years. The study was performed in a tertiary referral center. The selection of the proper foley catheter size for age was explained. The atraumatic insertion maneuver of the stent was also shown in detail in different situations of LTS. The endoscopic removal of the stent was also described. The mean follow-up was 6.45 ± 1.3 months.ResultsThe study included 31 cases using the refashioned foley catheter stents. The study included 17 males and 14 females with a mean age of 3.45 ± 1.09. Subglottic stenosis was the most common cause of LTR in the study (74.2%) cases. The mean duration of stenting was 40.5 ± 3.7 days. Decannulation was achieved in 96.8% of cases. No stent complications were encountered like stent migration, excess granulation tissue, intractable aspiration, or pressure necrosis.ConclusionThe refashioned foley catheter is a novel, available, and inexpensive stent that can be utilized for LTR cases for pediatric LTS. The newly described stent is soft, pliable with atraumatic insertion and easy endoscopic removal with minimal complications.

A new maneuver for classical laryngeal mask airway insertion: Prospective randomized study

Background/Aim: Laryngeal mask airway (LMA) has been frequently used for airway management. But the satisfaction of the insertion and trauma at insertion remain problems. We present a new insertion maneuver for classical LMA (cLMA) with a partially inflated cuff and examine its success and complication rate.&#x0D; Methods: In 4 months, 158 patients who were classified as ASA I–III and older than 18 years old and were planned for LMA were included in this study consecutively (according to the study design, one patient was excluded during the study). Emergency cases, patients with any contraindications with LMA, patients who were expected to undergo surgery for more than 2 h, patients with preoperative respiratory tract infection or sore throat, patients undergoing oral or nasal surgery, and patients with aspirated oropharyngeal secretions after removal of LMA was excluded from the study. Age, gender, height, weight, ASA scores, comorbidities, and the duration of anesthesia and surgery of the patients were recorded. One-hundred-fifty-seven consecutive patients were randomized into two groups by a coin toss [control group (group C) and study group (group S)]. The groups were compared in terms of LMA insertion success, the number of insertion attempts, the presence of blood on the LMA or in secretions, and postoperative sore throat. Classical Laryngeal Mask Airway was inserted with Brain’s standard technique in group C and with the new technique in group S. In the new technique, the head and neck of the patient were supported in a straight position, the mouth was opened, cLMA was held with a dominant hand from the tube part and inserted until the tip touches to the oropharynx. The index finger of the non-dominant hand was inserted into the mouth to pass by the cLMA and reach the tip of the cLMA. The tip of cLMA was directed to the caudal by the index finger. Then, cLMA was inserted by the guidance of the index finger until it reached the triangular base of the oropharynx.&#x0D; Results: There was no statistically significant difference in terms of demographic data and placement success; placement success was better in the study group (100% versus 98.6% and P = 0.45). Similarly, the count of attempts was better in the study group. The mean attempt number was 1.11 in group S and 1.28 in group C (P = 0.02). Also, blood on LMA was seen to be more common in group C (P = 0.04). There were no statistical differences in sore throat, but it was less seen in group S.&#x0D; Conclusion: The new maneuver was better than the standard technique and easy to use in daily practice.

A Novel Tube Insertion Technique for Glaucoma Drainage Device Implantation.

Early hypotony after non-valved glaucoma drainage device (GDD) implantation for complex glaucomatous eyes with labile aqueous production can lead to significant visual morbidity. We therefore sought to report the early postoperative outcomes of a novel surgical technique that allows atraumatic insertion of non-valved GDDs through a much smaller 25-gauge scleral track, to minimize entry site leakage and improve safety. Retrospective case series of 15 consecutive cases undergoing non-valved GDD insertion into the anterior chamber using a previously unreported technique. All eyes underwent successful GDD insertion using our novel technique, with no intraoperative complications. The mean preoperative intraocular pressures (IOP), at day 1, week 1 and week 3 were 31.4, 22.4, 23.7, and 25.6 mm Hg, respectively. A statistically significant IOP reduction was achieved at day 1, week 1 and week 3 postoperatively ( P <0.05) without any observed leakage at the scleral entry site. One eye (6.7%) with complex panuveitic glaucoma developed early hypotony (5mm Hg) with shallow choroidal detachments on day 1. This was successfully managed with 1 intracameral ophthalmic viscoelastic device injection given at the slit-lamp and no further intervention. This novel single needle-docking intraocular insertion manoeuvre is an easily adoptable technique to make GDD insertion through a smaller 25-gauge water-tight scleral track more efficient and less traumatic. The technique reduces scleral distortion and therefore improves surgical safety particularly in eyes with complex secondary glaucoma.

Feasibility Study of Aerocapture at Mars with an Innovative Deployable Heat Shield

Performing orbital insertion around Mars using aerocapture instead of a propulsive orbit insertion maneuver allows the saving of resources and/or the increase of the payload mass fraction. Aerocapture has never been employed to date because of the high uncertainties in the parameters from which it depends, mainly related to atmospheric density modeling and navigation errors. The purpose of this work is to investigate the feasibility of aerocapture at Mars with an innovative deployable drag device, whose aperture can be modulated in flight, and to assess the effects of the main uncertainties on the success of the maneuver. This paper starts with the presentation of a parametric bidimensional analysis of the effectiveness of aerocapture, for which a wide range of uncertainty levels in the atmospheric density and the ballistic coefficient are considered. Then, an application to a real mission scenario is carried out, including the error of the targeting maneuver performed at the limit of the sphere of influence of the planet. The analyses show the strong influence of the uncertainties in the atmospheric density and the ballistic coefficient, which significantly narrow the solution space and limit its continuity. However, viable solutions for aerocapture can still be identified, even in the worst conditions.

Roundabout Crossing With Interval Occupancy and Virtual Instances of Road Users

Although autonomous vehicle technology has evolved significantly in recent years, the navigation of self-driving vehicles in complex scenarios is still an open issue. One of the major challenges in these conditions is safe navigation on roads open to public traffic. The main issue is the interaction of the autonomous vehicle with regular traffic, as the behaviors and intentions of human-driven vehicles are hard to predict and understand. In this paper we propose a strategy to allow an autonomous vehicle to safely cross a multi-lane roundabout. Our approach uses a High-Definition (HD) map to predict at lane level the future situation, harnessing the concept of virtual instances of road users, which is a key concept in anticipating the situation in a roundabout that can be represented by a navigation graph with loops. This paper presents a methodology that uses intervals representing road occupancy by vehicles, with the road being widened to reflect uncertainties in localization. Our method safely avoids collisions and guarantees that no priority constraints are violated during the insertion maneuver. Moreover, the method does not provide an overly cautious insertion policy, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">i.e.</i> , an autonomous vehicle does not wait for a long time before the insertion. The performance of our strategy was evaluated using the SUMO simulation framework. To better evaluate the complexity of the simulation scenario, a highly interactive vehicle flow was generated using real dynamic traffic data from the INTERACTION dataset. We report real tests carried out with an experimental self-driving vehicle on a test circuit. Our results show that this approach is easy to integrate into an embedded system and that it allows roundabouts to be crossed with a high level of safety.

Design and sensitivity analysis of spacecraft swarms for planetary moon reconnaissance through co-orbits

This work presents an automated mission design architecture for global surface mapping missions to planetary moons. Such missions need to address three important challenges: virtually absent spheres of influence, tidal locking, and self-shadowing. Therefore, a complex task such as global surface coverage is better handled using the swarm approach. The design of a swarm mission for such a dynamic environment is challenging. For this reason, we developed the Integrated Design Engineering and Automation of Swarms (IDEAS) software to facilitate the automated end-to-end design of swarm mission concepts. Specifically, it will use a sub-module known as the Automated Swarm Designer module to find optimal swarm configurations suited for a given mission. In our previous work, we developed the Automated Swarm Design module to find swarm configurations for asteroid mapping operations. Here, we will evaluate the capability of the Automated Swarm designer module to design missions to planetary moons, and also examine the sensitivity of the generated optimal design to various perturbations. Specifically, we explore the design space of resonant co-orbits where the spacecraft will have planned periodic encounters with the planetary moon due to the natural dynamics. The swarm will be deployed on resonant co-orbits using an aeroassist from the central planet. the maneuver cost with this deployment is broken down into two maneuvers: a planar orbit insertion maneuver using aerobraking, and an orientation change maneuver required to facilitate a planar orbit capture. The design space of such missions is examined, and the principles are illustrated using numerical case studies of a global surface mapping mission to the Martian moon Deimos. Using the described principles, a spacecraft swarm mission to map 90 % of the surface of Deimos is designed. The designed swarm consists of 5 spacecraft, which have a maximum estimated orientation change Δv of 1.97 km/s, and a worst-case orbit insertion Δv of 0.848 km/s if aerobraking is used. Overall implications on the mission, such as fuel requirements, and aerobraking timespans are then studied. Finally, the sensitivities of the designed swarm to different perturbations are studied, and peak disturbances that lead to coverage deterioration below a threshold of 80 % are noted.

Extended Robust Planetary Orbit Insertion Method Under Probabilistic Uncertainties

Planetary orbit insertion maneuver is one of the most critical events in deep space exploration missions. Once the spacecraft fails to decelerate enough to stay in the planetary orbit, it escapes from the vicinity of the planet. In some cases, such as the Akatsuki mission of Japan Aerospace Exploration Agency (JAXA), a feasible recovery trajectory was found after an engine malfunction; however, in many cases, the mission may fail because the spacecraft will end its mission life before reencountering the planet. To mitigate the risk, researchers have studied robust orbit insertion strategies, which reduce the total probabilistic by sacrificing nominal and shorten the flight time to reencounter the planet. Previous studies consider the possibility that planetary orbit insertion fails completely and use resonant trajectories as the recovery trajectories. This paper extends the robust orbit insertion method by implementing V-infinity leveraging transfers as the recovery trajectories. This extension enables to treat general probability models that describe the partial failures of orbit insertion maneuvers. The numerical example of JAXA’s Martian Moons Exploration mission shows that the proposed method enhances performance, namely, the expected and , as well as robustness.

Automated design architectures for co-orbiting spacecraft swarms for planetary moon mapping

This work describes the design and optimization of spacecraft swarm missions to meet spatial and temporal visual mapping requirements of missions to planetary moons, using resonant co-orbits. The algorithms described here are a part of Integrated Design Engineering and Automation of Swarms (IDEAS), a spacecraft swarm mission design software that automates the design trajectories, swarm, and spacecraft behaviors in the mission. In the current work, we focus on the swarm design and optimization features of IDEAS, while showing the interaction between the different design modules. In the design segment, we consider the coverage requirements of two general planetary moon mapping missions: global surface mapping and region of interest observation. The configuration of the swarm co-orbits for the two missions is described, where the participating spacecraft have resonant encounters with the moon on their orbital apoapsis. We relate the swarm design to trajectory design through the orbit insertion maneuver performed on the interplanetary trajectory using aero-braking. We then present algorithms to model visual coverage, and collision avoidance in the swarm. To demonstrate the interaction between different design modules, we relate the trajectory and swarm to spacecraft design through fuel mass, and mission cost estimations using preliminary models. In the optimization segment, we formulate the trajectory and swarm design optimizations for the two missions as Mixed Integer Nonlinear Programming (MINLP) problems. In the current work, we use Genetic Algorithm as the primary optimization solver. However, we also use the Particle Swarm Optimizer to compare the optimizer performance. Finally, the algorithms described here are demonstrated through numerical case studies, where the two visual mapping missions are designed to explore the Martian moon Deimos.

Mission Design and Analysis for Mars Orbiter Mission

Mars orbiter mission (MOM) is India’s first interplanetary mission. MOM was planned to be launched by Polar Satellite Launch Vehicle (PSLV) into an Earth elliptic parking orbit (EPO) in Oct-Nov 2013 utilizing the 2013 opportunity to rendezvous with Mars. This paper covers the mission design and analysis carried out for the MOM/PSLV mission. New software tools were designed and developed to design interplanetary trajectories, to generate total maneuver strategy from earth EPO to target Martian orbit, to design trajectory correction maneuvers in interplanetary cruise phase targeting to desired B-plane parameters and to design Mars orbit insertion maneuver. The launch window and optimum EPO requirements were generated and provided to PSLV. The target Martian orbit was selected considering all the specified s/c platform and payload constraints. Maneuver strategies were designed considering operational constraints and total mission profiles were studied comprising orbital events and Earth-Satellite-Sun geometry and distance characteristics. Non-nominal mission scenarios were studied, comprising launcher dispersions, missing any of the earth phase burns and backup maneuver plans generated. Mars orbit insertion maneuver strategy was designed considering nominal and non-nominal scenarios. MOM was launched on 5th November, 2013 and successfully captured into the desired Martian orbit on 24th September, 2014 achieving the main technological objective of the mission in India’s first interplanetary endeavor.

Observational Arc-Length Effect on Orbit Determination for Korea Pathfinder Lunar Orbiter in the Earth-Moon Transfer Phase Using a Sequential Estimation

In this study, the observational arc-length effect on orbit determination (OD) for the Korea Pathfinder Lunar Orbiter (KPLO) in the Earth-Moon Transfer phase was investigated. For the OD, we employed a sequential estimation using the extended Kalman filter and a fixed-point smoother. The mission periods, comprised between the perigee maneuvers (PM) and the lunar orbit insertion (LOI) maneuver in a 3.5 phasing loop of the KPLO, was the primary target. The total period was divided into three phases: launch–PM1, PM1–PM3, and PM3–LOI. The Doppler and range data obtained from three tracking stations [included in the deep space network (DSN) and Korea Deep Space Antenna (KDSA)] were utilized for the OD. Six arc-length cases (24 hrs, 48 hrs, 60 hrs, 3 days, 4 days, and 5 days) were considered for the arc-length effect investigation. In order to evaluate the OD accuracy, we analyzed the position uncertainties, the precision of orbit overlaps, and the position differences between true and estimated trajectories. The maximum performance of 3-day OD approach was observed in the case of stable flight dynamics operations and robust navigation capability. This study provides a guideline for the flight dynamics operations of the KPLO in the trans-lunar phase.

Tracheal intubation with the McGrath MAC X-blade videolaryngoscope in morbidly obese and nonobese patients

Background/aimIncreased body mass index (BMI) and neck circumference are the two independent predictors of difficult intubation. McGrath MAC X-Blade is a videolaryngoscope specifically designed for difficult intubations.Materials and methodsEighty patients with the American Society of Anesthesiologists (ASA) physical status I–III undergoing elective surgery requiring endotracheal intubation were enrolled in the study. Patients were divided into two groups, nonobese (BMI < 30) and morbidly obese (BMI > 35). All patients were intubated with the McGrath MAC X-Blade in both groups. View optimization and tube insertion maneuvers such as reinsertion of the device, slight removal of the device, cricoid pressure, handling force, 90° anticlockwise rotation of the tube, use of stylet, and head flexion maneuvers were recorded. Cormack–Lehane grades, insertion times, intubation, and total intubation times were recorded. The hemodynamic changes and postoperative minor complications were also recorded.ResultsBody mass index, neck circumference, Mallampati scores, and ASA physical status were statistically higher in the morbidly obese group (P < 0.001 and P < 0.05). Sternomental distances were shorter in the morbidly obese (P < 0.05). Cormack–Lehane grades were comparable among the groups. The morbidly obese patients required more reinsertion attempts and cricoid pressure maneuvers during intubation than the nonobese patients (P = 0.019 versus P = 0.012, respectively). Slight removal of the device, handling force, use of the stylet, 90° anticlockwise rotation of the tube, and head flexion maneuvers were also helpful in both groups. Although device insertion times were similar between the groups, intubation and total intubation times were longer in the morbidly obese group (P = 0.009 and P = 0.034, respectively). The groups were comparable in hemodynamic changes and postoperative minor complications.ConclusionThe McGrath MAC X-Blade videolaryngoscope could safely be used both in nonobese (BMI < 30) and morbidly obese (BMI > 35) patients with the aid of some key maneuvers and with a statistically significant but clinically negligible prolongation of the intubation time.

Tour Design Techniques for the Europa Clipper Mission

Europa is one of the most scientifically interesting targets of the solar system, as it may possess what are thought to be the three necessary ingredients for life: an extensive ocean of liquid water, an energy source, and a suite of biogenic elements. To explore the habitability of Europa, NASA is developing the Europa Clipper mission, currently scheduled to be launched in 2023. Europa resides deep inside the gravity well of Jupiter, in a region of the magnetosphere with many trapped ionized particles that when accelerated to near relativistic speeds result in a radiation environment detrimental to spacecraft electronics; a Europa orbiter mission that would continuously reside in the same radiation environment as Europa would require a large amount of for an orbit insertion maneuver, and would only return limited science data before being critically exposed to radiation. To mitigate these issues, Europa Clipper will instead use a high number of Europa flybys, connected by resonant and nonresonant transfers. Science data are collected during high-radiation Europa flybys, and returned to Earth during the rest of the highly elliptical Jovian orbits, at a much lower radiation dose exposure. This paper will present several tour techniques developed for the design of the Europa Clipper flyby trajectory. In particular, this paper will describe different ways to perform fast line-of-apsides rotations; a new approach to improve the coverage of Europa’s trailing and leading edges; parametric studies of the expected radiation dose and time of flight as function of the Europa resonance; and a quick way to estimate the radiation dose for complete Jovian tours. Other techniques, which were already presented in previous papers, will be reviewed for completeness. Then some of the new approaches will be implemented in the 18F17 tour.

Novel Operation Support Robot with Sensory-Motor Feedback System for Neuroendovascular Intervention

Robotic technology is rapidly developing in the medical field, particularly contributing to support operative intervention using the da Vinci system during endoscopic surgery. Neuroendovascular intervention robot surgery is preferred when aiming to reduce radiation exposure among surgeons. We developed a prototype of a support robot with 2 independent slaves manipulating both the microcatheter and microguidewire connected with the remote master driver with 2 joysticks. This design simulates usual catheterization with both hands. The slave manipulator has a sufficient output force >1 N to reproduce the exact master intervention without slip and delay. This machine has a unique function that indicates the reaction force of the resistance on wire stuck using the sensor system. We investigated the master-slave response, reliability of the force gauge, and degree of slippage of the slave motion on the table and checked the controllability, safety, and reproducibility of microcatheterization and insertion maneuver into the experimental aneurysm in the invivo silicone vessel model. We realized the well master-slave response with a stable driving speed of the microguidewire at approximately 1 mm/s and with linear correlation between the output voltage and driving force. Also, we confirmed the well safety function to avoid the overloading to the vascular wall with the slippage of the slave roller on loading >1 N pushing force. Successful microcatheterization and insertion into the aneurysm model was performed in the wet vascular model corresponding to the 3-dimensional handling without excessive stress to the vascular or aneurysmal wall. Neuroendovascular intervention requires delicate power adjustment with fine finger control. Our support robot for neuroendovascular interventions demonstrated the accurate reproducibility of the operator's maneuver and safe operation in the vascular model using the sensor system. This system will realize the neurointervention without human operators in the AngioSuite and may facilitate telesurgery with remote control in the near future.

Magnitude of Airway Problems at a University Teaching and Referral Hospital Recovery Room of Low Resource Setting-A Cross Sectional Study

Background: Airway management is a basic life-saving intervention which is used when the patient’s breathing effort is compromised due to various reasons. Postsurgical patients are at risk of developing airway problems due to co-morbidities, intraoperative complications, surgery and anaesthetic drug effects. The severity of illness, analgesic drugs like narcotics and postoperative standard of monitoring may impact on breathing process of the patients. We aimed to assess the magnitude of airway problems at the recovery room. Methods and material: Cross sectional study conducted at a referral hospital recovery room, 2014. Standardized checklist used for data collection. All patients with airway problem who admitted at the recovery room during the study period were included in the study. Descriptive statistics and Chi-square were used. Results: One hundred seventy seven patients developed airway problems over five months duration. Of these, 47.5%, 32.2%, and 20.3% patients developed mild, moderate and severe airway problems respectively. The major airway problems were desaturation (62.7%), respiratory arrest (14.7%), aspiration (18.1%), bronchospasm (3.4%) and laryngospasm (1.1%) respectively. Factors associated with severity of airway problems were ASA status (P=0.031), type of trauma (P=0.026), intraoperative analgesia (P=0.020) and type of patient (P=0.049). The interventions made were ETTI or LMA (35%) patients, nasopharyngeal airway insertion (21.5%), oral airway (14.1%), oxygen supplementation (10.2%), surgical airway (9.6%), recovery position (7.3%) and emergency airway manoeuvre (2.3%) respectively. Anaesthetists involved in airway management in 30.5% of patients. Conclusion: The magnitude of airway problem was high. We recommend the availability of well trained staff for airway management and fulfilment of basic equipments and drugs for patient monitoring and resuscitation. High airway problems are an alarm for the need for well-equipped recovery room with well trained staff, patient monitoring and resuscitation materials.