Obadiah Poster - OPRA

1
Automated Data Acquisition for an Infrared
Spectrometer Lauren Foster 1, Obadiah Kegege 2,
and Alan Mantooth 2,3 1 Manhattan College,
Bronx, NY, 2 Arkansas Center for Space and
Planetary Sciences, University of Arkansas,
Fayetteville, AR. 3 Department of Electrical
Engineering, University of Arkansas,
Fayetteville, AR.
Automated Integrated System

• Background of Research
• OPRA
• - Optical Probe for Regolith Analysis
• A NASA funded project currently under
  development by the University of Arkansas
• Current data
• - Obtained manually
• - Insertion withdrawal of a probe
• in regolith (loose soil and rock)
• - Data acquisition
• Future data
• - Obtained from an automated control system
• - Acquire, store and analyze data
• - From infrared spectrometer on a robotic arm
  or rover

• Operating Procedure
• The operator specifies operating mode
• - (1) Constant Velocity
• - (2) Constant Force
• Press start data acquisition
• System will create relationship between
• - Regolith Strength vs. Depth
• Obtain IR data
• (1) Constant Velocity Mode
• - Probe is inserted at constant speed
• to a designated depth
• - Penetration Force vs. Depth recorded
• - IR data taken
• (2) Constant Force Mode
• - Probe is inserted at constant force
• - Probe inserted until balanced by the
  resistance
• strength from the regolith.
• - Penetration Depth vs. Time recorded
• - IR data taken

Motor
PLC

• HMI (Human to Machine Interface)
• Automated System controlling
• - insertion, withdrawal, and data acquisition

Spectrometer on Rover
fiber optics to IR module
window over the fiber optic illuminate and sense
elements

• Objectives
• Design, assemble and program all electrical and
  mechanical parts of the automated control system
• Produce an OPRA prototype to acquire IR
  (infrared) data for spectrometer on a robotic arm
  or rover

• Data Storage and Plotting
• Computer
• - Force and depth data stored
• - Data plotted for analysis
• IR data stored by onboard spectrometer

• Analog Sensor Interface
• Analog sensors
• - Force, Depth, Speed
• Example
• - Wheatstone bridge is very common for design
• The circuit is balanced if Ssensor _ Vout 0
• Where Rsensor is the resistance of an analog
  sensor at reference voltage

Control of Speed and Force of the Probe

• Conclusions
• The automated system will be very helpful for IR
  data acquisition, plotting, and analysis
• It will also help to characterize strength of
  regolith at each depth

and

• Acknowledgements
• I would like to offer my thanks to all
  individuals who advised me, especially my fellow
  participants in the OPRA project. It is an honor
  to be part of a project that may one day find its
  way to the Moon or Mars.

For feedback controls

• Calibration
• Software calibration done such that the sensor is
  balanced at a given reference value
• Output scaling done from the HMI tag formulas

• References
• Ulrich et al. (2006). Fiber Optic Spectral Array
  on a Regolith Probe for Surface and Sub-Surface
  Mineralogical Profiling Optical Probe for
  Regolith Analysis, Arkansas Center for Space
  Planetary Sciences, University of Arkansas