Form 9.B Project Summary



Proposal Number:


Project Title:

Ultralightweight, Compact, Thermally

Stable, SiC, Snap-Together Microwave


Technical Abstract (Limit 200 words)

A need exists to reduce the weight, size, power

requirements, and cost associated with next

generation, space-based microwave sensors. Trad-

itional optical materials, such as aluminum or glass,

are severely limited in their capability to be

lightweighted. More exotic mater- ials, i.e.

Beryllium, can be used to produce very lightweight

sensor structures but at a very high cost. SSG

proposes the application of Reaction Bonded

(RBO) Silicon Carbide (SiC), and an innovative

Con- tinuous Fiber Reinforced Ceramic (CFRC)

SiC composite as ultralight- weight, thermally

stable, low-cost materials for these applications.

The two materials will be used in an innovative

snap-together design to facilitate

assembly/alignment, and offer significant cost

savings. The Microwave Instrument for the

Rosetta Orbiter (MIRO) currently uses aluminum

as a baseline sensor material; the use of the SiC

materials would reduce the weight associated with

the MIRO instrument by a factor of 2x-4x. The two

proposed forms of SiC have the same coeff- icient

of thermal expansion and excellent thermal

stability. These properties will support a passively

athermalized instrument concept able to withstand

severe thermal environments ranging from

cryogenic to 800°C (suitable for missions to Mars

or Venus). During the Phase I effort SSG will

demonstrate the feasibility of the material based on

the MIRO requirements. Analytical models will be

used to generate a conceptual model of the off-axis

Cassegrain reflector system and project the weight

savings obtained with the CFRC SiC material.

Empirical testing of a smaller MIRO mock-up, and

a number of smaller test coupons, will be used to

demonstrate thermal stability, surface finish and

surface figure capabilities, mechanical strength, and

microwave reflectivity. The results of Phase I will

provide a basis for fabricating a full-scale MIRO

prototype during Phase II.

Potential Commercial Applications (Limit 200 words)

The lightweight and low-cost nature of RBO SiC

and CFRC SiC make it very desirable for a number

of airborne and space-based sensor applications of

interest to NASA, DoD, and commercial aerospace

primes. SSG has been successful in transitioning

SiC materials to Phase III applications which

require visible quality optical performance

(DS1/MICAS, EO1/Landimager), the proposed

SBIR will extend the use of these materials to a

whole new set of applications.

Name and Address of Principal Investigator (Name,

Organization Name, Mail Address, City/State/Zip)

Joseph Robichaud

SSG, Inc.

65 Jonspin Road

Wilmington , MA 01887

Name and Address of Offeror (Firm Name, Mail Address,


Alan H. McEacharn

SSG, Inc.

65 Jonspin Road

Wilmington , MA 01887