Figure 7-4: EPM+, stowed into LV fairing, dimensions

VEnUS: Vega Electric Upper Stage

Davide A. Nicolini Vega Operational Launch System Project Manager

Extension of Vega capabilities using an EP module

•  VEnUS is a 12kW Solar Electric Propulsion tug, an additional orbital transfer kit installed on the launch vehicle payload interface, to enable new mission types (MEO, GEO, interplanetary) enlarging the Vega market base and developing new services as debris or failed satellites removal.

•  VEnUS extends VEGA mission capability to orbits beyond LEO:

!  Medium Earth Orbits !  Geosynchronous Earth Orbit !  Highly Elliptic Earth Orbits

!  Lagrange Points Halo Orbits

Extension of Vega capabilities using an EP module

•  ESA is running phase A with Compagnia Generale per lo Spazio (OHB-CGS) on the autonomous orbit raising module based mostly on off-the-shelf hardware and powered by electric thrusters.

•  A clear business case exists for European interplanetary

missions like Proba-3 or MEO class satellite constellation replenishment missions (as Galileo or O3b) bringing them within reach even using the current Vega launcher design.

Opens Vega to new class of missions currently out of reach

High-powered SEP Enables Multiple Applications

3

ISS)U5liza5on)

Payload)Delivery))

Commercial)Space)Applica5ons)

Satellite)Servicing)

Orbital)Debris)Removal)

Deep)Space)Human)Explora5on)

Solar)Electric)Propulsion))

Space)Science)Missions)

OGA)Missions)

Picture taken from NASA website

Missions within reach

Orbit Orbital elements Application Vega release

orbit VENUS

Dry mass Prop. mass

P/L mass

Mission time

MEO h = 8062km i = 0 deg ; e = 0 O3b h = 300 km

i = 5.2 deg ; e = 0 681 kg 421 kg 1467 kg 7.6 mo

MEO h = 23222 km i = 56 deg; e = 0 GALILEO h = 300 km

i = 5.2 deg ; e = 0 681 kg 535 kg 1048 kg 7.7 mo

GEO h = 35786 km i = 0 deg; e = 0

Telecom, Data, Services

h = 860 km i = 5.2 deg ; e = 0 681 kg 551 kg 944 kg 8.7 mo

Sun-Earth L1 d = 1.491.110 km Scientific h = 300 km i = 5.2 deg ; e = 0

786 kg * Additional tanks 919 kg 834 kg 19.4 mo

Earth-Moon L1 d = 326.370 km Scientific, Communications, Infrastructure

h = 300 km i = 5.2 deg ; e = 0

786 kg * Additional tanks

847 kg 907 kg 18 mo

NEA d = 2.047.990 km Scientific h = 300 km i = 5.2 deg ; e = 0

786 kg * Additional tanks

935 kg 819 kg 19.8 mo

Active debris removal/towing

h = 23222 km i = 50 deg; e = 0

GALILEO FOC 01 & 02 re-orbit

h = 300 km i = 50 deg ; e = 0

981 kg ** docking system 490 kg N/A 18 mo

SEP - Enabling propulsion technology

SEP can enable high delta-V missions (�V > 2.0 km/s)

681,2 595,3

534,4

1616,0

78,0

78,0

1049,4

53,7

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Electric4Propulsion4Module Chemical44Propulsion4Module

Mass$[kg] Available4Satell ite4mass

LV4P/L4Adapter

Propellant

Module4dry4mass4w/4margin

SEP v s . CPS pe r f o rmance comparison: generic 4.0 km/s DV orbit raising mission, launched by VEGA-C

786,2 718,1

230,0 210,0

847,0

547,0 1455,01215,0

78,0

78,0

78,0

78,0

906,8

1274,9 525,0

485,0

0

500

1000

1500

2000

2500

3000

ElectricPropulsion

Module;+;(HET)

ElectricPropulsion

Module;+;(GIT)

LISAFPathfinderVEGA;C

LISAFPathfinderVEGA

Mass$[kg]

Available;Satell ite;mass

LV;P/L;Adapter

Propellant

Module;dry;mass;w/;margin

SEP v s . CPS pe r f o rmance comparison: LISA Pathfinder mission (S/E L1 Lagrange Point)

Payload volume allocation

LAUNCH SYSTEM / SPACECRAFT INTERFACES CONTROL FILE CHAPTER 3

LISA Pathfinder VG-DCI-1/50700-AE

Page : 15

Issue : 1

Rev. : 2

This document contains export controlled information that may not be reexported outside of ARIANESPACE and authorized subcontractors or licensees � ARIANESPACE

3.6.2 SPACECRAFT INSIDE USABLE VOLUME (FAIRING DYNAMIC ENVELOPE)

Subject to RfW-01

Vega LPF CPS Module Vega VEnUS SEP Module

Deployed and stowed configuration

Solar Array Technology Development

MegaFlex Engineering Development Unit (EDU) employs an innovative spar hinge to reduce stowed volume. Alliant Technical Systems (ATK)

ROSA Engineering Development Unit (EDU) employs an innovative stored strain energy deployment to reduce the number of mechanisms and parts. Deployable Space Systems (DSS)

Module design summary

•  Solar Propulsion Sub-system: –  Four COPV 133 l gas tanks

–  Two gimballed HET, 5 kW class (Hot redundancy) –  Two Xe Resistojet triads (for attitude control, no reaction wheel included) –  One PPU per thruster –  High pressure inlet Xe Flow Controller (piezo proportional valve based)

•  Power generation –  Flexible Solar Panels (US single source), enabling technology to allow panels

stowage –  17.5m2, Ø 5m, ~30 kg per wing –  12.5 kW BoL, ~30% power degradation at EoL –  “Blow-down” power management logic aimed to minimize SA over-dimensioning,

when accounting for the space radiation driven solar cell degradation: PPU input varies from 5kW BoL to 3kW EoL, with decreasing thrust and constant Isp

•  Complete set of S/S for full autonomous nominal operations –  ACS sensing, OBDH, PCDU, TMTC, TCS, SADM, Sat Release Mech

Components layout

Proba-3 case

•  Among currently planned ESA missions, PROBA3 fits the definition of VENUS class of missions:

!  Small scientific spacecraft " 540 kg launch mass !  High Elliptic Earth Orbit " a=36943 km, hp=600 km, ha=60530 km,

e=0.811114, i=59°, w=188° !  Target launch date is compatible with VENUS development schedule (2019)

Development compatible with Vega-C qualification flight

Phase Milestone Duration Start End

Phase A KO - 03/2014 03/2014

Preliminary feasibility study 9 mo 03/2014 12/2014

PRR 3mo 02/2015 05/2015

Phase B SRR 3mo 05/2015 07/2015

PDR 7 mo 07/2015 02/2016

Phase C SDR 10 mo 04/2016 01/2017

CDR 10 mo 01/2017 10/2017

Phase D GQR 10 mo 10/2017 07/2018

Phase E1 Launch Campaign (VEGA-C maiden flight)

2 mo 07/2018 09/2018

FQR 3 mo 05/2019 08/2019

• ESA currently plans to continue in the 2015/2016 period the VEnUS design up to completion of phase B

Summary and way forward

•  Overall the technologies required have now reached the required TRL and offer opportunities for Vega to take position on new space services and missions

•  Flexibility is a key feature: designed so its building blocks can be used as SEP tug, SEP spacecraft platform or SEP propulsion module

•  Initial design driven by a Galileo-type mission (most dimensioning) being a clear business case, but its performance can meet farer orbits as GEO using the module as S/C bus or as interplanetary mission (e.g. transfer to Lagrange point orbits of scientific S/C like Proba-3)

•  The EP module shall be designed with a low-cost approach, by making use of existing COTS H/W as much as possible, in order to reduce recurrent costs reducing the impact on the Vega launch service price

!  CBE cost and target: 10% of launch service cost !  Competitive to Soyuz launched from Kourou