USRA Houston Repository

CONTENTS: Introduction -- Geological field investigations -- Mineralogy and petrography: sampling and examination of lunar surface materials -- Geochemistry -- Passive lunar seismic experiment -- Active lunar seismic experiment -- Lunar gravity measurements -- Magnetic measurements -- Lunar heat flow measurement -- Biosciences -- Mission profiles -- Preliminary study of four-hour normal and alternate missions -- Lunar atmosphere measurement

Apollo lunar science program : report of planning teams : Part 2. Appendix

Outlines the general procedures, constraints and schedules that may be of assistance to those interested in participating in the Apollo flight program with scientific, technological or medical in-flight experiments.Introduction -- Procedure for submitting proposals for in-flight experiments -- Mission Profiles -- Launch Vehicles Spacecraft -- Environmental Design and Test Criteria -- Flight Control Characteristics -- Electrical/Electronic Interfaces -- Scientific Equipment Stowag

Apollo : in-flight experiment guide.

It is important to examine the time, motions, and energy required for the experiment in order to determine the most efficient means of carrying out the sequence of tasks involved and to make this information generally available. This report deals with the time and motions required to perform the engineering seismic experiment.by Paula G. Ables.Introduction -- Description of the seismic experiment -- Simulation conditions and test results

Ables, Paula G.

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UN ITED STATES 
DEPARTMENT OF THE INTERIOR 
GEOLOGICAL SURVEY 
fILE (Opy 
This report is prel iminary and has not 
been edited or revieweQ for conformity 
with U.S. Geological Survey standards 
and nomenclature. 
Prepared by the Geological Survey for the 
National Aeronautics and Space 
Administration 
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TECHNICAL LETTER: ASTROGEOLOGY-12 
TIME AND MOTIONS REQUIRED TO PERFORH AN 
ACTIVE SEISMIC EXPERIMr.."'NT PROPOSED 
FOR THE FIRST APOLLO LANDING 
by 
Paula G. Ables 
eIRS/lIBRARY 
LUNAR AI\ID PLANETARY INSTITUTE 
3600 B,W /l,REA BOULEVARD 
HOUSTON TX 77058-1113 
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CONTENTS 
Introduction. . . • . . . . . . . . . 
Description of the seismic experiment 
Simulation conditions and test results •• 
Simulation 1 
Simulation 2 • • 
Simulation 3 
ILLUSTRATIONS 
Figure 1. Cable and reel used in first simulation of seismic 
experiment . • 
2. Cable and reel tested in second simulation of seismic 
experiment . . . . .. .... 
3. Tape cable, container, detectors and plug tested in 
third simulation of seismic experiment • . . . . 
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TIME AND MOTIONS REQUIRED TO PERFORM AN 
ACTIVE SEISMIC EXPERIMENT PROPOSED 
FOR THE FIRST APOLLO LANDING 
by Paula G. Ables 
Introduction 
At the suggestion of the Planetology Subcommittee of the Space 
Sciences Steering Committee, an active engineering seismic experi ment 
originally proposed by J . S. Watkins, J. Cl . De Bremaecker, and M. F. 
Kane was incorporated into the Early Apollo Active Se i smic Experiment 
originally proposed by R. L. Kovach. J . S . Watkins was made co-experi -
menter for the Early Apollo Active Seismic Expe r iment with the respon-
sibility of developing the engineering seismic part of the experiment 
(sometimes called the Short Array); R. L. Kovach was appointed the 
principal investigator for the experiment wi th overa l l r esponsibility 
for the development of the experiment, and par t icula r res ponsibility 
for the development of his mortar-firing device (somet imes called the 
Long Array). 
The engineering seismic experiment was designed to provide data 
on thickness, bearing strength, and other physica l properties of the 
mare surface and on the properties of t he mat eria l immedia tely beneath 
it. These data are critical to the full i nte r pr e tation of the fine 
structure of the lunar surface and the his t ory of i t s fo rmation, and 
are also important for evaluating character is t ics of the lunar surface 
which affect safety systems, design, and condu c t of later lunar mis s i ons . 
The time for carrying out scientific t asks on the lunar surface 
during early Apollo landings is severely l imited. Al s o, the por t able 
life support system restricts the astronaut t o consuming 1600 BTU/h r 
(or under stress up to 2000 BTU/hr for 10 min). The refore, it is im-
portant to examine the time, motions, and energy required for the ex-
periment in order to determine the most effi cien t means of carrying out 
the sequence of tasks involved and to make this i nforma tion generally 
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available. This report deals with the time and motions required to 
perform the engineering seismic experiment. 
Suits for the simulations were supplied by the Crew Systems Divi-
sion, Manned Spacecraft Center (MSC) , Houston, Texas. Earl La Fevers 
was responsible for organizing the tests conducted at Houston. Gordon 
A. Swann, Joseph T. O'Connor, and David L. Schleicher, geologists of 
the U.S. Geological Survey, Branch of Astrogeology, were test subjects. 
Geophysical equipment for the simulations was built by David M. Keiffer 
under the direction of Joel S. Watkins. 
Description of the Seismic Experiment 
1. Subject removes equipment, Apollo Lunar Surface Experimental 
Package (ALSEP) and staff sections, from the Lunar Excursion 
Module (LEM) descent storage bay. 
2. Places ALSEP at suitable position. 
3. Assembles staff sections. The lower position of the staff 
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contains a squib-fired thumper for inducing energy into the 
ground. The upper portion contains a compartment for the 
seismic cable. The cable is marked at 5-meter intervals. 
Plugs seismic cable into the ALSEP, and carries the staff 
during the operation. 
Walks 20 meters from ALSEP while paying out seismic cable. 
Kneels and pushes the first detector into the ground. 
Walks 50 meters while paying out seismic cable. 
Kneels and pushes the second detector into the ground. 
Walks another 50 meters and pays out seismic cable. 
Kneels and pushes the third detector into the ground. 
The subject rises, turns around, and with the staff placed 
at the third detector, charges the capacitor in the staff and 
fires a squib. 
12. The subject then walks 5 meters back along the cable and 
places a second squib into position for firing, charges the 
capacitor in the staff, and fires the squib. This is repeated 
at 5-meter intervals to within 5 meters of the first detector 
(a total of 20 times). 
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Electronics for recording the shot times and arrival times will be 
contained in the ALSEP. The seismic line and detectors will weigh 
approximately 2 pounds. The thumper for inducing energy into the 
ground will also weigh approximately 2 pounds. 
Simulation Conditions and Test Results 
In order to determine the time required and to examine the motions 
involved in performing the experiment, simulations were carried out 
under a number of conditions. Work on the experiment has been iterative, 
the results of earlier work being used to modify equipment and procedures. 
Simulation 1 
The first simulation was performed at Manned Spacecraft Center 
(MSC) in an A4-H type of space suit at 3.7 psi and 1 g. The three sub-
jects performing the experiment had only 2 hours previous experience 
working in suits. The experiment was run five times on firm, level 
ground and once on the MSC lunar surface simulation area. The surface 
of this area is strewn with slag. 
The seismic cable was wound on an aluminum reel (fig. 1) separate 
from the staff, and attached to the staff by a length of cable. The 
subjects plugged the seismic line into the mock ALSEP, attached the 
reel cable to the staff, payed out the seismic line, and placed the 
detectors in the manner previously described. During the return phase, 
the subjects payed a shot line off the reel and simulated the firings 
at 5-meter intervals. 
The average time to conduct the experiment on firm level ground 
was 23 min 36 sec. The single run on the hard, slag-strewn surface 
required only 16 min 25 sec. The results of the tests suggested the 
following modifications in equipment: 
1. Five meters of continuously color-coded line should precede 
each detector to aid in locating the detectors while paying 
out the line. 
2. The detectors should be larger and some means should be 
devised to anchor them to the ground. 
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3. The aluminum reel should be sturdier and of different design 
to allow the line to payout smoothly. 
All subjects thought that the most difficult part of the experi-
ment was placing the detectors, and some difficulty was also encountered 
in paying out the line. 
Simulation 2 
The second simulation was performed in A4-H type of space suits 
and thermal garments at 3.7 psi and 1 g on firm level ground in the 
Hopi Buttes area of northern Arizona. The three subjects now had approx-
imately 5 hours experience in suits. The experiment was performed once 
by each subject. The equipment had been modified to include a sturdier 
reel with a longer handle of larger diameter (fig. 2). The line was 
color coded for 5 meters preceding each detector. Plugs and cable 
connections to the staff were also changed. The detectors remained 
the same. The average time for the three runs under these conditions 
was 25 min 8 sec, which probably reflects the added constraint of the 
thermal garment . The subjects thought that the detectors were still 
too small to be used successfully and were too easily pulled out of 
the ground as they payed out the line. 
Simulation 3 -
The third simulation was carried out in an ILC space suit at 2 psi 
(because the test subject had a cold) and 1 g on firm level ground at 
MSC. Pressure for the suit was supplied by an umbilical line rather 
than the backpack used in other tests. The subject now had approximateiy 
8 hours experience in a suit. Because of poor weather conditions, the 
experiment was run once. The subject began the experiment with step 4 
(see page 2). The equipment had again been modified. The seismic cable 
was a tape, which was folded accordion style and fed out of a flat com-
partment (fig. 3) attached to the staff. The detectors were larger and 
each contained a I-inch spike for anchoring it into the ground. During 
the return phase along the seismic line, no shot line was payed out. 
The time required to perform the experiment was 11 minutes, the result 
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Figure l.--Cable and re e l used in first simulation of seismic experiment. 
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Figure 2.--Cable and reel tested in second simulation of seismic experiment. 
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Figure 3 .--Tape cabl e , containe r, d e t e ctors and plug tested in third 
simulation of s e ismic ex periment. 
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of the greatly increased mobility of the ILC suit and the relative ease 
of using the equipment in its present form. The decrease in pressure 
as compared to previous tests and the umbilical cord were also factors 
in the decreased time. An increase in suit pressure and the added weight 
of the backpack would increase the time required. 
Table 1 summarizes the results of the simulations and gives a com-
parison of the times required to perform individual tasks during the 
experiment. 
Table l.--Comparison of times required to perform 
individual tasks during the seismic experiment 
Tasks * Simulation 2+ Simulation 3* Simulation 1 
Plugging seismic line 
into LSEP 40 sec 2 min 6 sec 5 sec 
Plugging seismic line 
into staff 25 sec 1 min 14 sec 
Walking speed 18.8 m/min 21. 1 m/min 50 m/min 
Placing detectors 2 min 3 sec 2 min 14 sec 
Return phases 10 min 6 sec 10 min 6 sec 7 min 49 sec 
Total time of test 23 min 36 sec 25 min 8 sec 11 min 
* The data is an average of 5 trials . The one test on the slag 
surface is not included. 
+The data is an average of 3 trials. 
*the data is based on 1 trial . No shot line was payed out during 
the return phase. 
§The return phase includes all firings at 5-meter intervals while 
walking 100 meters, then 20 meters to LSEP and unplugging seismic line. 
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Apollo lunar science program : report of planning teams : Part 2. Appendix

Apollo : in-flight experiment guide.

Time and motions required to perform an active seismic experiment proposed for the first Apollo landing

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