l JSTS Vol. 23, NO. 2

Launch of OICETS ("KIRARI") on Dnepr launch vehicle

Toshihiko Yamawaki1, Katsuyoshi Arai1

, Ichiro Mase2, Seiji Yoshimoto2

, Jun Nakajima2,

Kenichi Ikebe2, Shunichi Morioka3, Vladislav Solovey4, Olexiy Silkin5, Alexander Svotin4

1 Japan Aerospace Exploration Agency (JAXA) OICETS Project team 2-1-1 Sengen, Tsukuba-shi, lbaragi, 305-8505, Japan

2 Space Systems Division, NEC Corporation 1-10, Nisshin-cho, Fuchu, Tokyo, 183-8501, Japan.

3 NEC Engineering Ltd. In Nakagawara Research Institute 5-22-5, Sumiyoshi-cho, Fuchu, Tokyo, 183-8502, Japan.

4ISC Kosmotras, 5SDO Y uzhnoye

Abstract In August 2005 Japan Aerospace Exploration Agency (JAXA) successfully launched the Optical Inter-orbit Communications Engineering Test Satellite (OICETS) by the Dnepr launch vehicle from the Baikonur Cosmodrome to demonstrate innovative technologies of laser-based optical inter-orbit communications between OICETS and European Space Agency's (ESA) Advanced Relay and Technology Mission Satellite (ARTEMIS). The Dnepr launch vehicle is the rocket which is converted from the SS-18 liquid-fuelled Intercontinental Ballistic Missile (ICBM) and operated together with the launch facility located on the Baikonur Cosmodrome by ISC Kosmotras. This was a challenging task because JAXA had to modify OICETS, which had already been manufactured and tested to be launched by Japanese J-I rocket, to accommodate to the new launch vehicle interface and the change of orbit. JAXA also had to plan the launch campaign at the unfamiliar launch site. All of these works were completed in 13 months, thanks to the dedicated efforts of all the participants. In this paper, experiences gained from coordination works of the launch vehicle interface and the launch campaign in Baikonur are presented.

1. Introduction Communications between geostationary satellite and low earth orbit satellites are the key technologies to support various space activities such as global data reception from earth observation satellites. As compared to conventional communication systems using radio frequencies, optical inter-orbit communication systems have advantages such as smaller equipment size, higher data rate, larger communication capacity, and less interference risk with other communication systems. Japan Aerospace Exploration Agency (JAXA), fonner National Space Development Agency of Japan (NASDA), has been conducting research activities of the laser inter-orbit communication technologies since 1985. The Optical Inter-orbit Communications Engineering Test Satellite (OICETS) program started in 1992. OICETS is the satellite to demonstrate the advantages of the laser inter-orbit communication technologies. As shown Fig. I, OICETS is a three-axis stabilized satellite with a mass of approximately 570kg. It has a box-type main structure which is approximately 0. 78 x 1.1 x I .Sm in dimension. When the solar paddles are fully extended, OICETS is about 9.4 min width. The mission subsystem of OICETS is the Laser Utilizing Communication Equipment (LUCE). LUCE is consisted of two parts, the optical part (LUCE-0) and the electronic part (LUCE-E). LUCE-0 is installed on the anti-earth panel, while LUCE-Eis placed inside the satellite.

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OICETS

Fig. 1 OICETS configuration

OICETS was originally planned to be launched by the Japanese J-1 launch vehicle into the circular orbit with the inclination of 35 degrees from Tanegashima Space Center in JFY2001. However, the OICETS project was frozen for 3 years because of the imperfect launch of ARTEMIS, which resulted in taking one and a half year for ARTEMIS to climb up to the geo-synchronous orbit by its own propulsion system. When the project resumed in 2004, OICETS had to be launched within one year due to some technical reasons, but any Japanese launch vehicle was not available for OICETS by the time limit, the summer of 2005. Therefore, JAXA decided to launch OICETS by the Russian-Ukraine-made Dnepr launch vehicle from the Baikonur Cosmodrome.

2. Dnepr Launch Vehicle Interface The Dnepr launch vehicle (L V) is the rocket which is converted from the SS-18 liquid-fuelled Intercontinental Ballistic Missile (ICBM) and consists of two primary stages and a small post-boost stage. It also has the Space Head Module (SHM) to contain the payloads, which consists of an intermediate section, a payload adapter and the SS-18 standard faring. SHM was attached to the third stage's upper end. In the standard launch sequence Dnepr is steam ejected from the launch canister placed in the underground silo. The first stage propulsion unit is ignited after the ejection. The third stage was equipped with a liquid propellant, two-mode propulsion unit so that spacecraft was separated from the third stage by means of L V's throttled back operation. Fig.2 shows the Dnepr configuration. OICETS was attached to the L V adapter by separation devices in the SHM. The adapter was a welded structure made of aluminum-magnesium alloy. Instead of a clamp ring, four pyro-locks were used for OICETS fastening to the adapter. No specific pushing separation system was required because of the "pulling" scheme utilized by the Upper Stage. An additional structure (adapter ring) was attached to the bottom of the spacecraft for accommodating to the new interface.

little modification of SS-18

i I

.. j. i C·3lJOO -

____ ....,Fru....,nn...., Slandard SS-18

2-nd stage

1-st stage

3 JSTS Vol. 23, NO. 2

Use of Standard SS-18 Silo

Transport and · · · Launch Canister

Silo Launcher

Fig.2 Dnepr Configuration ©1sc Kosmotras

Although the standard Dnepr launch system was designed for cold launch, which means that satellites are powered off during onboard the vehicle, OICETS should be powered on for launch. So Dnepr L V third stage and the control software had to be modified to provide additional umbilical lines, RF links, and the optimal trajectory. JAXA had several coordination meetings and lots of telephone conferences with ISC Kosmotras and SDO Yuzhnoye, which designed and manufactured SS-18 and Dnepr LV. As a result, the following new I/F were added to the launch vehicle.

• Umbilical link between the satellite and its Electrical Ground Support Equipment located in an underground bunker in the vicinity of launch silo

• RF link between the satellite and the Satellite Mission Control Center for commanding the satellite and receiving telemetry during preparation for launch

• Space Head Module Air-Purge System to maintain the required temperature condition for the powered satellite during preparation for launch

• Additional mechanism to disconnect OICETS umbilical connector during satellite separation sequences. Pyros were also used for umbilical disconnect mechanisms.

Inside the adapter the sub-payload INDEX satellite was installed, which was developed by the Institute of Space and Astronautical Science, JAXA. As INDEX was designed for cold launch, there was no electrical interface between the satellite and the launch vehicle. Fig.3 shows the separation sequence. Please be aware of the flight direction.

Faring Separation

2.1 Issues in LV Interface

OICETS Separation

4

Adapter with umbilical disconnect mechanism

Separation

Flight direction

Fig.3 Separation Sequence ©ISC Kosmotras

JSTS

INDEX Separation

Vol. 23, NO. 2

JAX.A selected Dnepr LV because its mechanical environment met OICETS mechanical design. This was finally verified by Dnepr ground test, which was conducted by applying OICETS Mechanical Test Model, INDEX Model and SHM flight hardware. The tests consisted of a fit check, dynamic tests, vibration tests, functional tests, shock tests and static load tests. Fig.4 shows test configurations for the fit-check and vibration tests.

Fig.4 Fit-check and Vibration test at SDO Yuzhnoye ©ISC Kosmotrac;

L V telemetry is transmitted via two RF channels of VHF and UHF bands. The calculated maximum level of emission induced by L V equipments occurred during the launch preparation and spacecraft injection into orbit. In some frequencies, electromagnetic emission exceeded the limit of OICETS component sensitivity.

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It was discussed and agreed that during the launch preparation, UHF band telemetry should be switched off until the time of lift off. On the other hand, VHF band telemetry was kept switched on but connected by an umbilical hardwire to the antenna located outside the silo, so there would be no effect on the spacecraft. During injection, spacecraft's structure was expected to reduce the interference for components inside the spacecraft. The components outside the spacecraft were switched on after the separation. Thus, the possibility of electromagnetic interference was considered very small. The Electric Magnetic Capability (EMC) was tested and proved by using integrated SHM during the OICETS launch campaign at the Assembly, Integration and Test Building (AITB) .

2.2 Satellite and ground systems modification Launching OICETS by Dnepr from Baikonur required OICETS to change the orbit inclination from 35 degree to 97.8 degree. JAXA re-evaluated the OICETS design and adopted minimum changes to satisfy new interface requirements without degrading the well established reliability. Even though, the Attitude and Orbit Control Subsystem (AOCS) software had to be modified to accommodate to, - the change of orbit inclination from 35degree to 97.Sdegree, - and the elimination of the de-spin phase which was required for the J-1 LV with the solid motor. JAXA also performed the full system test to confirm OICETS worked well after 2 and half years of storage.

To perform on orbit ARTEMIS - OICETS experiments, experiment plans made at the OICETS mission control center were sent to JAXA tracking stations and ESA Redu station. Experiment data were transmitted from the ESA Redu station and JAXA tracking stations to the experiment data evaluation system at the OICETS mission control center in Tsukuba. Changing orbit affected visibility and operation time sequences of ground stations and the interfaces between ground stations had also been updated during the period of project freeze. Therefore all the above ground systems were required modifications and retests. All the above works were completed in 10 months. Fig.6 shows the schedule.

.. • Optical lin1<

Each satellite orbit data are stored to the OICETS and ARTEMIS every 24 hours.

•• •• 50Mbps •• •• •• •• 2Mbps •• •• •• •• Ka-band RF link • 4

OICETS . ..:....

,---------------- ------------- ' S-band RF link ESA Redu (Belgium) r

I JAXA : ARTEMIS : Tsukuba Tracking and Control Center (Japan) !

Mission Control Facility :• • i : M"sion ctata I OICETS Operation Control Center I !

Rtol hme dat4 I . . : In-orbit Test Equipment otbit prediction I I : l ! OICETS Mission Control Center l

______________________________ J

Fig.5 On orbit experiment configuration

6

2003 2004 2006

Maintenance

---------

PSR Design ...--------1 Modification/Test 1

SC l Preshipment Test j Modification

Design

JSTS

2007

Launch

PDR CDR

Latmch Base Campaign

fSTMl 6 6.6. LSRR FRR LRR

Launch Vehicle l/F

Ground System modification/Test/Integration

I Rehearsal

Fig.6 Launch Preparation Schedule

Vol. 23, NO. 2

3. Launch Campaign at Baikonur Cosmodrome On June 7, 2005 just after the 50th anniversary of the foundation of Baikonur, OICETS arrived at the Yubileyny Airport in the Baikonur Cosmodrome as shown in Fig. 7.

Fig. 7 Arrival of OICETS at Baikonur

The Baikonur Cosmodrome is the launch complex where Sputnik 1, the world's first artificial satellite was launched. The rocket that lifted Yuri Gagarin was also from Baikonur. The Baikonur Cosmodrome is located in the Republic of Kazakhstan, east of the Aral Sea (63° E and 46° N), in a semi-arid zone. The annual temperature averages to 13 degree Celsius, ranges from minus 40 degree Celsius in winter to plus 45 degree Celsius in summer. On June when we started OICETS launch campaign the thermometer got over 40 degrees Celsius during the day time but it was nice in the morning and in the evening. The season changed rapidly and we even felt cool at the end of August. The OICETS launch campaign was conducted at the Assembly Integration and Test Building (AITB), the Fueling Station in the Site 31 (Fig.8), and the Bunker at the launch facility. The Site 31 was built in 1964 as the second launch facility for the Soyuz launch vehicle, and the AITB is a historical building where many payloads such as for Moon, Mars, and Venus have been integrated. Dnepr L V inside its launch canister is placed and fueled in the underground facility called the silo. The L V is ejected from its canister by steam until it reaches approximately 20 meters above the ground. The first stage propulsion unit is ignited after the L V ejection. The Bunker is also an underground facility

7 JSTS Vol. 23, NO. 2

adjacent to the silo, where we brought in our Ground Support Equipment to provide OICETS with electrical power after the satellite was integrated into L V. Based on our launch site survey, we requested following additional items: • 1 OOV power supply for Ground Support Equipment • Uninterruptible power supply • LAN • Communication lines between Baikonur and Japan • High pressure gas supply and protective barriers for the RCS leak test • Office for the payload team

Fig.8 Site 31 ©ISC Kosmotras

Fig.9 depicts the work flow at the launch site, which is similar to the one we prepared for the Tanegashima Space Center. The major differences were as follows: - the satellite after being fueled at the fueling station returned to the AITB where other activities such

as INDEX battery charging and SHM integration took place, so additional precautions for monitoring hydrazine leakage were required

- As the satellite could not be accessed mechanically after it had been integrated into SHM, pyros to deploy solar paddles had to be installed prior to being moved to the fueling station

Transportation (6/7)

(Japan-BD!konur)

Unpack/Setup @AITB01 (6120)

Electrical Test (6126)

Battery Reconditioning

(7110) I

·--------------·------, \ \ Battery I ! I· I : PerlodlcDI bnttery charge I I after battery reconditioning I L .. __ __;

Fueling @FS(Bl1)

Transportatlon(B/6) (FS-AITB)

GSEPack

Transportatlon(7128) (AITB-Fr)

Flm1I lns1>9ctlon(8/t 1)

Launch (8124)

Pyro lnstaU;ation(7/26)

RC5'2 leak Test (7/1'5)

f

SC/Adapter lntegration(B/12)

SHY"' lntagr.ltlon (8114)

SC Flnal Check (8119)

SHMIL V Integration (8116)

•• AITB :Assembly I lntugratfon end Tell BuUdlng •1 RCS:ReDction Control System FS:Fueling Sll!tion ,. SHM:Spaco Head ModuJe

Fig.9 Work flow at the launch site

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The procedures and equipments for handling and testing OICETS had already been applied in Japan many times, but launch vehicle interfaces such as umbilical lines and RF links were verified at the launch site for the first time. One of the big concerns was fueling OICETS at the launch site. Based on the results of several case studies, JAXA made a contact with a Russian company to fuel OICETS with Japanese hydrazine, which was already proved compatible with the OICETS' Reaction Control system (RCS). Interface tubes, connectors, and new procedures written in Russian and English were prepared for the fueling. Intensive dry runs and rehearsals were performed to complete all the necessary work safely on schedule. Another critical concern was the air-purge system to keep the SHM inside temperature stable during the pre-launch preparation, which includes the checking out of the spacecraft and periodical battery recharging. To satisfy this requirement, the High Pressure Thermal Control System (HPTCS) was introduced to the Dnepr L V for the first time. The HPTCS consists of the high pressure vessel charged with air up to 400kgf/cm2

, pneumatic panels, temperature and pressure sensors, and so on. The system had the capability of supplying air continuously up to 6 hours until 40 minutes before launch. Since the worst case analysis showed battery temperatures might exceed their operational limit, JAXA conducted several rehearsals and measured actual temperature data during the launch vehicle preparation after SHM was installed on the Dnepr. It was concluded through the data that the HPTCS was capable to keep the battery temperature low enough even in case of the full battery charging before launch.

Electrical Test @ AITB Area A

Rehearsal @ Fueling Station

OICETS turnover @AITB KOSMOTRAS office

SHM integration @AITB Area 8 Fig.10 OICETS Launch Campaign

Fig.10 shows some activities of OICETS launch campaign. At the OICETS turnover (upper right), the "Daruma" doll was prepared according to the Japanese traditions and one of its eyes was painted wishing for the successful launch. As shown in Fig.11, the checkout equipment at AITB was connected to the checkout and battery charging equipment at Bunker by LAN and also connected to OICETS by air link for telemetry and commanding. Mission Control Center (MCC) was also established in AITB to coordinate satellite launch configuration set up works with Launch Control Center (LCC) and the satellite tracking and control center at Tsukuba.

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OICETS in DNEPR at launch Silo

......... (- a & commanding AITB e1emetry -1ooorn

Chockout oqulpmcnt al Launch ConltOI Center

4. Conclusions

_,/ Chockout and ballOry

c:tiarglng equipment atfull!ty21 Urnblllcal connectors / •

DMpr LV lrd atago

Fig.11 Pre-launch Preparation Configuration

After numerous changes and adjustments of the satellite, the LV, ground systems within a year, OICETS was finally launched into the planned orbit on August 24, 2005. For the launch campaign, we stayed at the launch site for a long period of time where lifestyle, language and culture were different from Japan. That was one of the big challenges for us because understanding different culture was essential for safe and efficient operations at the launch site. Firstly, language supports were the highest priority requirement to complete numerous tasks properly within a limited time. Russian-English interpreters and Russian-Japanese interpreters worked at the launch site. However, interpreters were understaffed as compared to the number of staff working at the site. Japanese and Russian staff always needed an interpreter every time they discussed an issue. Long discussions were often required to reach a mutual agreement because of differences in language, culture and perception among the staff. Once the staff understood their tasks, things were completed very smoothly in various ways based on their ample experiences in space development, which sometimes surprised us. Breaking language barrier was in any case very important. Secondly, supports and advice from a JAXA's medical doctor and local staff were very helpful when we were staying in Baikonur. Besides conducting launch site surveys several times, JAXA also surveyed living environments in the city of Baikonur with the medical doctor prior to the launch site operation. Through the medical doctor's advice, we were able to learn how to get through in the dessert area and to provide with support services, such as Japanese food services and medical supports, for the staff staying at the launch site. We were also able to learn how to deal with the changes in lifestyle and culture from local staff. Launch site surveys were not enough to gather all the necessary information. Supports from local people definitely helped our stay in Baikonur. With all of these helps, long stays in Baikonur were safe and more comfortable than we expected. As well as supports from local people, enhanced cooperation between Russian, Ukrainian, and Japanese staffs also have led to the successful launch.

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Fig.12 OICETS launch on August 24t, 2005

5. Acknowledgement In spite of numerous difficulties, we were able to achieve a successful launch within a year after resuming the OICETS project in the end of July 2004. The authors would like to thank all the staff of Baikonur Cosmodrome, IHI, IHI Aerospace, Fujitsu, SED, Sorun, Sumitomocorp, and Kokusai Aeromarine, for their contributions to the perfect OICETS launch. Good team works made the achievement possible.

References (I) Toshihiko Yamawaki, Takashi Jono, Morio Toyoshima, et al. "Development of Luce (Laser

Utilizing Communications Equipment) for OICETS", IAFOO.M.2.05

(2) Morio Toyoshima, Shiro Yamakawa, Toshihiko Yamawaki, et al. "Reconfirmation of the Optical Performances of the Laser Communications Terminal Onboard the OICETS Satellite", Acta Astronautica, Vol.55, Issues 3-9, pp.261-269 (2004)

(3) Morio Toyoshima, Shiro Yamakawa, Toshihiko Yamawaki, et al. "Long-term statistics of the laser beam propagation in an optical ground-to-geostationary satellite communication link", IEEE trans. on Antennas and Propagation, Vol.53, No.2, pp.842-850, February (2005)