(Sanitized) PROPOSAL P63-171

• Document Type: CREST
• Collection: NGA Records (Formerly NIMA)
• Document Number (FOIA) /ESDN (CREST): CIA-RDP78B04770A002900040009-9
• Release Decision: RIPPUB
• Original Classification: K
• Document Page Count: 58
• Document Creation Date: December 28, 2016
• Document Release Date: June 28, 2005
• Sequence Number: 9
• Publication Date: December 18, 1963
• Content Type: LETTER

TAT.,, Appro
I
4r n g t . 4.00
Declass Review by NGA.
13 December 1963
,-63-171-1
TAT
TAT
In response to your request made during the recent
Subject: roposal P63
Geutlemen:
isi` by
I STAT
is pleased to present a revised proposal for the Vertical Reference
Unit and Photo .Recordep.
each additional system - bimonthly thereafter
Type of Contract: Oat plus fixed fee
Validity period: 9C days
FS 0. B. Final inspection and acceptance Point:
Delivery: Prototype System 9-IZ months
Item Quantity Descri - tion
I i Design Fabricate Oroto~{
type Vertical Reference
Unit & Photo Recorder
2 Additional Units Item 1
3 4 Additional Units Item 1
4 9 Additional Units Item 1
5 - Qualification Test to
6 1 Altitude Variation System
7 2 Additional Units Item 6
8 4 Additional Units Item 6
9 9 Additional Units Item 6
LEGIB
Approved For Release 2005/07/13: CIA-RDP78B04770A0
ILL
STAT
STAT
GIB
 Appro
09-9
18 December 1963
P63-171
If further information is desired please do not hesitate tO
contact the undersigned.
Very truly Yours,
z:ja
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13 : CI?87A0 (E4000?9~9
0
TECHNICAL PROPOSAL
FOR A
RE ;LADING VERTICAL
REFERENCE SYSTEM
1
Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
S
TABLE OF CONTENTS
I
I. Introduction
II. General System Considerations
A) Vertical Reference Unit
B) Data Recording System
C) Altitude Variation System
III. Detail Description
A) Vertical Reference Unit
B) Data Recording System
C) Altitude Variation System
V. Specifications
List of Illustrations
Figure 1 - Vertical Reference Unit Schematic
Figure 2 - Block Diagram Data Recording System
Figure 3 - Lamp Display Panel
Figure 4 - Camera-Panel Configuration
Figure 5 - 35mm Film Format
Figure 6 - Mechanical Schematic-Absolute Pressure
Transducer
Figure 7 - Schematic-Altitude Servo
10
12
16
Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
0
INTRODUCTION
The recording vertical reference system, as proposed
herein, is intended for use in a high performance airborne
vehicle equipped with a complement of photographic cameras.
With the cameras fixed to the aircraft it will be
necessary, in order to properly interpret and reduce the
photographic data, to have an accurate recording of aircraft
attitude at the time of exposure.
The proposed system is comprised of an improved
vertical reference unit and a data recording system as an
integral part thereof. The configuration of the vertical
reference unit is such that the effects of disturbing torques
about all three reference axis is minimized thereby allowing
a choice of more reliable shaft position transducers for data
recording.
The complete system concept is also based upon the
minimization of weight and with the utilization of proven
components throughout, thereby insuring high reliability in
performance.
Also included is a proposal for an Altitude Variation
System, the output of which is a digitized form of the change
in altitude of the vehicle.
Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
0
II. GENERAL SYSTEM CONSIDERATIONS
A) Vertical Reference Unit
The requirement for a recording vertical reference
unit presents slightly different design criteria than that
associated with conventional camera stabilization systems.
Its function in a high performance reconnaissance aircraft
is to provide accurate and smoothed attitude data in order
to permit corrections to photographs taken from fixed cam-
eras. The problem of short term steadiness for the dura-
tion of exposure now becomes one of long term steadiness or
smooth tracking of aircraft motions.
This performance requirement is best met by a plat-
form having inherent gyroscopic stability rather than only
the inertial stability usually supplied by the camera, since
the inertial stability of such a reference unit is small com-
pared to a camera mount. Such a platform will provide the
long term stability and will also be capable of driving suitable
angular position transducers which can be read 'cittt by the
remote data recording system.
In addition since the vehicle is highly maneuverable
provision should be made for large angular freedom so that
the vertical reference is not disturbed thus requiring extra
time for erection after turns.
Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
S
B) Data Recording System
The function of the data recording system is to monitor
and record the vehicle's attitude in roll, pitch, azimuth,
absolute time, and altitude - all at the instant of the exposure
command to the main reconnaissance camera. The acquired
data is subsequently ground processed for visual and/or
computer readout for photo reduction and interpretation.
Mission requirements for the acquisition of a large
number of photographs dictates that, in order to minimize
weight, data is to be recorded only on command, in lieu of
continuous recording, and that the system be completely
automatic thereby emphasizing highest degree of reliability.
The choice of the proposed data recording system is
based upon the following considerations:
1) Shaft position encoders-A13 digit absolute type, gray
code (cyclic binary) encoder is chosen from the many
types available. Although incremental encoders yield
less weight and are available in 'pancake' configuration
they require peripheral equipment, such as up-down
counters, for direction sensing (thereby increasing
system weight), and in the event of intermittent power
failure they will not be capable of maintaining the shaft
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
0
0
position 'count'. In contrast to the incremental type the
absolute type of encoder requires no additional logic
circuitry and is capable of keeping the count, since the logic
is directly applied on the encoder disc.
A Gray code is chosen for two reasons. It requires
the least number of digits (as in natural binary) for data
recording, resulting in less weight and higher reliability
and, in contrast to natural binary, there is no ambiguity
of the count since only one digit changes at any one time.
The form of the final data reduction information will, of course,
depend upon the data handling system. Translation equipment,
to convert from the Gray code to any other form may be
required but, if desired, other codes such as BCD, Excess
three BCD, etc. , can be substituted for the Gray coded
encoder at no additional cost.
Finally, a 13 digit per turn encoder is chosen yield-
ing a resolution of approximately 2.6 arc minutes of shaft
position. Although higher resolution encoders are readily
available it is felt that their greater size, weight, and cost
would not justify their use since the stated resolution is
compatable with the platform verticality.
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
?
9
2) Data Recording - In consideration of the vehicle mission
requirements it is concluded that frame photography of a
lamp display panel is the most advantageous. The state of each
lamp depicting the shaft positions, absolute time and altitu.de
if desired. is photographed on command by a high rate single
frame camera. Film is used only when interrogation is
performed and, in addition, all the data is presented together
(in parallel).
Much thought was given to the possible use of a magnetic
tape recorder. This method would require a high tape capacity
since, throughout the flight duration, tape will be taken-up
even when the system is not interrogated. It was thought
possible that start-stop commands could be incorporated
in the tape drive but, on the basis of high interrogation rates,
the required tape drive response was not practical when
reliability was considered. Furthermore, each data would
require serial presentation to the five track tape recorder,
requiring five separate shift registers between each transducer
and the recorder, resulting in more weight and a decrease in
reliability.
Another consideration in magnetic tape recording is
the unreliability in data notation due to tape 'drop-out'.
Although great advances have been made to minimize this
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
?
?
effect, by use of a more costly, quality controlled, instru-
mentation tape the state of the art is such that it still exists
creating the possibility of losing some data.
The proposed panel lamps, having an initially long life,
will be operated at a derated value and pre-biased at a low
level, thereby extending their life many-fold. The proposed
camera is chosen for its high reliability and accurate pin
registration, with a mechanism having been much proved in
service.
C) Altitude Variation System
If an altitude variation system is to be of value it must
retain its accuracy and exhibit high reliability when exposed
to temperature variations as well as a vibration environment,
and a design approach such as employed for conventional
altimeters, whether displacement or force balance, will
not be adequate for high resolution altitude variation sensors.
To meet these requirements friction levels must be
minimized and every effort must be expended to assure low
hysteresis. In addition, the effects of thermal gradient must
be minimized and the sensitive elements must be arranged
so that the modulus variation with temperature either cancels
or produces a negligible .effect. Since the geometric config-
uration of such systems is utilized as an analog to compute
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
?
0
a ratio, relative shifts of the elements due to temperature
or vibration must be eliminated or minimized.
Operation in acceleration and vibration environments
requires a mass balance of the sensitive elements usually
meaning added weight which contributes nothing to the measure-
ment mechanization.
In some transducers efforts to reduce the friction
level have resulted in so called floating elements which shift
position during acceleration and vibratory loading, upsetting
the geometry and introducing errors.
The proposed Altitude Variation System consists of
two units: the Absolute Pressure Transducer, schematically
shown in Figure 6, and the Altitude Servo, shown in Figure 7,
the description of which will be later explained.
Noting the problemmatic areas, stated above, in various
altitude sensing systems the design selected
either eliminates or minimizes these problem areas through
the following features:
1) Use of cross spring flexure pivots minimizes friction.
The only remaining source of friction is due to slight
movement of balls in ball cage.
Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
2) Materials used in all elements have equal coefficients
of expansion--no shifts due to temperature.
3) Use of flexure pivots provides for invariant geometry.
No shift due to acceleration or vibration loading.
4) Bellows and flexure pivots have a low spring rate and
inductive pickoff is a bridge type with resolution in
the micro inch range. This eleminates the need for
spring rate compensation with permanent magnets and
the attendant change in sensitivity with temperature
due to thermal geometric variation and thermal
magnetic modulus variation.
Transducer uses cable type isolators for vibration and
shock loads and provide more effective vibration isola-
tion than conventional shock mounts.
6) Force balance principal and high sensitivity pick-off
permit motions only in the order of micro inches thus
making hysteresis effects negligible.
7) Symmetrical design configuration permits mass balance
without addition of counterweights thus eliminating
shifts during acceleration or vibration.
8) Inductive pick-off is electrically balanced and mechan-
ically symmetrical which makes its null and perfor-
mance unaffected by temperature.
?
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
?
?
i
9) Use of proportional servo system instead of contact
servo eliminates the need for a radio noise filter.
10) Torques generated by the input pressure are separated
by two elements and balanced against each other instead
of acting on the same element and resolved. This permits
closer geometric control and eliminates another source
of errors.
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
0
III. DETAIL DESCRIPTION
A) Vertical Reference Unit
The proposed vertical reference unit is depicted in schematic
form in figure 1. It contains three gyro wheels labeled A, P and R
for azimuth, pitch and roll. The pitch gimbal contains two single
degree of freedom gyros, the pitch gyro providing stability about the
pitch axis and the roll gyro providing stability about the roll axis.
If there were no frictional restraints or other disturbing torques
such as cable restraints, slip ring friction or unbalances about either
the pitch or roll axis then the pitch gimbal would remain fixed rela-
tive to inertial space. However, such disturbing torques do exist
for a variety of reasons. A disturbing torque about the roll axis will
cause the roll gyro to precess about its sensitive axis, which is
perpendicular to the roll axis, without platform motion about the
roll axis. If we detect this precessional motion relative to the pitch
gimbal and through a servo apply a torque to the roll gimbal so as
to precess the gyro back to its original position then the energy dissi-
pated in the system through the original precession has been restored
and the disturbing torque whatever its origin is eliminated. Apply-
ing the same logic to the pitch and azimuth gyros it becomes apparent
that the effect of disturbing torques on platform performance can be
made negligible and it is obvious that the only source of friction which
affects performance is the bearings on the sensitive axes.
Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
is
In the proposed design we intend to utilize the present
ARG-5 gyro wheels with an angular momentum of 6. 82 x 106
gm-cm2/sec, which is more than adequate, for all three gyros.
The deviation from perpendicularity with the pitch gimbal of
the roll and pitch gyro spin axes will be detected by a constant
reluctance rotary differential transformer. The error signal
from this detector is amplified and drives the roll and pitch
torquers. The azimuth gyro spin axis parallelism with the
plane of the pitch gimbal is also detected by a constant reluctance
rotary differential transformer whose error signal is amplified
and used to power the azimuth servo motor.
The erection system consists of the same pendulum
assembly used on the ARG-5 gyro, a two channel erection
amplifier and gyro torquers. The erection amplifier is the
integrating type with provision for erection cut-out during
turns or maneuvers. The rotary unbalanced pendulum assembly
senses the vertical through inductive pick-offs the output of
which is utilized as an erection signal and erects the gyro
through a torquer on the sensitive axis.
The azimuth gyro will precess about its sensitive axis
if a disturbing torque exists about the azimuth axis and thus cause
the azimuth servo to compensate by applying a torque about the
azimuth axis. A torquer is provided on the azimuth gyro
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
sensitive axis which enables it to be precessed to any desired
position. A synchro can be provided on the azimuth axis which
through the torquer will permit slaving to a compass system
or a navigation system.
B) Data Recording System
1 - With reference to Figure 2, 'Block-Diagram, Data
Recording System', the roll, pitch and azimuth encoders are
mechanically driven by their respective reference platform
shafts and having the capability of indicating ?80?, ?400, and
continuous 0-360? excursions, respectively. The altitude
encoder is mechanically driven by the altimeter and having a
capacity of 81, 920 feet. All four encoders are an absolute Gray
code type with a resalution of 13 digits per turn. This results
in non-ambiguous code signals with shaft position resolutions
of 2. 6 arc minutes for the three attitude encoders and 10 feet
for the altitude encoder. Since the code is absolute (the
coded pattern on the encoder disc) intermittent power failure
will not lose the shaft position count.
The time reference unit is driven by a crystal oven oscillator
the stability of which can be furnished in any range up to 1 part
in 109 per week. As an example of stability of 1 part in 108
per week will result in an oscillator drift of approximately 1
O
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
millisecond in a 24 hour period, for an oscillator of 1
megacycle per second basic frequency. The output of the
unit is also in Gray code giving the count in universal time.
The counter is started by a signal from a receiver tuned to
a universal time transmitting station, such as WWV.
Outputs from all transducers are then given sufficient
amplification to drive the lamps mounted on the display panel.
Upon interrogation the framing camera photographs the state
of each lamp on 35mm film.
The output from each of the four amplifiers is a dc level
for a binary 1 and zero output for a binary zero. As the vehicle
attitude changes so does the bit representation, in parallel, on
the lamp display panel. Similarly, output from the time reference
unit changes the state of the time channel lamp bank.
It is proposed that at the instant of shutter actuation of the
primary reconnaissance camera an interrogation pulse be
provided to the framing camera. Since the data lamps are always
energized the framing camera photographs all of the bit information
on signal. An output from the time reference unit is also provided
to all of the recon cameras for subsequent time correlation
between recon photographs and attitude information. It is
envisaged that this time signal activate lamps, located in the
data box of each recon camera, through a suitable shift register.
Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
As the individual camera shutter is energized a switch closure,
or pulse, is applied to the shift register to dump the individual
running time count on to the lamps. Suitable data optics
will then image the time data lamps on to the focal plane.
2 - With reference to Figure 3, 'Lamp Display Panel',
all data information is represented by a matrix ZO bits long
by 5 bits wide. Number 1 bits depict the most significant
digit, number 20 the least significant digit for time, and number
13 the least significant for the other data. Since roll and pitch
must be direction sensing (?80?, ?40?, respectively) number 1
digit is used for sign. When this lamp is on the vehicle attitude
is in the positive side of reference zero, and when it is off
negative side of zero is represented. The remaining lamps of
these two data depict an increasing count from either side of
zero.
Since azimuth requires continuous rotation the full 13
bit lamps are lit when azimith 359? 57'.4 is reached. Crossing
over zero azimuth resets all the lamps to zero (all lamps de-
energized). Increasing azimuth energizes the lamps starting
with bit 13.
Altitude is also represented by 13 bits, corresponding to a
total of 81, 920 feet. Each 10 foot change in altitude changes
the state of each bit starting with bit 13 at sea level. Altitudes
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
I
higher than 81, 920 feet will show as the altitude difference
between the actual altitude and 81, 920 feet.
The capacity of the time reference unit is 24h 00m 00.0
With a resolution of 100 milliseconds this total time is represent-
ed by 20 bits. Exceeding 24 hours reset the lamps and the time
count again recycles. Although a resolution of 100 milliseconds
is herein proposed resolutions up to 1 millisecond can be provided
with the addition of 7 more binary stages. This, of course,
would require more weight and space.
The proposed lamps are rated at 6V, 150 ma but will be
used at 80% of their rated voltage and pre-biased. Published
data have shown that this type of service results, for all
practical purposes, an infinite life.
3 - Figure Number 4 shows the proposed configuration of the
data photographic system. The camera is a Flight Research
Model 207, pulse-operated, and incorporating a 1000 foot
35 mm film magazine, sufficient for 5000 exposures. Its
mechanism has been proven in service, exceeding a life of
41, 000, 000 cycles at a pulse rate of 6 pulses per second.
It has fixed pin registration, ensuring an image orientation
with respect to the film sprocket holes and focal plane markers
to ?0. 0005 inches. This feature renders a less sophisticated
film reader for data reduction. The camera can operate at a
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
9
9
shutter pulse rate of 12 per second.
The lens is a standard 35 mm focal length, operating at
an object distance of 5 1/2 inches and a minification of 3. It
need not be a sophisticated design since its function is only
to transfer a contrast ratio rather than resolution, field
flatness, etc. Its speed will probably be between an F/2. 0
and F/3.5, depending lamp brightness, film speed and minimum
duration between the recon cameras exposures.
4 - The final film format is shown in Figure 5. Two frames
are shown for data of roll, pitch, azimuth, altitude and time.
The four indices may be used for automatic frame alignment
in the film reader, but, it is likely, they may not be required
since the accurate camera pin registration may be sufficient
for orientation of the frame relative to the sprocket holes.
The film reader may automatically read the film 'on the fly'
or on a frame-by-frame basis.
C) Altitude Variation System
1 - General Description
With reference to Figure 6, the Absolute Pressure Trans-
ducer consists of two symmetrical pivoted plates, nested in a
manner such that their pivot axes, which are perpendicular
intersect at a common point. The inner plate contains four
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
S
bellows all of equal effective area so disposed such that a pure
couple is produced about the inner plate pivot axis proportional
to atmospheric pressure Pa. The outer plate contains two
reference springs of equal spring rates and configured in
such a manner as to provide a reference couple about the
outer plate pivot axis. These torques are opposite in sense
and thus oppose each other through a set of ball pivots which
are positioned along a line in the plane of the pivot axes
parallel to the outer plate pivot axis. This provides one
variable lever arm, as represented by the ball pivot position (x)
and one constant lever arm,as represented by the ball pivot
track distance (c). Thus the position of the ball pivots is
dependent upon atmospheric pressure supplied to the Pa. bellows
and, as will be shown later, is a linear indication of the atmo-
spheric pressure.
If the unit is originally set up so that at torque balance
the plates are parallel then plate motion will denote unbalance
This plate motion is detected by the inductive pick-off, the
output of which after amplification causes the servo motor
to rebalance the system through associated gearing. The
rack synchronizing gear translates the racks, carrying the
ball pivots, in opposite sense and to such a position as to
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
s
0
bellows all of equal effective area so disposed such that a pure
couple is produced about the inner plate pivot axis proportional
to atmospheric pressure Pa. The outer plate contains two
reference springs of equal spring rates and configured in
such a manner as to provide a reference couple about the
outer plate pivot axis. These torques are opposite in sense
and thus oppose each other through a set of ball pivots which
are positioned along a line in the plane of the pivot axes
parallel to the outer plate pivot axis. This provides one
variable lever arm, as represented by the ball pivot position (x)
and one constant lever arm, as represented by the ball pivot
track distance (c). Thus the position of the ball pivots is
dependent upon atmospheric pressure supplied to the Pa. bellows
and, as will be shown later, is a linear indication of the atmo-
spheric pressure.
If the unit is originally set up so that at torque balance
the plates are parallel then plate motion will denote unbalance
This plate motion is detected by the inductive pick-off, the
output of which after amplification causes the servo motor
to rebalance the system through associated gearing. The
rack synchronizing gear translates the racks, carrying the
ball pivots, in opposite sense and to such a position as to
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
balance the plates and null the induction pick-off. The rack
position (x) is therefore a direct measure of the atmospheric
pressure (Pa). as is the potentiometer driven by the rack. The
potentiometer serves as one leg of a balanced bridge, as shown
in the altitude servo schematic of Figure 7.
The following is a treatment showing the linear relation-
ship between the inlet atmospheric pressure and the transducer
output:
The inner plate torque is 2'Pa A' b' and the outer plate
torque is 2k( -a where
'Pa'. = inlet atmospheric pressure
k = spring rate of reference springs
= reference spring preload
A = effective area of bellows
a = Moment arm of reference springs
b = Moment arm of'Pa' and Vacuum bellows
then the force at the ball pivots due to the inner plate torque is
F.
1
(2 Pa) ?A'b
x
(1)
and the force at the ball pivots due to the outer plate torque is
(2)
at balance F. =F or
1 0
(3)
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
arm can all be made equal. Obviously neither the bellows
area nor the lever arms can be manufactured identically,
however, there is another bellows variable which while in
some transducers is detrimental, in this design is useful.
That is, the property that the center of the effective area is
not coincident with the mechanical centerline. Thus, since
the effective areas differ slightly and the eccentricity of the
center of pressure also varies, by rotating the bellows it is
possible to arrive at a combination where for the inner pivoted
plate the product of areas and lever arms are identical. After
these orientations are found and the bellows are rotationally
locked, then by adjusting the ball pivots lever arm the
design value of the conversion constant can be easily achieved.
This adjustment is accomplished by shims between the ball
pivot holder and the ball pivot slide.
The first step of the above calibration is accomplished
with special test equipment on the plate and bellows assembly as
a sub-assembly operation. The second step is accomplished
during final assembly and test.
Calibration shifts or instability can only occur due to
geometric changes since the output of the device is independent
of bellows area and spring rate provided no additional forces
0
Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
0
are generated by ambient temperature variations. Temperature
effects are eliminated by making the support structure of a
material which has the same thermal coefficient of expansion
as the bellows, reference springs, and the plates. Therefore,
since no mechanical compression or extension of the bellows and
springs will occur, no thermal torques will be generated, and it
is not necessary to match spring rates.
Fundamentally, the transducer operates in the near-
balanced condition at all times, resulting in infinitesmal plate
excursions. Variable torques due to bellows and springs
mechanical hysteresis are considerably minimized thereby
resulting in a highly repeatable and accurate system.
Since the geometry is invariant due to the plates and the
use of flexure pivots; and the temperature dependent physical
properties have no effect on the output, the transducer will
exhibit excellent stability throughout the temperature and
vibration environment.
In addition, there are no elements of the transducer
which will deteriorate during service and alter the calibration.
Repeated stress on the bellows, springs, and flexure pivots
could conceivably alter spring rates slightly but these have
no effect on the output and only a third order effect on the
sensitivity. However, these stresses are low and it is estimated
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
i
that no significant effect will occur short of 20, 000 hours
of operation.
The design features and calibration techniques, as
stated above, are such that the accuracy and resolution of the
altitude variation system, given in the specifications of
Section V, can confidentally be met.
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
IV FURTHER CONSIDERATIONS
?
?
1 - Incandescent lamps are proposed primarily for their
relatively high brightness output and low energizing voltage.
Their peak intensity response is such that approximately 20
pulses per second cannot be exceeded else bit changes will
not be discerned. The roll, pitch, azimuth, and altitude
encoders have a resolution of 8, 192 counts (13 bits) per
revolution. The lamps will therefor limit the slew rates of
the three reference axes to 7/8 degree per second, and for
altitude 200 feet per second. Time has a resolution of 100
milliseconds per count, a value to which the lamps can respond.
Higher slew rates can be accomplished by the use of neon
lamps, such as type NE-51, except that they require more than
100 volts for energization and have a low brightness level. If,
indeed, higher slew rates are required experiments will have
to be conducted to determine feasibility as regarde cycling
rates, shutter speeds, brightness, film and lens speeds.
2 - With reference to Figures 3 and 5, time data requires 7
more bits than the other data for a total of 20 bits. The 20 bits
are a result of a total count of 24 hours of 100 milliseconds
resolution. To fit all 20 bits in the format shown the use of
the proposed 'double frame' camera is required. A mission
requiring 5000 exposures results in the need for a 1000 foot
film magazine for the data camera. As stated in the specifications
of Section V the camera weighs 27 pounds, 12 1/2 pounds for the
Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
i
camera and 14 1 /2 pounds for the 1000 foot magazine and
film, and with a size as shown in Figure 4.
If instead of time the correlation between the recon
photos and the attitude data was in terms of frame number
a total of 5000 frames would require the same number of bits
as the other data, i. e., 13 bits. The format matrix will then
be 13 bits by 5 rows. By eliminating the seven bits the smaller
format size can be fit into a 'single frame' camera utilizing
a film magazine of only 400 foot capacity for the 5000 exposures,
in lieu of 1000 feet. This results in a weight reduction of
7 pounds and in a space saving, as shown in Figure 4. Further,
a time reference unit weighing 3 pounds will not be required,
but in its stead a 13 bit flip-flop circuitry weighing no more
than 8 ounces. This, of course, also eliminates the weight
for 7 lamps and associated amplifiers and 7 bits for each of
the reconnaissance cameras data system.
If, indeed, the 1000 foot magazine camera is retained, a
reduction of 6 pounds can be accomplished by substituting
magnesium for the aluminum housing. The camera vendor
states this can be accomplished, &t no additional cost, if
a minimum order of 10 units is placed.
24
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
?
?
V SPECIFICATIONS
A) Three Gyro reference Platform Airborne Verticality: 12
minutes of arc maximum.
Angular Freedom:
Pitch ?40?
Roll ?80?
Angular Rate: 7/8 deg/sec. with incandescent lamp panel. Higher
rates may be possible by use of neon lamps.
Size: 18" long 10" wide 12" high
Weight: 25 lbs. max.
B) Data Recording System
Resolution:
Roll, Pitch, Azimuth 2. 6 minutes of arc
Altitude Variation 0. 1% or 10 feet whichever is greater
Time Reference Unit 100 milliseconds (1 millisecond
can be furnished). Setable to Universal
Time
Accuracy:
Roll, Pitch, Azimuth 2. 6 minutes of arc
Altitude Variation 0. 2% or 25 feet whichevr is greater
Time Reference Unit ?1 millisecond per day
Cycling Rate:
Framing Camera 12 pulses per second maximum
? Camera - Panel Sub Assembly: see Figure 4
25
Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
40
0
Size (continued):
Amplifier and associated circuitry package:5x6x19
Time Reference Unit: 4x5x10
Absolute Pressure Transducer: 6x7 :5/8x4 1 /2 high
Altitude Servo: 4x6x4 1 /2 high
Weight:
Camera-Panel Sub assembly: 28 lbs. with 1000 foot
magazine,
21 lbs. with 400 foot
magazine,
Both can be reduced by 6 lbs.
and 3 lbs, respectively, in
quantity order of 10
Amplifier and Associated Circuitry package: 12 lbs.
Time Reference Unit: 3 lbs.
Encoders: 3 1 /2 lbs. This includes 14 ounces
for altitude encoder
Absolute Pressure Transducer: 4 1 /2 lbs.
Altitude Servo: 2 1 /2 lbs. This includes 14 ounces
for altitude encoder
Power Requirements
Encoders: 6. 3V dc ?5%, 1. 5 amps. maximum
Amplifiers and Associated
Circuitry ?5V dc ?2%, 100 ma. average
Lamp Drivers: -6V dc t5%, 6 amps average
26
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/1 IA-RDP78B04770A002900040009-9
ROLL
ENCODER
AZIMUTH
---BOLL: GYP-
SE~~ISITIV(
.j t
AZ; MUT ~4 . a
S E iN .S i 1 VE A X ",
P' T C JYr-(, )
SENSITIVE AXL3
FIGIRE#I
S C H E I V! i i Ti~provad tEOF~eIeickb/07/r$ - C AFR~JP 7 V~'*0029044?0T-9
P-( =, 3- 171
STAT
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
0
SYSTEM
ENCODER
0
REFERENCE
PLATFORM
ALTI 1 .1.7.>(-
VA!-;;l A rrrJ,4
ROLL
-T
PICH
40"
E N CO DER
C-AI,920 FT.
ALTITUDE
LNC(DLR
XTAL
OSCILLATOR
AMPLIFIERS I
FIGURE *2
BLOCK DIAGRAM -
AZIMUTH
EN(00L.I,
CAMERA
FROM PRIMARY
RECON CAMERA
TO RECON CAMERAS STA
Approved I-or Keiease fLU991IH1/IT3r-UV~-IKL {'l]VfWuffd 5(PWUU4000UI U -
 ROLE
800
PITCH
+400
AZIMUTH
0-360?
ALTITUDE
0-81, 920FT
TIME
0-24H
Approved For Release 2005/07/1 WIA-RDP78B04770A002900040009-9
16
2 3 4 56789 1 0 1 1 1 21 31 41 51 61 71 92 0-
18
4.5
FIGURE'3
LAMP DISPLAY PANEL
P63-171
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
STA
 0
Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
LIGHT-TIGHT 80X~
LAMP PANEL CONNECTOR
LAMP PANEL SUPPORT BRACKET-
FILM -,
PLANE
NOTE 'I
THIS (DIMENSION IS 4 "2 WITH
1000' MAGAZINE AND 3 %4' WITH
400' MAGAZINE.
CA(v?I- PA
6 .....-
- 155/
FIGURE44
C14MERA--PANE L_-CON FI GURATIO N
Approved For Release - 0fl040009-
--1000' 35 MM
MAGAZINE
-400' 35 MM
MAGAZINE
 ? Approved For Release 2005/07/13*IA-RDP78B04770A002900040009-9
^ ^
0
?0 A 0
> s? ? ?s
06 ?? f1 ?(19u11 UY?
?#w 40V
>
~? ??s?
FIGURES
35mm FILM FORMAT
C^
Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
?
P63-171
STA
 Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
r0)
10q,
C. OT
S
\-EXTENSION
ti 5
i~~T~R~NG
SPRING
7f j L_-
,
MEVHANI ~i.%L SC IEMATIG-bf-:'SCI
LUTE PRESSURE Tk~
- riaved-Fer eleas Mn . 77 - - _ 41 . 400D'
STA
 Approved For Release 2005/07/1 #IA-RDP78BO477OA002900040009-9
I N PUT
POWER
Pat
THIS PCT IS LOCATED
IN THE ABSOLUTE
PI S,JUkk. TRANSDUCER
2
FIGURE7
\
SERVO 1,
OTO
0040009-9
G rT'V ft-fr e"0t_ I - 1- V I1J I-P7 !?F~
AMPLIFIf- R
ENCODER
STA
 STAT Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 The NPIC Proposal #4064 by the
as proposal P63-171-2 was'given to this
organization for information purposes only. No
contractual action is anticipated by P&DS.
In the event the proposal is accepted b
coordination action will be taken y
is office to handle any data produced as a.
result of the proposed system.
 Approved For Release 2005/07/13 ; CIA-RDP78BO477OA002900040009-9
PROPOSAL
FOR A
RECORDING VERTICAL
REFERENCE SYSTEM
P-63-171
AMENDMENT H
it
? FEBRUARY 27, 1964
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13: CIA-RDP78BO477OA002900040009-9
0
TABLE OF CONTENTS
I.
INTRODUCTION
1
H.
GENERAL SYSTEM CONSIDERATIONS
2
A) Vertical Reference Unit
2
B) Data Recording System
2
III.
DETAIL DESCRIPTION
6
A) Vertical Reference Unit
6
B) Data Recording System
10
IV.
SPECIFICATIONS
12
0
List of Illustrations
Figure 1 - Vertical Reference Unit
Figure 2 - Block Diagram Data Recording System
Figure 3 - Camera-Panel Configuration
0
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
s
0
INTRODUCTION
The recording vertical reference system, as proposed herein,
is intended for use in a high performance airborne vehicle equipped
with a complement of photographic cameras.
With the cameras fixed to the aircraft it will be necessary, in
order to properly interpret and reduce the photographic data,. to have
an accurate recording of aircraft attitude at the time of exposure..
The proposed system is comprised of an improved vertical
gyro with synchro pickoffs, a servo repeater, and a data recording
system. The servo repeater drives shaft position encoders for
recording aircraft pitch and roll.
The complete system concept is also based upon the minimiza-
tion of weight and with the utilization of proven components throughout,
thereby insuring high reliability in performance.
Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
? II. GENERAL SYSTEM CONSIDERATIONS
A) Vertical Reference Unit
The requirements for a recording vertical reference system
presents slightly different design criteria than associated with
camera stabilization systems. The
STAT
ARG-5 vertical reference STAT
unit utilizes a capacitive pickoff with a limited range and the camera
platform containing the gyro is driven to null the error signal. This is
an ideal system for stabilizing a camera or other device which can be
mounted with its C. G. at the intersection at the roll and pitch axis.
This system concept also requires minimum gimbal axis friction and
usually about 10? of freedom.
In order to overcome the limitations of this system when used for
a recording vertical reference system it is proposed to utilize the
ARG-6 gyro which is the ARG-5 unit modified for synchro pick-offs.
A servo repeater can now be used to drive pitch and roll encoders.
B) Data Recording System
The function of the data recording system is to monitor and
record the vehicle's attitude in roll and pitch, as well as frame num-
ber and altitude - all at the instant of the exposure command to the main
reconnaissance camera. The acquired data is subsequently ground
processed for visual and/or computer readout for photo reduction and
interpretation.
Mission requirements for the acquisition of a large number of
photographs dictates that, in order to minimize weight, data is to be
-2-
Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
s
?
recorded only on command, in lieu of continuous recording, and
that the system be completely automatic thereby emphasizing highest
degree of reliability,.
The choice of the proposed data recording system is based
upon the following considerations:
1) Shaft position encoders-A13 digit absolute type, gray code
(cyclic binary) encoder is chosen from the many types avail-
able. Although incremental encoders yield less weight and
are available in 'pancake' configuration they require peri-
pheral equipment, such as up-down counters, for direction
sensing (thereby increasing system weight), and in the event of
intermittent power failure they will not be capable of maintaining
the shaft position 'count'. In contrast to the incremental type
the absolute type of encoder required no additional logic cir-
cuitry and is capable of keeping the count, since the logic is
directly applied on the encoder disc.
A Gray code is chosen for two reasons. It requires the
least number of digits (as in natural binary) for data recording,
resulting in less weight and higher reliability and, in contrast
to natural binary, there is no ambiguity of the count since only
one digit changes at any one time. The form of the final data
reduction information will, of course, depend upon the data
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
?
?
is
handling system. Translation equipment, to convert from the
Gray code to any other form maybe required but, if desired,
other codes such as BCD, Excess three BCD, etc. , can be
substituted for the Gray coded encoder at no additional cost.
Finally, a 13 digit per turn encoder is chosen yeilding
a resolution of approximately 2. 6 arc minutes of shaft position.
Although higher resolution encoders are readily available it is
felt that their greater size, weight, and cost would not justify
their use since the stated resolution is compatible with the
platform verticality.
2) Data Recording - In consideration of the vehicle mission
requirements it is concluded that frame photography of a
lamp display panel is the most advantageous. The state of each
lamp depicting the shaft positions, frame number and altitude
if desired is photographed on command by a high rate single
frame camera. Film is used only when interrogation is per-
formed and, in addition, all the data is presented together
(in parallel).
Much thought was given to the possible use of a mag-
netic tape recorder. This method would require a high tape
capacity since, throughout the flight duration, tape will be
taken up even when the system is not interrogated. It was
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
I*
?
40
thought possible that start-stop commands could be incorporated
in the tape drive but, on the basis of high interrogation rates,
the required tape drive response was not practical when relia-
bility was considered. Furthermore, each data would require
serial presentation to the five track tape recorder, requiring
five separate shift registers between each transducer and the
recorder, resulting in more weight and a decrease in reliability.
Another consideration in magnetic tape recording is the
unreliability in data notation due to tape 'drop-out'. Although
great advances have been made to minimize this effect, by use
of a more costly, quality controlled, instrumentation tape the
state of the art is such that it still exists creating the possibility
of losing some data.
The proposed panel lamps, having an initially long life,
will be operated at a derated value and pre-biased at a low level,
thereby extending their life many-fold. The proposed camera
is chosen for its high reliability and accurate pin registration,
with a mechanism having been much proved in service.
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
III. DETAIL DESCRIPTION
A) Vertical Reference Unit
The proposed unit is essentially a very accurate vertical gyro
(ARG-6) with pitch and roll servo repeaters. Assuming for the moment
negligible error in the repeaters, accuracy of the measurement is
dependent upon the degree to which the gyro can be erected and main-
tained in a vertical. An awareness of these factors and the degree to
which they degrade performance must be realized in order to properly
appreciate the choice of the system proposed.
Verticality:
A gyroscope is merely a spinning wheel and it alone does not
indicate vertical. A pendulum is therefore provided to establish the
vertical direction. Any difference between the gyro position and the
pendulum is amplified and applied to torque the gyro into alignment
with the pendulum.
Because the gyro tends to stay pointed in a fixed direction in
space, as the earth turns in space, the gyro must be continually torqued
to stay aligned with the pendulum. To produce this torque a displace-
ment error occurs between gyro and pendulum. The magnitude of the
error is dependent upon the erection loop gain employed and is re-
ferred to as "Earth's Rate Effect. "
Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
?
?
Similarly, if the gyro is carried about the surface of the
earth by a moving vehicle it again must be torqued to follow the
curvature of the earth. In an aircraft traveling at 600 mi. /hr. the
gyro must be torqued at a rate of 9? /hr. to stay aligned with the
vertical. This is called "Profile Effect".
In addition to these two effects of earth's rate and profile,
which make it necessary to keep torqueing the gyro towards verti-
cal, the gyro itself may, due to inherent restraints, drift away from a
fixed position. This drift too must therefore be overcome by a counter-
torque produced by the erection system.
Summarizing then, due to the gyroscopic effects of earth's
rate, profile, and drift a counter-torque must be produced by an error
signal in the erection loop to prevent the vertical gyro from straying
away from the vertical. In order to minimize these errors, a high
erection loop gain would seem desirable. Unfortunately, another error
affect limits the amount of gain that can be applied in this loop.
This other class of errors, namely, pendulum errors, can best
be reduced not by a high but a low erection loop gain. Pendulum errors
arise in a moving system due to vibrations and accelerations which
cause the pendulum reference to jog and swing away from vertical.
With low erection gain when the pendulum is momentarily disturbed
from its correct position, the gyro in following moves away slowly.
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
9
?
Before it has had enough time to build up an equivalent error, the
pendulum will have returned to zero and the gyro moves back. The
effect is that rapid deviations of the pendulum are not followed by the
gyro, although the gyro does take up the long term average position of
the pendulum. Indeed, it is this very feature of filtering the extraneous
motions of the pendulous reference that makes the vertical gyro a
desirable vertical reference unit.
It would therefore be advantageous to design an erection loop with
high gain to reduce the verticality errors due to gyroscopic effects and
low gain to minimize errors due to pendulum disturbances. This can be
accomplished by the use of an integrating amplifier in the erection loop
which will provide an output proportional to the error plus the integral
of the error. The advantage of this type system is to reduce the degree
of compromise between the two conflicting requirements of high and low
gain. Gyroscopic errors are long term or low frequency effects while
pendulum perturbations are short term or higher frequency effects.
An integrating erection system has just these characteristics, high gain
at low frequencies and low gain at high frequencies. The result,
therefore, is to greatly reduce gyro stand-off errors while providing
increased pendulum filtering. By virtue of the integrating erection
system gyroscopic errors such as earth's rate, profile and drift can
be kept below three minutes of arc while still providing a high degree
of filtering to pendulum perturbations.
-8-
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 0
25X1
?
0
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
As a further aid towards system accuracy, to prevent additional
verticality error due to aircraft turns, a rate switch will be provided.
Whenever the aircraft goes into a prolonged bank during a turn the
"Rate of Turn" switch will open the erection loop to prevent the verti-
cal gyro from lining up with the false position of the pendulum caused
by the centripetal force of the turn.
The vertical reference system with an integrating erection
system as described above, has already been successfully employed
by
in similar airborne systems.
Servo Repeaters:
The roll and pitch signals generated by the vertical gyro are
transmitted from their respective gimbals by pancake type synchro
transmitters whose inherent accuracy is better than 6 minutes of arc.
The servo repeaters must accurately follow this data at
rates up to 10 milliradians per second. To keep the servo tracking
error below one minute of arc the servo loops will have at least a
5 cycle bandwidth.
The roll and pitch servo repeaters consist of two phase servo
motors, a synchro control transformer and a servo amplifier.
The amplifier drives the control transformer so as to reduce the
error voltage between the synchro transmitter and the synchro
control transformer to zero, thus the motor shaft position is pro-
portional to pitch angle or roll angle. The servo motors simul-
taneously position 213 digital encoders which are interrogated on
command by the data recording system.
Approved For Release 2005/07/13 : CII-RDP78B04770A002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
?
i
B) Data Recording System
1 - With reference to Figure 2, 'Block-Diagram, Data Recording
System', the roll and pitch encoders are mechanically driven by their
respective servo repeaters having the capability of indicating ? 80?
roll and ? 40?, pitch. Both encoders are an absolute Gray code type
with a resolution of 13 digits per turn. This results in non-ambiguous
code signals with shaft position resolutions of 2. 6 arc minutes. Since
the code is absolute (the coded pattern on the encoder disc) intermittent
power failure will not lose the shaft position count.
Outputs from all transducers are then given sufficient amplifica-
tion to drive the lamps mounted on the display panel. Upon interroga-
tion the framing camera photographs the state of each lamp on 35 mm
film.
The output from each of the four amplifiers is a dc level for a
binary 1 and zero output for a binary zero. As the vehicle attitude
changes so does the bit representation, in parallel, on the lamp display
panel.
It is proposed that at the instant of shutter actuation of the
primary reconnaissance camera an interrogation pulse be provided
to the framing camera. Since the data lamps are always energized
the framing camera photographs all of the bit information on signal.
Approved For Release 2005/07/13 : CIA-RDP78B04770A002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
?
0
The proposed lamps are rated at 6V, 150 ma but will be used
at 80% of their rated voltage and pre-biased. Published data have
shown that this type of service results, for all practical purposes, an
infinite life.
2 - Figure Number 3 shows the proposed configuration of the data
photographic system. The camera is a Flight Research Model 207,
pulse-operated, and incorporating a 400 foot 35 mm film magazine,
sufficient for 5000 exposures. Its mechanism has been proven in
service, exceeding a life of 41a 000, 000 cycles at a pulse rate of 6
pulses per second. It has fixed pin registration, ensuring an image
orientation with respect to the film sprocket holes and focal plane
markers to ?0. 0005 inches. This feature renders a less sophisticated
film reader for data reduction. The camera can operate at a shutter
pulse rate of 12 per second.
The lens is a standard 35 mm focal length, operating at an
object distance of 5 1/2 inches and a minification of 3. It need not
be a sophisticated design since its function is only to-transfer a con-
trast ratio rather than resolution, field flatness, etc. Its speed will
probably be between an F/2. 0 and F/3. 5, depending lamp brightness,
film speed and minimum duration between the recon cameras
exposures.
- 11 -
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
?
A) Vertical Reference Unit Verticality: 15 minutes
of arc dynamic.
Angular Freedom:
Pitch ?40?
Roll ?80?
Angular Rate: 7/8 deg. /sec. with incandescent lamp panel. Higher
rates may be possible by use of neon lamps.
Size: 12" long 10" wide 10" high
Weight: 25 lbs. max.
B) Data Recording System
Re solution:
Roll, Pitch 2. 6 minutes of arc
Accuracy:
Roll, Pitch 2. 6 minutes of arc
Cycling Rate:
Framing Camera 12 pulses per second maximum
Camera - Panel Sub Assembly: See Figure 3
Amplifier and associated circuitry package: 5x6xl9"
0
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
0
0
Weight:
Camera-Panel Sub Assembly: 21 lbs.
Amplifier and Associated Circuitry package:. 12 lbs..
Encoders: 2 1/2 lbs.
Power Requirements:
Encoders: 6. 3V do *5%, 1. 5 amps. maximum
Amplifiers and Associated
Circuitry ? 5V dc t2%, 100 ma. average
Lamp Drivers: -6V dc t5%, 6 amps average
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 --___._-_.Approved.For Release2005/07/13: CIA-RDP78BO477OA002900040009-9
fP.~-?:..TION
Ai/'PL "F/FR
Pi TCrt
3EP'v' P..-.PFITER
FIGU
VERTICAL R
~E -u I
FERENCE UNIT
P- 63-171-2
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
ST
 REFERENCE
PLATFORM
Approved For Release 2095/07/13 CIA-RDP78BO477OA002900040009-9
YSTEM
-...._
POWER
ROLL
ENCCDCR
PITCH
N( !'FR J
I ,.: . ... ...
ff~
Fr.AMrr,
FRAME
COUNTER
BLOCK DIAGRAM-
RATA hE=CCRDIN,G SYSTEM
FROM PRIMARY
RECON CAMERA
- TO HECON CAMERAS ST/1
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 Approved For Release 2005/07/13 CIA-RDP78B04770A002900040009-9
LIGHT-TIGHT 80X
LAMP DIS}-LAI F-:+N E L-'--
400' 35 MM
MAGAZINE
STA
CANER ;'. PANEL-CONE IGUPITIKN
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
 STAT Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9
Approved For Release 2005/07/13 : CIA-RDP78BO477OA002900040009-9