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Rendezvous, Proximity Operations and Space Robotics Research at Florida Institute of Technology

Markus Wilde

Department of Aerospace Engineering, Physics and Space Sciences

Florida Institute of Technology

mwilde@fit.edu

321-674-8788

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The ORION Lab

Vision StatementBecome a leading research laboratory for spacerobotics, rendezvous and proximity operations in theU.S. and the world and the go-to partner for U.S.industry and government.

Mission StatementDevelop, implement and demonstrate prototypetechnologies for guidance, navigation, control,robotics and mission operations to turn smallsatellites into the PT Boats of the 21st century.

Space asset protection and defenseSpace object inspectionAnomaly resolutionOn-orbit servicingIn-space assemblyAssisted maneuveringDebris removal

O rbital

R obotic

I nteraction

O n-orbit servicing and

N avigation

Laboratory

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Lab Overview

• Spacecraft proximity maneuver kinematics and dynamics testbed

– Workspace: 9.4 m × 9.7 m × 2.7 m

– Maneuver Kinematics Simulator

– Integrated Flat-Floor Motion Dynamics Testbed

– High-Precision Air-Bearing Table

• Orbital lighting simulation

• Real-time object tracking using OptiTracksystem

• Control Room with space dedicated to prototype system operators

• Hardware integration and storage spaces

• All lab components interconnected by WiFi

• Network ports for remote connectivity available

Student /

Researcher

Office

Control Room

Experiment

Preparation

Room

Spacecraft Maneuver

Kinematics Simulator

Targ

et

Ch

aser

ORION Simulator

Lab Facilities

9.4

m

9.6 m

Integrated

Flat-Floor

Motion

Dynamics

Testbed

Su

n S

imu

lato

r

Op

tiTra

ck

Sys

tem

High-Precision

Air-Bearing

Table

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Maneuver Kinematics and Dynamics Testbed

Stationary Pan-Tilt Head

(with Target Object)

Pan-Tilt Mechanism

2 DOF Motion Table

Integrated Acrylic Flat

Floor

High-Precision Air-Bearing Table

Lighting Simulation

OptiTrack System

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Maneuver Kinematics Simulator• Planar, gantry-based simulator for relative orbital

dynamics between two spacecraft

• Combination of motion table and pan-tilt mechanisms enable simulation of 3D viewing conditions.

• Workspace: 5.5 m x 3.5 m

• Pan-tilt mechanisms for test articles of up to 20 kg, supplied with 120 V AC and Ethernet

• Pan-tilt heads can be removed to support other mechanisms, such as robotic manipulators

• Enables sensor testing, GNC law verification, teleoperation experiments, etc.

• Total 6 degrees of freedom

Degree of Freedom Motion Range Max. Vel. Max. Accel.

Chaser x translation 5.5 m 0.25 m/s 1 m/s2

Chaser y translation 3.5 m 0.25 m/s 1 m/s2

Chaser pitch ±90° 60°/s 60°/s2

Chaser yaw inf. 60°/s 60°/s2

Target pitch ±90° 60°/s 60°/s2

Target yaw inf. 60°/s 60°/s2

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Maneuver Dynamics Simulators

Two air-bearing motion dynamics testbeds enable experiments of spacecraft maneuver dynamics and contact dynamics.

Integrated Flat Floor• 5.9 m x 3.6 m acrylic flat floor within the frames of the

Maneuver Kinematics Simulator• Enables coordinated use of gantry mechanism with

air-bearing vehicles for kinematics/dynamics experiments such as robotic capture of debris objects

High-Precision Air-Bearing Table• 3.6 m x 1.8 m tempered glass plate on optical bench

with pneumatic vibration isolators• Enables experiments in contact dynamics, spacecraft

controls, formation flight, docking/capture, etc

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Planar Air-Bearing Vehicles

• Planar air-bearing vehicles (ABV) for formation flight and docking / capture experiments

• Propulsion: custom thrusters using compressed N2

• Attitude control: Thrusters or custom reaction wheels

• On-board computer: Intel i5

• Endurance: ~20 minutes

• Aluminum frame allows easy attachment of capture tools, docking interfaces, sensors, robot manipulators, etc.

ChaserTarget

Chaser and target air-bearing vehicles (ABV)

Custom N2 thrusters Custom reaction wheel

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Lighting Simulation

• Hilio D12 LED high-intensity light panel used to simulate orbital lighting conditions

• Light panel is daylight balanced

• Equivalent to 2000 W incandescent light

• Intensity sufficient to oversaturate dynamic range of cameras, produce stark light/shadow differences, and blind laser range finders.

• Lens inserts used to change the beam angle between 15° and 60°.

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OptiTrack System• 12-camera OptiTrack Prime 17W system tracks objects within the ORION Lab with

sub-millimeter and sub-degree accuracy

• Objects are defined by four infrared reflectors

• Real-time streaming of tracking data on the lab network

• Used in closed-loop control of the Maneuver Kinematics Simulator

• For formation flight and docking experiments, OptiTrack can be used as stand-in for relative navigation sensors

• For sensor testing, the OptiTrack data serves as ground truth

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Control Station

• ORION Control Room has a control station for the testbed and multiple workstations for equipment operators and test engineers

• Teleoperation console equipped with multiple input devices to support experiments in the teleoperation of ground, air, and space robots and vehicles.

• Operator at teleoperation console do not have direct sight of the testbed and all video and telemetry channels can feature artificial time delays.

Control Station Teleoperation Console

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R&D Thrusts

Overarching goal: Enable swarms of SmallSats to become agile, adaptable and flexible RPO and space robotic systems for commercial or national security applications.

Testbed Technologies

– Develop and test technologies enabling high fidelity simulation of spacecraft proximity maneuvering, maneuver dynamics, contact dynamics and spacecraft robotics

– Reduce uncertainty involved in deploying SmallSats with RPO and robotic capabilities

SmallSat technologies

– Rapid development and hardware-in-the-loop testing of proof-of-concept prototypes for SmallSat GNC, robotics and mission operations technologies

– Produce experimentally verified concepts for use by U.S. industry and government

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TESTBED TECHNOLOGIES

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6 DOF Air-Bearing Vehicle

• Enable 6 DOF simulation of maneuver dynamics and contact dynamics

• 3 DOF rotational motion (pitch and roll limited to ±30°) using hemispherical air bearing

• 2 DOF planar horizontal motion using planar air bearings

• 1 DOF vertical motion using counterbalancing deck and air-bearing pulley system with magnetic centering

• Wireless communication between all subsystems

Thrusters

Attitude Platform

Vertical Stand

Horizontal Base

Counterbalancing Deck

Guide Column

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Omnidirectional Flying Vehicle

• Spherical flying vehicle for decoupled linear and rotary motion

• Enables simulation of tumbling motion of spacecraft in formation flight, relative navigation and capture scenarios

• Spin-off: Control algorithms for omni-directional aerial vehicles, with utility in exploration / reconnaissance of underground complexes

Propellers

Tilt shafts

Slip rings

Electronics Compartment

Safety Cage

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SMALLSAT TECHNOLOGIES

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Cooperative Relative Navigation for Swarms

• Use of established spacecraft relative navigation methods and triangulation algorithms to enable in-swarm object tracking similar to OptiTrack or Vicon

• Satellites at the edges of the swarm will establish ad-hoc tracking network and determine position and orientation of all other swarm satellites

• Swarm satellites receive accurate and precise navigation data for path planning and maneuver control

– Swarm reconfiguration

– Safe approach of non-cooperative target objects within swarm

– Distributed capture / de-tumbling operations

• Capability will enable swarms of small satellites to characterize, approach and engage non-cooperative target objects

Non-cooperative,

tumbling space

object

Distributed visual

mapping, motion

characterization,

and object tracking

Autonomous,

distributed

trajectory planning

and approach GNC

Autonomous

capture and

detumbling

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Cooperative Point Cloud Processing

• Use of multiple swarm satellites equipped with 3D cameras (stereoscopic / time-of-flight) to produce point-cloud model of resident space object

• Point cloud will be processed to:

– Characterize target motion (tumbling axis and rates)

– Map geometry of target

– Identify surface features for capture, servicing, neutralization, etc.

• Capability enables swarms of small satellites to inspect, characterize, safely approach and engage non-cooperative resident space object

• Applications:– On-orbit servicing

– Debris removal

– Inspection

– Protection and defense

Visual and point cloud images of a target object in the ORION Lab

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Swiss Army Spacecraft Capture Tools

• Development of unconventional capture tools to enable small spacecraft to attach themselves to surfaces, apertures, mounting structures, etc. on any target object

• Will make robotic spacecraft adaptable for wide array target object size, geometry, motion, inertia, structural health, etc.

• Goal is to equip chaser spacecraft with toll changer and suite of different capture tools, similar to Swiss Army Knife

Rotary tool selector concept

Capture tool inspirations

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Piggy-Back Inspection and Repair Satellites

• Laboratory prototype for a remora-like inspection and repair satellite for large and expensive space assets.

• Vision: Equip major space assets with this inspection/repair/protection capability.

• Cerberus: small inspection and repair satellite equipped with modular robot manipulators and sensor packages, controlled by thrust-vectoring cold-gas system.

• Typhon: Support system for Cerberus, capable of capturing the inspection satellite, refueling its propellant tank and recharging its battery.

Thrust-vectoring system

Navigationsensors

Modular robotics payload

CerberusTyphon

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Spacecraft Refueling

• Spacecraft refueling during formation flight, instead of using hard docking of tanker onto client

• Increases operational flexibility and failure tolerance

• Robotic propellant transfer boom will form compliant connection and transfer propellant and state data between spacecraft

• Tanker and client are both under independent control

• Eliminates need for heavy capture/docking fixtures

• Client can abort refueling and disengage if tanker gets disabled

• One tanker can refuel multiple clients simultaneously

Experiment concept

Robotic transfer boom

Capture electromagnets (3)

Transfer nozzle

Guiding cone

Alignment pins (3)

Servos (5)

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Continuum Robots for Space Object Capture

• Rigid-link robot arms need complex end-effectors in order to be adaptable regarding target geometry, size, inertia and capture interfaces

• Capture of cylindrical upper stages (mostly in flat spin) or large, cuboid debris objects very challenging

• Continuum robots (tentacle robots) are designed to be inherently flexible, can wrap around target objects of almost any shape, and slowly despin/detumble

• Flexible, adaptable solution for debris removal, in-space assembly, assisted maneuvering, and protection/defense

Proof of concept experiment conducted in ORION Lab, in collaboration with Clemson University

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VR Command and Training Environment

• Console-based spacecraft commanding not suitable for dynamic operations with large number of satellites in congested and contested environment

• Pace of swarm and robotic spacecraft operations will be different than current spacecraft operations

• Controlling RPO from ground requires high level of situation awareness

• Concept: use virtual reality environment to control spacecraft RPO using interactive 3D models of spacecraft

– Virtual button pushes can engage sensors, mechanisms, etc.

– Operators can plan maneuver by drawing flight paths of rotating model in virtual space

– Collaboration of operators at distributed locations easily possible

– Subject matter experts (engineers, scientists, analysts) can be brought into operation

Interactive model of the chaser used to control the spacecraft in real time during RPO

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High-Agility SmallSat Thruster System

• Dynamic RPO require high spacecraft agility

• Agility of small satellite limited by available thruster systems

– Cold-gas/monopropellants:

• Large, heavy tank

• Pressurized tank risky for piggy-back launch

– Electric thrusters:

• Low thrust

• Not usable for dynamic RPO maneuvering

• Development of thruster “quads” using electrically ignited solid propellants and individually controlled nozzles

– Inherently safe

– Agile spacecraft translation and rotation control

• Design goals:

– Thrust: 1 N – 10 N

– Reload capability

– Full characterization using environment chamber, shaker and maneuver demonstrations

Combustion Chamber

Pellet storage and feed mechanism

Outer Casing

Universal attachment port

CathodeAnode

Ignition Arc

Solenoids

Nozzles

ControlElectronics

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Summary

• The ORION Lab provides a unique combination of maneuver kinematics and dynamics simulation capabilities.

• ORION enables experimental research in

Spacecraft formation flight, rendezvous and proximity operations

Robotic operations for space debris removal and on-orbit servicing

Autonomous, teleoperated, and hybrid control systems for ground, air and space systems

Guidance, navigation, and control in dynamic and unstructured environments Prediction algorithms and compensation methods for contact dynamics of complex bodies Human-machine interaction in uncertain environments and under time delay

• ORION can quickly be adapted and customized to meet specific project needs

• Short-notice test scheduling and low operating cost

• ORION projects are supported by Florida Tech faculty and graduate students with wide range of expertise and experience

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Contact

Dr. Markus Wilde

Florida Institute of Technology

Department of Aerospace, Physics, and Space Sciences

mwilde@fit.edu

(+1) 321-674-8788

http://floridatech.edu/orion