Eleonora Botta

University at Buffalo, The State University of New York | SUNY Buffalo · Department of Mechanical and Aerospace Engineering

An increasing concern for space-based missions is the potential of collisions with space debris. Long-term mitigation of this risk can be achieved by removing large debris from orbit, as, in particular, collisions involving these can significantly increase the number of smaller debris in orbit. One method of removal involves an active craft capturi...

In this paper, a distributed computing framework that exploits high-performance compute clusters and employs a Distributed Multiple-Swarm Particle Swarm Optimization (DMSPSO) algorithm is proposed for solving two-point boundary-value problems in astrodynamics. The DMSPSO algorithm performs a search of the solution space by attempting to minimize th...

This work validates lumped-parameter models and cable-based models for nets against data from a parabolic flight experiment. The capabilities of a simulator based in Vortex Studio, a multibody dynamics simulation framework, are expanded by introducing i) a lumped-parameter model of the net with lumped masses placed along the threads and ii) a flexi...

In this paper, a Q-Law-based feedback control algorithm is proposed for incorporating sun-angle constraints that ensure proper alignment of the solar panels of the spacecraft with the sun when employing solar electric propulsion. Analytical expressions for the sun-angle-constrained Q-Law-based control are made available through the application of a...

Tethered systems, such as tethered harpoons or nets, are promising methods to capture uncooperative space debris, but suffer from complicated post-capture dynamics and control; control strategies could benefit from knowledge of the mass moments of inertia of the target debris, usually unknown without estimation. In this work, an Unscented Kalman F...

The earth's orbit is becoming increasingly crowded with debris that poses significant safety risks to the operation of existing and new spacecraft and satellites. The active tether-net system, which consists of a flexible net with maneuverable corner nodes launched from a small autonomous spacecraft, is a promising solution for capturing and dispos...

In this paper, Particle Swarm Optimization with energy-to-fuel continuation is proposed for initializing the co-state variables for low-thrust minimum-fuel trajectory optimization problems in the circular restricted three-body problem. Particle Swarm Optimization performs a search of the solution space by minimizing the weighted sum of squares of t...

In this paper, Particle Swarm Optimization with energy-to-fuel continuation is proposed for initializing the co-state variables for low-thrust minimum-fuel trajectory optimization problems in the circular restricted three-body problem. Particle Swarm Optimization performs a search of the solution space by minimizing the weighted sum of squares of t...

An increasing concern for space-based missions is the potential of collisions with space debris. Mitigation of this risk can be achieved by removing large debris from orbit, as, in particular, collisions involving these can significantly increase the number of smaller debris in orbit. One method of removal involves an active craft capturing and tow...

In this paper, a distributed computing framework that exploits high-performance compute clusters and employs a Distributed Multiple-Swarm Particle Swarm Optimization (DMSPSO) algorithm is proposed for solving two-point boundary value problems in astrodynamics. The DMSPSO algorithm performs a search of the solution space by attempting to minimize th...

It is well known that space debris is a risk to the safety of spacecraft in orbit. To increase the safety of space operations, one promising method involves removal and disposal of debris via a tethered system, which may include tethered harpoons or tether nets. Control of debris is complicated by the fact that debris is uncooperative and unrespons...

Space debris is often uncooperative and unresponsive, necessitating the understanding of its motion for successful post-capture control in an active debris removal mission. To this end, the inertia tensor of the captured debris object must be estimated, which is particularly challenging when the connection between chaser and target is not rigid, su...

Retrieval of tethered satellite systems is an unstable process. Several complex control methods have been proposed to stabilize this process. Recently, a simple, heuristic bang–bang control algorithm was found to be effective at significantly reducing libration angles by introducing short periods of extension during the retraction phase. In this pa...

Space debris is often uncooperative and unresponsive, necessitating the understanding of its motion for successful post-capture control in an active debris removal mission. To this end, the inertia tensor of the captured debris object must be estimated, which is particularly challenging when the connection between chaser and target is not rigid, su...

Tether-net launched from a chaser spacecraft provides a promising method to capture and dispose of large space debris in orbit. This tether-net system is subject to several sources of uncertainty in sensing and actuation that affect the performance of its net launch and closing control. Earlier reliability-based optimization approaches to design co...

Drone misuse and trespass in areas such as airports and military bases is becoming a pressing concern. A proposed solution to this issue is a drone system that is capable of autonomously flying and capturing other target drones by means of ejected tethered nets. Components of this system include a pressurized-air powered net launcher device, an on-...

Indirect optimal control methods rely on the solution of two-point boundary-value problems (TPBVP) and reduce unknowns to a small set of co-state variables which are known to exhibit extreme sensitivity. In this paper, heuristic optimization algorithms are exploited, together with recently proposed homotopy continuation techniques, to produce a qua...

Capture of debris via a net is one of the most promising Active Debris Removal methods. However, it is crucial to ensure that successful target capture is accomplished by the system even in the presence of uncertainties. The aim of this study is to understand the limitations of the tether-net system in capturing space debris and analyze its robustn...

Tether nets are one of the most promising technologies proposed for the removal of large objects from Earth orbit. Before net-based debris removal missions can be pursued, work is required to understand the behavior of nets in low gravity environments. This paper discusses the validation of a simulator, making use of lumped parameter modeling techn...

Tether-net launched from a chaser spacecraft provides a promising method to capture and dispose off large space debris in orbit. This tether-net system is subject to several sources of uncertainty in sensing and actuation that affect the performance of its net launch and closing control. Earlier reliability based optimization approaches to design c...

Mission design and optimization for spacecraft equipped with low-thrust propulsion is a complex problem. Among the proposed solutions, indirect methods apply calculus of variations and Pontryagin's maximum principle to analytically derive the necessary conditions for optimality, introducing additional co-state variables and formulating the problem...

View Video Presentation: https://doi.org/10.2514/6.2021-3103.vid Tether-nets deployed from a chaser spacecraft have been proposed as a promising technical solution to capture space debris in recent years. The success of this (usually one-shot) process however depends on the ability to perform an optimal launch and closure of the tether-net, subject...

Tether retraction in a tethered satellite system is known to be an unstable process. While many complex control algorithms attempt to eliminate the libration angle during retraction, a simple control algorithm is proposed here to only reduce the oscillations. Reducing the angle, rather than eliminating it entirely, may lead to lower delta-V require...

Before net-based debris removal missions are put in place, large simulation studies are needed to analyze the reliability of capture and define preferred designs and capture conditions. Therefore, evaluation of capture success in a simulation environment has to be automated. In this paper, a capture quality index apt to the quantitative evaluation...

The growth of space debris in Earth's orbit is recognized as a serious threat to future space missions. To contain the growth of space debris in the long term, active removal of large defunct spacecraft is needed. A promising solution to this problem is the use of tether-nets. In the envisaged mission, a net is released from a chaser spacecraft tow...

Before net-based debris removal missions are put in place, large simulation studies are needed to analyze the reliability of capture and define preferred designs and capture conditions. Therefore, evaluation of capture success in a simulation environment has to be automated. In this paper, an improved capture quality index apt to the quantitative e...

One of the most promising strategies for Active Debris Removal in Low Earth Orbits is the use of nets. In this work, a set of metrics are proposed to analyze the output space of simulations of net-based debris capture scenarios to determine capture success, based on geometrical analysis of the simulated net at various time steps. An overall index i...

A proposed solution to capture large debris is tether nets. This paper validates a simulator for the deployment of a net in space, implemented with the multibody dynamics simulation tool Vortex Dynamics. The dynamics of the simulated net, modeled with a lumped parameter approach, is compared to data taken during a parabolic flight experiment. Resul...

One of the most promising techniques to capture large debris on orbit consists in the use of tether-nets. With this concept currently at a medium technological readiness level only, numerical studies on tether-net removal missions are still needed. This paper presents a versatile simulator developed with the aim of gaining insight into the dynamics...

For containing the growth of space debris, which jeopardizes operation of spacecraft, the active removal of large and massive derelict satellites and launcher upper stages is needed. A promising technology for this endeavor is the use of tether-nets. In this concept, a tether-net is thrown from a chaser spacecraft in the proximity of a target debri...

In this paper, the deployment dynamics of nets in space is investigated through a combination of analysis and numerical simulations. The considered net is deployed by ejecting several corner masses and thanks to momentum and energy transfer from those to the innermost threads of the net. In this study, the net is modeled with a lumped-parameter app...

This research addresses the design and testing of a debris containment system for use in a tether-net approach to space debris removal. The tether-net active debris removal involves the ejection of a net from a spacecraft by applying impulses to masses on the net, subsequent expansion of the net, the envelopment and capture of the debris target, an...

A promising method to mitigate the space debris problem is to actively capture and remove debris by means of tether-nets. The chaser-tether-net-debris system is modeled with rigid bodies connected by constraints; the tether can be spooled in and out by controlling a winch on the chaser. Through dynamics simulation, this paper analyzes the effect of...

A proposed method for containing the growth of space debris, which jeopardizes operation of spacecraft, is the active debris removal of massive derelict spacecraft and launcher upper stages by means of tether nets. The behavior of nets in space is not well known; therefore, numerical simulation is needed to gain understanding of deployment and capt...

Tether-nets are considered a promising technology to capture large and massive tumbling space debris from orbit. These flexible devices are designed to be thrown from a dedicated spacecraft towards the target debris by imparting initial velocity to several corner masses and possibly to the net itself. The net is deployed thanks to momentum and ener...

Tether-nets are one of the more promising methods for the active removal of space debris. The aim of this paper is to study the dynamics of this type of systems in space, which is still not well-known and the simulation of which has multiple outstanding issues. In particular, the focus is on the deployment and capture phases of a net-based active d...

One proposed method to mitigate the space debris problem is to actively capture and remove debris by means of tether-nets. In this paper, the effectiveness of the capture maneuver in multiple net deployment and debris tumbling conditions is evaluated. The sensitivity study is performed by means of simulations based on a lumped-parameter modeling ap...

A proposed method for containing the growth of space debris, which jeopardizes operation of spacecraft, is the active debris removal of massive derelict spacecraft and launcher upper stages by means of tether-nets. The behavior of such systems in space is not well-known; therefore, numerical simulation is needed to gain understanding of deployment...

In this chapter we wrap up our literature investigation, pointing out the key focuses and requirements to be considered. We will go through our evaluations upon actuators, sensors, control systems and we will present some designs examples. Although literature is rich in studies on limbs exoskeletons aimed to several target applications, (such as re...

Environmental conditions and pressurized spacesuits expose astronauts to problems of fatigue during lengthy extravehicular activities, with adverse impacts especially on the dexterity, force and endurance of the hands and arms. A state-of-the-art exploration in the field of hand exoskeletons revealed that available products are unsuitable for space...

Environmental conditions and pressurized spacesuits expose astronauts to problems of fatigue during lengthy extravehicular activities, with adverse impacts especially on the dexterity, force and endurance of the hands and arms. A state-of-the-art exploration in the field of hand exoskeletons revealed that available products are unsuitable for space...

This chapter deals with the identification of the requirements that drive the design of the hand exoskeleton to help crewmembers during Extra-Vehicular Activities (EVAs). The requirements were identified by means of literature review as well as interviews to users and stakeholders. After an introduction to EVAs, the method followed for the design i...

Starting from the user’s requirements previously defined, a new soft robotics approach was chosen and developed in order to overcome the criticalities arisen in the analysis of the state of the art. One of the key points of soft robotics is biomimicry: in place of heavy, rigid and noisy motors, artificial muscles are in charge of the movement of th...