HASI is composed of 4 subsystems:
the triaxial accelerometer (ACC), the deployable boom system
(DBS), the stem (STUB) carrying the temperature sensors,
a Kiel probe pressure inlet, an acoustic sensor and the data processing
unit (DPU).
HASI Block Diagram. In light blue the
Huygens Probe descent module.
The scientific measurements are performed
by four sensor packages: the accelerometers (ACC),
the temperature sensors (TEM), the Pressure Profile Instrument (PPI)
and the Permittivity Wave and Altimeter package (PWA).
HASI Sensor Packages
HASI subsystems accomodation on the experiment
platform of the Huygens probe. TEM, PWA and the Kiel probe of PPI are mounted
outside the Huygens probe, The BOOMs are stowed under the thermal shield
of the Probe during the interplanetary cruise and are deployed at the beginning
of the descent in Titan's atmosphere. The STUB insures that the sensors
are appropriately located and oriented with respect to the gas flow during
the measurement. ACC is located on the Huygens probe experiment platform
at the center of gravity in the entry configuration.