Magnetic



Magnetic Test Site

The Spacecraft Magnetic Test Facility (SMTF) 13m coil system is one of the three known spherical coil systems of this size in the world. Its geomagnetic field cancellation system is capable of cancelling the Earth's magnetic field within a 1.83m (6’) diameter sphere. The SMTF also has a set of 2.9m diameter Helmholtz coils available for perming and deperming spacecraft, and 1.22m and 1.83m diameter coils for magnetically cleaning smaller test items.

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Magnetic Dipole Moment Testing

Zero field is first established in the center of the coil. A reference standard proton magnetometer is used to calibrate the coils.

For each measurement sequence, the test item and facility dolly are moved to the center of the coil. As the dolly is rotated 360 degrees, three-component magnetic field data is obtained at 10-degree increments.

The data are then stored in the computer for immediate display and processing. If the test item exceeds its test limit, compensation magnets can be developed to reduce the dipole moment to acceptable levels.

Spacecraft Magnetometer Calibration

Initial setup is similar to magnetic dipole moment testing. The test item is positioned in the center of the coil and aligned with the coil axes.

Static and dynamic fields are generated to establish linearity, frequency response, zero offset, and alignment characteristics of the test item.

The data system can be used to collect, store, and display test parameters.
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Parameters

Static Field Magnitude
± 60,000nT

Static Field Resolution
± 0.1nT

Static Field Noise
± 0.5nT

Static Field Homogeneity
0.001% (1.83m, 6’ diameter spherical volume)
Dynamic Field Magnitude
± 60,000nT

Dynamic Field Resolution & Stability
± 2% Frequency: 0 to 100 rad/sec

Physical Characteristics

Coil Access Opening
3.05m (W) x 3.05m (H)

Building Access Opening
4.27m (W) x 4.57 (H)

Hoist Lifting Capabilities (4)
4,536 kg , 2,722 kg, and two each 2,268 kg

Personnel

Robert Houle
EMI/Mag Group Lead & Area 300 FOM
(301) 286-0982
Robert.T.Houle@nasa.gov


Andrew Mentges
EMI/Mag Test Engineer & Area 300 AFOM
(301) 286-6958
Andrew.B.Mentges@nasa.gov


Rick Palmisano
Commercialization Test Coordinator
(301) 286-5754
rick.palmisano@nasa.gov