Observer-based
digital servos for optical disk (CD) mastering station:
The system
uses an Analog
Devices ADSP2101 DSP chip to implement four servos simultaneously.
Each of the controlled axes has a bandwidth of 1000 Hz and phase
margin of 45 degrees.
Spindle
servo for magnetic disk test/development system:
The spindle is
phase-locked to a synthesized reference clock and is fully
programmable for speeds from 300 to 12,000 RPM. Acceleration and
deceleration ramps are under velocity control.
Digital
capstan servo for very low speed arcuate-scan computer backup tape
drive:
80C196KR based servo applies quadricorrelator techniques to
an incremental encoder to achieve wide bandwidth (>100 Hz) at
arbitrarily low tape speed. This demonstration system is currently
being adapted for a commercial product.
Digital
servo for reaction wheel used in attitude control of a low earth
orbit communica-tions satellite:
An ADSP2101 controls wheel speed
and acceleration and implements control communications.
Circuit
design and component selection consulting, printed circuit design,
EMI testing (CE Mark qualification) for a line of mass flow
controllers used for precise control of gasses used in semiconductor
processing equipment.
Development
of barometric calculator used to compute parachute release settings
based on landing zone elevation. Calculator measures landing zone
barometric pressure, calculates equivalent MSL elevation, and
computes release setting for a given above-ground altitude. Calaway
& Brooks designed, packaged, and assembled these calculators.
Development
of a Time-Division Multiplexer to enable recording of up to eight
channels of data on a single channel, 8MHz recorder. The TDM-8E
makes extensive use of 30MHz clock rate FIR digital filters for
anti-aliasing and dual port memory for time-compression and
expansion. All functions, including channel gains and offsets, are
remotely settable via IEEE-488 and serial ports and also by a
Windows-based virtual front panel.
Upgrade
of cockpit annunciators used in commercial cargo aircraft. The
redesigned assemblies replace the original relays and incandescent
lamps with electronically dimmed LED lamps for significant savings in
power, weight, and reliability.