Abstract Lower-body exoskeleton control that adapts to users and provides assistance-as-needed can increase user participation motor learning allow for more effective gait rehabilitation. Adaptive model-based methods have previously been developed consider a user’s interaction with an exoskeleton; however, the predefined dynamics models required are challenging define accurately, due complex nonlinearities of human-exoskeleton interaction. Model-free deep reinforcement (DRL) approaches...

Recent efforts in on-orbit servicing, manufacturing, and debris removal have accentuated some of the challenges related to close-proximity space manipulation. Orbital threatens future endeavors driving active missions. Additionally, refueling missions become increasingly viable prolong satellite life mitigate generation. The ability capture cooperative non-cooperative spacecraft is an essential step for or In capture, collision avoidance remains a challenge during trajectory planning...

Patient-specific control and training on lower body exoskeletons can help improve a user's gait during post-stroke rehabilitation by increasing their amount of participation motor learning. Traditionally, adaptive techniques have been used to provide personalization synchronization with exoskeleton users, but they require predefined dynamics models the user exoskeleton. However, these be difficult accurately define due complexity human-robot interaction. Most recently deep reinforcement...

Safety and prevention of injuries should always be considered in a firefighting environment due to the hazardous conditions experienced on fireground. These environmental lead an increased risk contracting job-related illnesses. This review article focuses evaluating from statistical perspective potential solutions found literature how they decrease likelihood impact occupational injuries. Investigating, identifying, prioritizing most common activities leading injury, nature body parts...

In this paper, asteroid redirection methods are systematically compared and analyzed to assess their viability for a near-Earth mission. The intent is examine the benefits of spacecraft formation redirecting an orbit in Earth-Moon system order exploit resources. primary will be studied terms characteristics population, they within resource exploitation framework with respect free-flying landed strategies. Such investigated based on major criteria mission design, detailed assessment each...

This paper investigates the accessible low-thrust transfer trajectories for a near-Earth asteroid mission. The target asteroids considered are Arjuna-type asteroids, which characterized by their Earth-like orbital paths including low eccentricity and inclination. range is specific of semimajor axes angles to provide an overall assessment potential Arjuna domain. A single hovering ion beam spacecraft employed task redirection. method uses continuous thrust over duration maneuver redirect...

This paper provides a systematic comparison of the primary asteroid redirection techniques from perspective resource exploitation. The goal is to examine methods for near-Earth stable and easily accessible orbit in Earth-moon system order exploit resources. context exploitation clear constraints on mission, can be established within this scope. describes each method, considers major criteria mission design. Moreover, Monte Carlo analysis performed assess some attributes concerning...

Abstract Stroke is a leading cause of disability, and robotic lower body exoskeletons have been developed to aid in gait rehabilitation. The simulation modeling testing processes are often deployed separately. This introduces additional steps which can hinder on-the-fly customization patterns required for individualized In this paper, we present centralized control architecture integrates both the simulated model exoskeleton hardware exoskeletons. allows ease simulating, adapting, deploying...

Space debris pose a serious threat to the safety and operations of space assets. Debris removal strategies post-mission disposal are becoming more pertinent due catastrophic collisions explosions that have occurred in orbit past two decades. An important aspect any mission or maneuver is ability object deorbit reenter into Earth's atmosphere controlled manner over an uninhabited area. This considered one safest options since reentry can ensure falls specific low-populated unpopulated regions...

This paper determines the near-optimal transfer trajectory of a Near-Earth Asteroid (NEA) to an orbit in Earth-Moon system through use ion beam redirection method. The method is hovering approach asteroid redirection. operates two diametrically opposed thrusters. mission targets Arjuna-type asteroids, and uses sample asteroid, 2013 RZ53, demonstrate applicability pseudo-equinoctial shaping orbital transfer. from its initial about Sun final divided into phases using patched conics...

In order to accomplish most asteroid redirection missions, rotational control of the body is required. Small near-Earth asteroids tend exhibit a significant range and tumbling properties. This work provides an analysis detumbling using formation spacecraft. Through orbiter three landed thruster spacecraft, low-thrust maneuver performed on two illustrative asteroids. The scenarios are designed such that they reflect characteristics possible scenarios. particular geometries, densities, angular...

This paper discusses the applicability of some asteroid redirection methods, prominently studied in literature, to orbital debris removal. The tasks and removal share common goal controlled an uncooperative target. Three methods are systematically compared analyzed assess their viability for reentry mission, i.e., ion beam shepherd, laser sublimation, tugboat. These investigated terms characteristics population based on major criteria mission design objects. In addition, uncertainty...

A smoothed-particle hydrodynamics (SPH) modeling technique was applied in conjunction with the Johnson–Holmquist (JH-2) ceramic material constitutive model to replicate fracture of soda-lime glass a milling manufacturing process. Four-point bending tests were conducted validate bulk properties prior its implementation ABAQUS CAE™ Explicit (Version 2017). The JH-2 replicated load and time for four-point cases as per ASTM C158. This study showed how SPH combination validated process simulation...