Astrobee Communication Design Overview - PowerPoint Presentation

Slide1

Astrobee

Communication Design Overview

Slide2

Agenda

Astrobee Overview

Communications Overview

Communications Data FlowVideo Distribution PolicyGround Data System (GDS) Requirements for Astrobee Payloads Communications Hardware

2

Slide3

Astrobee

Overview

Three free flyers on ISS starting spring 2019

Docking station for recharge and wired communication Built in perching arm using payload interface 6 total cameras for various purposes, including one cellphone class HD camera.

Main purposes:

Host guest science payload (GSP payloads)

Serve as mobile camera for ISS situational awareness

Serve as mobile sensor platform

First GSP Payloads

REALM RFID reader

Zero Robotics High School and Middle School competitions

Slide4

Current Robot Design

FORWARD

12.5 x 12.5 x 12.5 inches

10.5 kg (with arm + 4 batteries)

Slide5

Astrobee

5

Slide6

Computing

Core Avionics Stack

Perching Arm Controller

Propulsion Module Controller

AFT/CUTAWAY VIEW

Slide7

Command and Data Handling

Design Drivers

Reliability: Multi-processor isolation, serviceable, upgradeable

Power-efficient high performance for machine vision, HD videoSupport a variety of data busesDesignHybrid COTS/custom approach: Integrated COTS modules on custom carrier boardsPower-efficient ARM processors (embedded variants of cell phone technology)Three independent processorsTop two boards accessible for crew replacement or upgrade

Mid-Level + High-Level Processor

Low-Level Processor

Backplane

EPS

Connector

Slide8

Selected CDH Architecture

Three ARM processors to isolate guest code, vision based navigation and 62.5 Hz control loop

Low Level Processor

(LLP) – Linux, Dual coreRuns high freq. EKF and propulsion control loopMid Level Processor (MLP) – Linux, Quad coreRuns absolute localization algorithms, obstacle detection, sequencer, communicationsHeavy processing power used by visionHigh Level Processor (HLP) – Android, Quad coreInterface with Science Camera and Display

Encodes video with dedicated hardware

Runs guest science code

Slide9

Agenda

Communications Overview

9

Slide10

Communications Overview

Design Drivers

Reliability: Degrade gracefully with unreliable comms

Live HD video and telemetryDownlink full logs after sortieInter-robot commsDesignLive comms through JSL WiFi / Ku-band / TReKTelemetry using DDS protocolHard-wired Ethernet downlink through dock

Slide11

Queen

Honey

Bumble

JSC

System Data Flow Diagram

Ethernet/LAN

WiFi

:

Payload LAN

Ethernet: Internal IP

Ethernet: Internal and Payload LAN

ISS

LLP

MLP

NAS

Ku-Band

ARC MMOC

White Sands

Operator Control (MCC)

Operator/Engineer Control

Crew Control Station

Storage

HLP

Payload

Dock

JSL

Payload LAN

Payload LAN Switch

5GHzWAP

Other/LAN

Link Legend

USB

Internal

Switch

Internal

Switch

Dock CPU

11

Payload PD

Operator Control

Big Screen (MCC)

Bldg-8

MSFC

Operator Control

(POIC)

Big Screen (POIC)

Ground Relay (HOSC)

NASA TV Public

Future Capability

Slide12

Network Description (1/2)

All processors inside

Astrobee

are on a private network, connected via an internal 100Mbit switch.All internal processors have an internal IP address that is not routed outside of Astrobee.Internal IP addresses are used for internal FSW communications.MLP WiFi is used for telemetry and commanding to GDS. HLP WiFi is enabled and used for .

Redundant interface to access the

freeflyer

if the MLP interface dies.

Streaming HD video to the ground.

Possible use is for Guest Science.

Payloads interface via USB to the HLP

Should they use a USB-to-Ethernet solution, they are isolated from the rest of the network.

The

WiFi

modules associate with the JSL

PayloadLAN

WAPs, which also route to the ground via KU-band over JSL-2 to MSFC.

Slide13

Network Description (2/2)

There is a 100Mbit switch inside the Dock, which serves both the docked

Astrobees

and the Dock CPU.The dock will connect to a 100Mbit ISS Router, which can flow down to the ground via KU-band over JSL-2 to MSFC.The Dock CPU will have both an internal Astrobee and a PayloadLAN IP address.The Dock CPU aids in software updates and waking up hibernating Astrobees.We are relying on KU-IP-Services to route data to the ground over an IP-network built on the CCSDS foundation of KU-band.

P4 Design Review

Slide14

Ground Data Relay

For conserving bandwidth, only one stream of data & video will flow to the ground per robot. Data is relayed to multiple ground stations via a “relay” at MSFC HOSC.

A computer at the HOSC routes DDS and streaming video traffic from ISS KUIP to interested ground nodes.

It will use COTS software, with custom configuration files. The configuration files will be under version control at Ames. The DDS data relay has been tested at Ames.

Slide15

Data Paths Overview

All data paths to the ground make use of KU-IP Services and

TReK

.TReK HPEG: Allows us to control our payload outside of the HOSC via “proxy” IP addresses.TReK CFDP: File delivery protocol based on CCSDS.

Slide16

Agenda

Communications Data Flow

16

Slide17

ARC-MMOC

ISS

Astrobee3

Astrobee2

Astrobee1

MLP

(Ubuntu)

x.x.x.x

(static)

ICU

Ku-Fwd G/W

HOSC/POIC

Magic

TReK Toolkit

CFDP

Ku-Fwd

Auth

Svr

SSH/SCP

TCP: 22

HPEHG

Ku-Fwd G/W

DDS

UDP Port: N1-N2

LLP

(Ubuntu)

HLP

(

Andriod

)

RTSP

TCP: xx UDP: P1-P2

Internal Switch

ELC

Crew Control Station GUI

DDS

RTSP

Astrobee Dock

Ground Computer (WS4)

Internal Switch

CPU

(Ubuntu)

WAP

VPN Server

Public Internet

VPN Software

Payload PD

Flight Configuration for Astrobee

Astrobee Relay

(

RedHat

)

DDS-

Srvr

UDP Port: N1-N2

RTSP-

Srvr

TCP: xx UDP: P1-P2

TReK

CFDP

Ground Control Station GUI

DDS

RTSP

Ground Computer

VPN Software

Ground Control Station GUI

DDS

RTSP

JSC Bldg-8

Ground Computer

VPN Software

VLC

RTSP

TReK

HPEG

(

GroundNode

2)

Payload WAN/ISS Ethernet

Ku-Forward

TReK

HPEG

(

GroundNode

1)

Putty

SSH

TReK

HPEG

-

AstroBee

(1-3)_wireless(1-2)

- NAS

- ASTROBEE_DOCK

Each 1-to-1 NAT:

-

SpaceNode

-ID (Static)

- X.X.X.X (Dynamic per session)

Slide18

ARC-MMOC

Ames-Granite-Lab “ISS”

Astrobee3

Astrobee2

Astrobee1

MLP

(Ubuntu)

x.x.x.x

(static)

Payload WAN/ISS Ethernet

HOSC/POIC

TReK Toolkit

CFDP

Ku-Fwd

Auth

Svr

SSH/SCP

TCP: 22

HPEHG

Ku-Fwd G/W

DDS

UDP Port: N1-N2

LLP

(Ubuntu)

HLP

(

Andriod

)

RTSP

TCP: xx UDP: P1-P2

Internal Switch

ELC

Crew Control Station GUI

DDS

RTSP

Astrobee Dock

Ground Computer (WS4)

Internal Switch

CPU

(Ubuntu)

WAP

VPN Server

Public Internet

VPN Software

PRCU Test Configuration for Astrobee

Astrobee Relay

(

RedHat

)

DDS-

Svr

UDP Port: N1-N2

RTSP-

Svr

TCP: xx UDP: P1-P2

PRCU/RAPTR

Ground Control Station GUI

DDS

RTSP

TReK

HPEG

(

GroundNode

2)

HOSC

Router

TReK

HPEG

(

GroundNode

1)

Putty

SSH

TReK

HPEG

-

AstroBee

(1-3)_wireless(1-2)

- NAS

- ASTROBEE_DOCK

Each 1-to-1 NAT:

-

SpaceNode

-ID (Static)

- X.X.X.X (Dynamic per session)

Slide19

ISS

Astrobee1

MLP

(Ubuntu)

x.x.x.x

(static)

TReK Toolkit

CFDP

SSH/SCP

TCP: 22

DDS

UDP Port: N1-N2

LLP

(Ubuntu)

HLP

(

Andriod

)

RTSP

TCP: xx UDP: P1-P2

Internal Switch

Astrobee Dock

Internal Switch

CPU

(Ubuntu)

WAP

Test Configuration

A

Payload WAN/ISS Ethernet

Dev Laptop (

Macbook

)

Slide20

ARC-MMOC

ISS

Astrobee1

MLP

(Ubuntu)

x.x.x.x

(static)

ICU

Ku-Fwd G/W

HOSC/POIC

Magic

TReK Toolkit

CFDP

Ku-Fwd

Auth

Svr

SSH/SCP

TCP: 22

HPEHG

Ku-Fwd G/W

DDS

UDP Port: N1-N2

LLP

(Ubuntu)

HLP

(

Andriod

)

RTSP

TCP: xx UDP: P1-P2

Internal Switch

Astrobee Dock

Ground Computer (WS4)

Internal Switch

CPU

(Ubuntu)

WAP

VPN Server

Public Internet

VPN Software

Test Configuration

B

TReK

HPEG

(

GroundNode

1)

Ground Control Station GUI

DDS

RTSP

Putty

SSH

Payload WAN/ISS Ethernet

Dev Laptop (

Macbook

)

TReK

HPEG

-

AstroBee

(1-3)_wireless(1-2)

- NAS

- ASTROBEE_DOCK

Each 1-to-1 NAT:

-

SpaceNode

-ID (Static)

- X.X.X.X (Dynamic per session)

Ku-Forward

Slide21

ARC-MMOC

ISS

Astrobee1

MLP

(Ubuntu)

x.x.x.x

(static)

ICU

Ku-Fwd G/W

HOSC/POIC

Magic

TReK Toolkit

CFDP

Ku-Fwd

Auth

Svr

SSH/SCP

TCP: 22

HPEHG

Ku-Fwd G/W

DDS

UDP Port: N1-N2

LLP

(Ubuntu)

HLP

(

Andriod

)

RTSP

TCP: xx UDP: P1-P2

Internal Switch

Dev Laptop (

Macbook

)

Astrobee Dock

Ground Computer (WS4)

Internal Switch

CPU

(Ubuntu)

WAP

VPN Server

Public Internet

VPN Software

Test Configuration

C

Astrobee Relay

(

RedHat

)

DDS-

Srvr

UDP Port: N1-N2

RTSP-

Srvr

TCP: xx UDP: P1-P2

Ground Control Station GUI

DDS

RTSP

Putty

SSH

TReK

HPEG

(

GroundNode

2)

Payload WAN/ISS Ethernet

Ku-Forward

Slide22

Data Path: Telemetry & Video

Telemetry and commands flow through DDS over UDP/IP

With tuned

QoS settings, should avoid traffic spikes after LOS.Sci-cam (Science Cam HD Video) flows through RTSP over UDP/IPRTSP is designed to account for packet loss, thus LOS should be tolerated.Both Video and Data flow through a ground “relay” to de-duplicate traffic to multiple ground control stations observing/commanding Astrobee.

Slide23

Video Multicasting

Video is only downlinked once from the ISS to MSFC, from there it is “

multicasted

” (in reality, multiple unicast streams) to multiple control stations.Video destined for public consumption is pre-screened through Building 8 before being broadcast to various audiences.

Slide24

Data Path: Engineering Tools

SSH capabilities will be in place. Using this, any engineering tools written as part of FSW may be remotely executed.

SSH is enabled on both wired and wireless interfaces on the MLP.

This allows us to jump through the dock in the case that the MLP/HLP are having issues to get to the LLP.

Slide25

Data Flow: SW Updates, etc

From JSL requirements: all SW updates must be made over a secure channel.

SCP/SFTP satisfies this requirement.

Guest Science code may also fall under this as well.(Additional verification methods may be used by FSW, such as checksums, code signing, etc)Two possible paths:Direct to Astrobee over SSH-based protocols.Upload to the Dock CPU and accessed by Astrobee.

This is more useful for multi-

Astrobee

updates.

Slide26

Data Flow: Data Products

Immediate Data Products

High-value logs and telemetry that are requested.

Use CFDP over DTNTReK CFDP tool will be usedDelayed Data ProductsOther wanted or very large productsCopy to NAS, wait for data through existing services (Qsync)

Slide27

Point of Control

TReK

CFDP over DTN Diagram

HOSC

ISS

ISS DTN Gateway

MLP

Ethernet

Switch

Dock

Node 2 Edge Router

Ground DTN Gateway

TReK

CFDP

Ground Routers

Slide28

TReK

CFDP over DTN Setup

TReK

CFDP over DTN is a reliable file transfer protocol using DTN’s bundle protocol to handle periods of LOS.Data is sent serially through each node.The KU Forward connection is between the DTN gateways.Data is stored at the DTN nodes/gateways during a LOS.

MLP

ISS DTN Gateway

Ground DTN Gateway

TReK

CFDP

P4 Design Review

Slide29

Expected Transfer Rates

P4 Design Review

The on-board Dock/Astrobee wired hardware supports 100Mbps. 

The on-board

wifi

utilizes the 11b/g/n standard which can have an average 54

Mbps

 rate 

The Astrobee ISS PIA (Payload Integration Agreement) documents a requested real-time downlink rate to the ground of 15Mbps.

Downlink rate’s are requested on a per-activity basis in the PARD (an Ops Planning data product) 

Current estimates for what Astrobee might need: (Still preliminary and needs testing/measurement)  

1 to 2

Mbps

datarate

 for commanding (all

Astrobee’s

included)

This is by-directional. It is significantly more weighted on the downlink side

We suspect that the standard 0.1

Mbps

uplink rate is sufficient, but more testing is needed

2

Mbps

per HD video stream downlink (so 6Mbps total if operating there Astrobee’s with 1-sci-cam each) (margin should be added plus commanding rate)

Slide30

Per a KUIP subject matter expert:

The average latency is 600

ms.

 This latency impacts TCP based protocols in greater proportion than UDP protocols. The total available uplink date rate for all payloads is 8Mbps. (All of Station has a 20Mbps uplink rate)Uplink of large files should be prescheduled. TReK

CFDP uses UDP

Other payloads have observed up to 30Mbps file downlink rates 

Based on payload specific Blank-book documentation, the HOSC does specify downlink rate caps on-board ISS (Likely on the PEHG). It does incorporate overhead spikes, so higher than 15Mbps might be observed. 

On 11/19/2018, during PRCU testing, we observed a range of 30 - 600 KB/s (4.5Mbps) uplink rate using

Rsync

from the DDS Server to an Astrobee in the Granite Lab.

On 02/15/2019, during the ISS Astrobee Dock Install activity, these

scp

file transfer rates (on average) were observed:

10KB/s uplink, 120KB/s downlink

Expected Transfer Rates

Slide31

Agenda

Video Distribution Policy

31

Slide32

Video Distribution Policy

Video distributed to any Astrobee Ground Control Station will not be recorded or re-distributed

Connecting an Astrobee Ground Control Station to ISS will require authentication with the HOSC network as an ISS Payload Developer (PD)

With the one exception of real-time video to the Astrobee Ground Control Stations, all video generated by Astrobee’s built-in cameras will be reviewed by Bldg-8 before distributing to Non-NASA organizations (including Payload PD’s)A process will be setup where the NASA-Ames Astrobee Facility makes downlinked video available for Bldg-8 review

32

Slide33

Data Path: Video/Data Distribution 1/2

Slide34

JSC MCC

MSFC POIC

Big Screen

Control Station

Big Screen

Control Station

Payload PD

Aud

Control Station

ARC MMOC

Med Screen

Control Station

JSC

Bldg

8

MSFC HOSC

ISS ICU

Live Video

Distributed Video

Full Real-time Stream

MPEG2

KUIP

Data Path: Video/Data Distribution 2/2

Box

Future Work

Slide35

Slide36

Agenda

Ground Data System (GDS) Requirements for Astrobee Payloads

36

Slide37

Ground Payload Computer Requirements

Windows 10

Browser support for HOSC EHS & OSTPV tools

IVODSHeadset connectivity Astrobee Ground Control StationHOSC VPN clientVLC 37

Slide38

GDS required Accounts & Authentications

HOSC HOPS Account for:

IVODS

HOSC VPN loginNASA NDC credential for accessing Astrobee Facility file server for post-ops data downlink38

Slide39

Agenda

Communications Hardware

39

Slide40

WiFi Antenna

2.4 GHz/5.8 GHz

Wifi

antenna~3dBi/5dBi gainOmnidirectionalAdhesive tape mountingAdditional tape will be applied to ensure launch survivalPaper thinMass: 0.477g

P4 Design Review

Slide41

Antenna Placement

Two antennas for each the HLP and the MLP will be placed on

Astrobee

.One antenna will be placed on the front and the back for each processor.This should help with signal strength, no matter what orientation Astrobee is in.The antennas are placed behind the plastic bezel, but outside the metal avionics box.

Slide42

Antennas

PWR

wake

Antenna Placement - Front

Slide43

Antennas are on backside of Dock Adapter

Antenna location

Antenna Placement - Aft

Low adsorbent

filler

Slide44

Antenna Modularity

An SMA/U.FL adapter has been added to ease installation and replacement.

This adapter is in-line.