Introduction

The David Florida Laboratory (DFL) is Canada's world-class spacecraft assembly, integration and testing centre, maintained and operated by the Canadian Space Agency. On a fee-for-service basis, the DFL supplies governments and industry with the specialized rooms, equipment and support personnel necessary to assemble and check the spaceworthiness of entire spacecraft, their subsystems, and major components. The facility includes capabilities for thermal vacuum/thermal balance, vibration/modal, and radio frequency testing, as well as mass properties measurements. The laboratory is one of only a few facilities of its kind in the world, capable of simulating the enormous stresses and temperature extremes associated with rocket launch and space flight.

1. Who is David Florida?

C. David Florida was one of Canada's foremost pioneers in space research. Dr. Florida was director of the Canadian National Space Telecommunications Laboratory and manager of the International Satellites for Ionospheric Studies (ISIS) program. In addition, just prior to his death in 1971, he was selected manager of the CommunicationsTechnology Satellite (CTS) or HERMES program.

2. When was the DFL built?

The official opening of the DFL was September 29, 1972.

3. Where is the DFL located?

The DFL is located in Shirley Bay, just west of Ottawa. The lab is located on a site shared by two other government departments, Industry Canada (Communications Research Centre) and the Department of National Defence (DREO).

4. What was the first satellite program tested at the DFL?

The first satellite to be tested at the DFL was the joint Canada-US Communications Technology Satellite (CTS) or HERMES, which was launched in January, 1976. For the HERMES program, the DFL only had the capability to perform component or subsystem level testing. All-up spacecraft testing was performed in the U.S.

5. What was the next major space program supported by the DFL?

The next major space program supported by the DFL was Canada's contribution to the U.S. Space Shuttle program, the remote manipulator system or CANADARM. CANADARM testing began in 1977 and continues through to today. CANADARM components (wrist, shoulder and elbow joint subsystems, the end effector and numerous black boxes) were subjected to a battery of environmental tests that included thermal vacuum, vibration, and electromagnetic compatibility at both the acceptance and qualification levels.

6. In what year was the DFL first expanded?

The DFL's first expansion took place in FY 1979/80.

7. Why was the DFL first expanded?

This first expansion was undertaken as part of a new government policy which aimed at developing first class facilities in Canada wherein to design, build and test full satellite systems.

8. What form did this expansion take?

This first expansion included the addition of a new highbay integration and storage area, and included the procurement of a new large thermal vacuum chamber, a new vibration shaker, and a new large anechoic chamber. The expansion provided the DFL with the capability to perform integration and environmental testing on the new generation of satellites designed for launch aboard the U.S. Shuttle or by European or American expendable launchers.

9. What was the first satellite program tested at the DFL following this first major facility upgrade?

Immediately following the certification of the laboratory, these new facilities were put to use for partial integration and environmental testing of the ANIK-C2 satellite, but it wasn't until the ANIK-D program that the new facilities were really put to the test. Both the ANIK-D1 and D2 satellites underwent full-up environmental testing at the facility over a period of approximately two years. Since that time, the DFL has supported the environmental testing of all of Canada's major satellite programs including ANIK-E, MSAT and RADARSAT.

10. What offshore satellite programs have gone through the facility?

The DFL played a key role in Spar Aerospace landing its first international prime contract for a communications satellite system. The contract called for the design, building and testing of two communications satellites plus associated ground support equipment for Brazil. BRASILSAT S1 and S2 were fully integrated and environmentally tested at the DFL. The DFL was also chosen for the final assembly and the majority of the environmental testing of the European Space Agency's Large Satellite Program, OLYMPUS. Because OLYMPUS was a novel satellite, (i.e., the first design of its kind in the world), it required that in addition to the flight model spacecraft, two qualification models be tested, a structural and a thermal model. Testing of the structural and thermal models began in 1985 and flight model testing in 1987. The spacecraft was finally launched in 1989.

11. What special preparations were required to support OLYMPUS testing?

To properly accommodate this new generation of larger satellites, the DFL was expanded through the addition of a new Bay #3, highbay integration and storage area. This new highbay was twice the size of the existing assembly rooms, measuring some 1,100 m². In addition, upgrades to the facility were also effected in the areas of analytic services, mass properties measurements, infrared testing, and modal analysis.

12. What was the most recent satellite program tested at the DFL?

The DFL just recently completed the integration and environmental testing of the INDOSTAR satellite built by Orbital Sciences for PT MediaCitra, Indonesia.

13. What current and future programs are slated for environmental testing at the DFL?

All of Canada's major space programs are expected to be environmentally tested at the DFL. These include the Mobile Servicing System (MSS) and Special Purpose Dextrous Manipulator (SPDM) Canada's contribution to the International Space Station Program and RADARSAT II. In addition, several foreign programs are also currently under negotiation.

14. What is thermal vacuum testing?

Thermal vacuum or space simulation testing refers to the technique used for simulating or replicating the extreme temperature excursions and vacuum conditions of deep space. This is achieved using a pressure vessel outfitted with thermal shrouds and a vacuum system. The shroud is flooded with liquid nitrogen to achieve the cold side temperatures; alternately, spacecraft heating can be achieved using a series of infrared lamps. The air within the chamber is evacuated first using a conventional mechanical pumping system and then switching to a diffusion or cryogenic system to create the vacuum necessary for space simulation.

15. What kind of temperatures can be achieved within the thermal vacuum chamber? What kind of pressures?

Temperatures within a thermal vacuum chamber normally range between -186°C and +150°C, more extreme temperatures can be achieved in thermal only chambers. Chamber pressures can vary significantly depending on types of systems being used. At the DFL, chamber pressures of 10^-7 torr can readily be attained.

16. Why is vibration testing important?

During launch, the satellite, whether launched aboard an expendable rocket or on the U.S. space shuttle, is subjected to enormous vibrational stresses. As such, it is critical to ensure that the satellite is able to withstand rocket engine vibrations and the gravity multiplying effects of extreme acceleration experienced during a launch.

17. What is an anechoic chamber?

Anechoic, by definition, means having a very low degree of reverberation. An anechoic chamber therefore, is a chamber that minimizes the amount of reflection or reverberation of many different kinds of waves, including radio frequency and microwaves.

18. How does an anechoic chamber work?

An anechoic chamber works by "absorbing" extraneous microwaves. The walls of the anechoic chambers at the DFL are lined with a pyramidal microwave absorber composed of a foam sponge material impregnated with carbon and graphite particles. Any extraneous energy coming into contact with this absorber material is changed into heat which is then dissipated along the absorber itself preventing it from "bouncing" back on to the test article.

19. Why is spacecraft level radio frequency testing performed in an anechoic chamber?

The objective of spacecraft level radio frequency testing is to minimize the amount of reflection back to the spacecraft. The attempt is to try and create an environment similar to that in which the satellite will be operating in space.

20. Besides thermal vacuum, vibration, and radio frequency testing, what other types of environmental testing can a satellite be expected to undergo during a spacecraft level program?

Additional spacecraft level testing consists primarily of mass properties measurements, ambient deployment tests, and acoustic testing. The DFL's vertical axis measurement system (VAMS) is used to perform mass properies measurements that include moment of inertia, product of inertia, centre of gravity, and mass. Ambient deployment tests of the various spacecraft appendages are performed primarily in DFL's highbay #3. The DFL has access to a number of different types of deployment rigs and fixtures for performing these delicate tasks. Finally, acoustic testing: although the facilities for reproducing the effect of acoustically induced vibration in spacecraft structures does not exist within the DFL proper, the DFL has ready access to and assists in the conduct of these tests at the National Research Council of Canada's Aeroacoustic Test Facility.

21. How many Canadian companies and organizations have utilized the services and facilities available through the DFL?

Over the years, more than 243 Canadian companies and organizations have availed themselves of the services and facilities of the DFL. This includes some thirty-five different companies and seventy-five different programs in the last year alone. Although many of these users are repeat customers, the DFL's client list continues to grow on an annual basis.