Vulcan TP/PDA

(Thermophysical Properties / Power & Data Acquisition)

An electromagnetic levitator designed for positioning, manipulating, melting and sensing metallic samples on-board the International Space Station.  Experimental capabilities enable a range of molten metal thermophysical properties to be measured.  The device and the engineering development and science team is shown below.  An overview of the system capabilities is also described below.

Overview

Vulcan-TP/PDA^TM is an International Space Station EXPRESS Rack-mounted experiment designed to acquire select thermophysical properties data from up to 17 spherical metal samples ranging in size from 4.5mm-6mm in a containerless environment.  Vulcan-PDA^TM provides power, command and data, and thermal interfaces between the Vulcan^TM system and EXPRESS Rack.  Vulcan-PDA^TM also supplies power, command and data, and internal system cooling interfaces to Vulcan-TP^TM.  Vulcan-TP^TM contains the science instrumentation, vacuum system, sample handling system, and RF system. Vulcan-TP/PDA^TM successfully completed its Phase III Flight Safety Review in May 2003.  Open Phase III Flight Safety verification and open EXPRESS Rack verification closures are currently being resolved.

Science Capabilities

Heating Frequency:  Approximately 360 KHz

Computer Specs:  PC104 format / 266 MHz / 128 MB RAM / 18 GB HD space / Embedded NT OS

Data Acquisition System:  Eagle Systems / 12 bit / 1 Hz - 2 KHz Science Data Acquisition Rate

Data Downlink Rates:  Engineering Telemetry 1 Hz / Science & Data File Telemetry Downlink Rate 1 to 20 packets/sec up to 512 K bits/sec (user definable)

Imaging Capability: 

    VCR (qty:2):  Sekai ADVCR-101 /  2 hour record time / mini DV format / Y/C input

    Camera (qty:2):  ELMO  ½” CCD / 768(v) x 494(h) pixel resolution / NTSC / Y/C output

Pyrometer:  Optical 2-color NIR:  Mikron M78, currently calibrated for a temperature range of 600-1900 °C.

Sample Position Sensor:  2-axis optical (qty:2):  ON-TRAK Photonics, PSD-2L10SP detector & OT-301DL sensing amplifier

Vacuum Pump:  Turbomolecular:  Alcatel ATH-31+ with ACT 201H miniboard controller, ultimate pressure ~10^-9 Torr, 42K RPM

Vacuum Gauge:  MKS/HPS Series 901 microPirani/Piezo sensors, 760 Torr to 10^-5 Torr

 

ISS XPRESS Rack Interface

Volume: two double mid-deck equivalent lockers and supporting hoses and cables

Mass: 140.5 Kg

Input Power: (2) 20amp/28VDC inputs

Command and Data Interface: Ethernet

Video Downlink: Realtime analog video downlink via ISS video link when available and/or digitized MPEG video via telemetry downlink

Cooling Interface: Moderate Temperature Loop

Vacuum Interface: VES (Provides roughing vacuum to Vulcan-TP^TM)

 

System Monitoring Capabilities 

System is designed to be largely self-monitoring and self-safing via the Vulcan^TM on-board computer by monitoring system sensors, which include:

  (9) Temperature sensors monitoring cooling system, external covers, and vacuum pump

  (1) Water loop pressure sensor

  (1) Water pump tachometer

  (1) Vacuum pump tachometer

  (1) Vacuum gauge

  (1) RF Current input

  (1) Bus 2 Voltage

  (1) Flow Switch

 

Ground Control

Command and data interface through Auburn University Vulcan^TM Control Room

Active commanding of system, including science operations

Active monitoring of Vulcan system health

Active monitoring of low-rate science data

Daily operations entail approximately 4 hours of system activation and science operations followed by approximately 4 hours of high-rate data and video downlink from ISS.