This presentation provides an overview of the Astrobee free-flying robot, which NASA Ames is currently developing for intravehicular activity (IVA) use inside the International Space Station

Fong, Terry

NASA Technical Reports Server

Terry	  Fong	  
Intelligent	  Robo,cs	  Group	  
NASA	  Ames	  Research	  Center	  
terry.fong@nasa.gov	  
https://ntrs.nasa.gov/search.jsp?R=20150022101 2019-08-31T05:18:16+00:00Z
2 
Robots for Human Exploration 
Motivation 
•  Help maintain human spacecraft 
•  Enhance crew productivity 
•  Perform work before, in support,  
and after humans 
In-Flight Maintenance (IFM) 
•  Must perform IFM to keep spacecraft 
in a safe and habitable configuration 
•  Many IFM tasks are tedious, time-
consuming, repetitive & routine 
•  Many IVA/EVA tasks cannot be done 
using only fixed sensors / actuators 
Unmanned mission phases 
•  Setup spacecraft prior to human 
arrival (e.g., Mars exploration) 
•  Contingency situations (maintain 
vehicle when humans have to leave) 
Inspect & monitor 
•  Provide mobile camera views 
•  Routine surveys and inventory 
•  Check payload status / health   
Routine maintenance 
•  Change air/water filters 
•  Perform water draw/input on ECLSS 
•  Payload adjustment & trouble shooting 
Contingency response 
•  Assess environment after fire event 
•  Assess & repair Leaks/MMOD damage 
•  Power cycle/reboot electrical equipment 
•  Actuate mechanisms (hatches, valves, etc.) 
IN-FLIGHT MAINTENANCE TASKS  
3 
ISS In-Flight Maintenance Statistics 
Corrective/Preventive Maintenance (CM/PM) Crew Time for USOS (through 7/2014) 
Source: ISS On-orbit Logistics Supportability Assessment Report, Aug 2014 
Final Assembly 
770 hours 
= 2 hr/day avg. 
$50M+ crew-time 
Preventive Maint. 
330 hr/yr avg. 
4 
ISS In-Flight Maintenance 
Extra-Vehicular Activity (EVA) 
•  Not enough crew time to do everything 
(only 1 EVA per year) 
•  Crew must always carry out “Big 12” 
contingency EVA’s 
•  Maintain electrical power system 
•  Maintain thermal control system 
•  Worksite prep & tear down requires 
2-3 hr per EVA 
Intra-Vehicular Activity (IVA) 
•  Crew spends a lot of IVA time on 
maintenance (40+ hr/month) 
•  Routine surveys require 12+ hr/month 
•  Air quality, lighting, sound level,  
video safety, etc. 
•  Crew must always carry out 
contingency IVA surveys 
•  Find and repair leaks, combustibles, etc. 
5 
Repetitive and Routine IVA Tasks on ISS 
Camera positioning 
•  Many cameras are used for IVA work 
•  Crew has to manually reposition video 
cameras monitored by mission control 
•  Camera are essential for many tasks 
•  Safety surveys 
•  Equipment and payload inspections 
•  Crew “over the shoulder” views  
during IVA activities 
Logistics 
•  Crew must locate equipment and 
materials needed for IVA work 
•  Crew spends up to 1 hr per day  
manually searching for items 
•  6,000+ “lost” items in ISS Inventory 
•  Automated logistics is a key HEOMD 
priority for ISS and future missions 
6 
Assistive Free-Flyer (AFF) 
What are AFF’s? 
•  Small free-flying robots that 
assist humans  
(Szafir, Mutlu, & Fong 2013) 
•  AFF’s perform exploration, 
surveillance, inspection, 
mapping, transport, etc. 
•  AFF’s are often co-located 
with human and operate in 
human environments 
Key design issues 
•  Autonomy 
•  Ecological fit 
•  Human-robot interaction 
•  Morphology 
•  Navigation 
•  etc. 
7 
SPHERES with Google Nexus S smartphone 
Ground Control User Interface 
Smart SPHERES (2011 - 2014) 
Mobility: SPHERES satellite 
•  IVA free-flyers (NASA / DARPA / MIT) 
•  22 cm diameter, 4 kg 
•  Cold-gas propulsion + AA batteries 
•  External sonar beacon localization 
•  3 units installed on ISS (2006) 
•  52+ test sessions, 340+ hr crew time 
Computing: Google Nexus-S 
•  Android smartphone 
•  1GHz Cortex A8 (ARM) + GPU,  
512 MB RAM, 16 GB flash 
•  3-axis gyro, 3-axis accel.,  
two color cameras 
•  802.11 b/g/n (Wi-Fi) 
•  Robotics software 
•  RAPID middleware 
•  Basic teleop + command sequencing 
•  Ground control user interface 
8 
Smart SPHERES on ISS 
Luca Parmitano working with Smart SPHERES in the ISS Japanese Experiment Module 
9 
IVA Survey with Smart SPHERES 
2x speed 
December 12, 2012 (ISS Japanese Experiment Module) 
Crew: Kevin Ford, Expedition 33 Commander 
2x 
10 
Astrobee IVA Free-Flying Robot 
Overview 
•  Free flying robot for inside the ISS 
•  Astrobee will be used by flight controllers 
for mobile sensing and camera tasks 
•  Astrobee will succeed SPHERES as a 
microgravity robotic testbed 
Automated operations 
•  Automated task execution / notification 
(ground supervisory control) 
•  Autonomous perching & station keeping 
•  Autonomous free-flyer docking / resupply 
Telerobotic sensor platform 
•  6-DOF localization (no beacons): 
structured light (Kinect) + stereo vision 
•  Environment sensors and monitoring 
algorithms (air quality / CO2) 
•  RFID sensor for sparse area inventory 
(key component of automated logistics) 
Open and extensible platform 
•  Expansion port (mechanical, data, & 
power) for new payloads 
•  High-level programming interface 
(protects safety critical functions)  
•  Support microgravity experiments and 
E/PO (robotic competitions) 
11 
Why “Astrobee”? 
TopCoder challenge 
•  Announced at NY ComicCon 
•  818 registrants (record for this type of challenge) 
12 
Point Design (Feb 2015) 
HazCam 
Terminate
 Button 
LED 
Signal Array 
Touch Screen 
SciCam 
Perching 
Arm 
NavCam PerchCam 
DockCam 
Peripheral
 Bay 
Peripheral
 Module 
30 cm 
13 
Point Design (July 2015) 
Perching Arm 
Dock Adapter Avionics 
Centrifugal Fan 
Nozzles 
14 
Dock Design (July 2015) 
Light 
Indicator  
Battery 
Charger  
Power 
Connector 
Switch 
Guard  
On / Off 
Switch  
Ethernet 
Connector  
Lance 
Power / Data 
 Connector  
14” x 30” x 3.25” 
15 
Avionics 
Low-Level Processor (LLP) 
•  Minimal “critical” code 
•  Hard real-time 
•  Motion control, high rate  
sensor processing 
•  Significant code V&V 
Mid-Level Processor (MLP) 
•  Most “core” code 
•  Obstacle detection,  
handrail tracking,  
navigation, arm control 
•  Medium level code V&V 
High-Level Processor (HLP) 
•  On-board interface control 
•  Guest science (payload) code 
LLP 
HLP 
MLP 
Ethernet 
Switch 
USB 2.0 
Hub1 
EPS 
Dock 
Nav_Payload 
VO_Payload 
Arm_Payload 
Payload1 
Payload2 
Payload3 
USB 2.0 
Hub2 
USB 2.0 
Hub3 
16 
Communication 
17 
Control Station Mockup 
18 
Performance Requirements 
Operations 
•  Free-flight throughout US Operating Segment (USOS) 
•  Holonomic motion (instantaneous thrust in any direction) 
•  20-40 cm/s for up to 9 hr “sortie” 
Minimize crew time 
•  Certify for autonomous operations (in USOS) 
•  Auto docking & recharge 
•  Modular design for quick repair 
Avoid pre-defined keepout zones 
•  Module walls, known obstructions, zones near vents  
•  Areas specified by ground operator or crew 
Avoid collision  
•  Detect static and dynamic hazards 
•  Bring robot to stop prior to collision 
Modes 
•  Remote: manual control, supervisory control 
•  On-board: payload control (guest science), auto dock  
19 
Microgravity Research Scenario 
Sequence of Events 
1 
Prior to research activity, ground 
operator loads experimental software, 
free flyer does self-diagnostics. 
2 Free flyer undocks and moves to experimental module. 
3 Astronaut attaches external hardware to free flyer. 
4 Ground operator sets up individual tests, and astronaut initializes tests. 
5 Free flyer perches to wait while astronaut pauses for EPO Event. 
6 Astronaut detaches hardware and then free flyer returns to dock. 
2 1 
4 3 
6 5 
20 
Microgravity Research Timelines 
Perform Research 
Activity
Standby for Crew 
(Perch)
Autonomous Flight to 
Research Location
Autonomous Flight to 
Dock
Standby for Crew 
(Perch)
30 min30 min 30 min60 min 60 min
Low Intensity (6.5 hr) 
High Intensity (3.5 hr) 
Perform Research 
Activity
Standby for Crew 
(Perch)
Autonomous Flight to 
Research Location
Autonomous Flight to 
Dock
Standby for Crew 
(Perch)
30 min30 min 30 min60 min 4 hrs
21 
Microgravity Research Payloads 
Guest science 
•  Researchers can provide arbitrary code 
•  Most guest science code runs in sandbox, uses high-level control API 
•  Peripheral bays and peripheral ports 
Class! Description! Requirement!
Small" Payloads too light to affect mobility"
Host payload and operate in all modes 
with full performance, without tuning 
controls"
Medium"
Typical payload that fits in 
peripheral bay, not too massive 
or unbalanced"
Host payload and operate in all 
modes; reduced performance, some 
testing and controls tuning may be 
needed"
Special" Other payloads" Assess on a case-by-case basis"
22 
Mobile Camera Scenario 
Sequence of Events 
1 
30 mins before crew activity, ground 
operator initializes free flyer. Free flyer 
does self diagnostics and operator 
gives module and perch location. 
2 Free flyer undocks and flies to module. 
3 Free flyer perches to wait for activity. 
4 
During activity, ground operator makes 
adjustments to pan/tilt as astronaut 
moves around. 
5 Ground operator moves to new perch because astronaut is blocking view. 
6 After activity, free flyer returns to dock for charging 
2 1 
4 3 
6 5 
23 
Mobile Camera Timeline 
Flying and Perching (6-9 hr) 
Communication Loss 
•  During LOS, Astrobee continues to hold its position, recording and 
storing video on-board 
•  At AOS, resumes downlinking the live video stream 
Perched Video of 
Astronaut Activity
Standby for Crew 
(Perch)
Autonomous Flight to 
Perch Location
Autonomous Flight to 
Dock
Standby
(Contingency Time)
30 min
30 min
30 min
30 min 3-6 hrs
Perch Change (if 
necessary)
30 min
Interactive Flying 
Videography (Teleop)
30 min
24 
Survey / Search Scenario 
Sequence of Events 
1 
One day in advance of crew activity, ground 
controller activates the free flyer, uploads 
tool ID and expected location, and initiates 
SEARCH function. 
2 
Free flyer undocks and heads to suspected 
location. Free flyer avoids astronauts and 
equipment along the way. 
3 Free flyer scans the expected location with its RFID reader, but the tools is not there. 
4 Free flyer initiates automated search pattern. 
5 Free flyer locates tool at the other side of the module and updates logistics database. 
6 Free flyer returns to dock. 
2 1 
4 3 
6 5 
25 
Survey / Search Timeline 
Environment / Inventory Flights (3 hr) 
Communication Loss 
•  During LOS, continues to operate, recording and storing 
measurements on-board 
•  Transmits completed survey data file on return to dock 
•  Downlinks the RFID and location of found items 
Conduct Survey/Search
Autonomous Flight to 
Initial Survey/Search 
Point
Autonomous Flight to 
Dock
30 min30 min 2 hrs
26 
Astrobee Partners 
Human Exploration Telerobotics 2 project (STMD GCD) 
•  Astrobee core development (NASA Ames and JPL) 
SPHERES program (HEOMD ISS) 
•  Development & test facilities 
•  ISS facility infusion customer 
Logistics Reduction project (HEOMD AES) 
•  RFID Reader (external payload) for Astrobee 
Autonomous Systems Operations project (HEOMD AES) 
•  RFID data management for Astrobee 
2015 SBIR (STMD) 
•  Z5.01 “Payload Technologies for Assistive Free-Flyers” 
•  Awarded 3 Phase 1 projects 
2015 Early Stage Innovation (STMD) 
•  Topic 1: “Payload Technologies for Assistive Free-Flyers” 
•  Mirrors SBIR subtopic, but targets academia (proposals under review) 
27 
Questions? 


Astrobee: A Free-Flying Robot for the International Space Station

Abstract

Similar works

Full text

Available Versions

NASA Technical Reports Server