Tentatively scheduled to fly on STS-17 (41G), this get away special aims to demonstrate amateur radio transmissions to global ground stations in the English language. Experiments No. 1, 2, and 3 use the micro-gravity of space flight to study the solidification of lead-antimony and aluminum-copper alloys, the germination of radish seeds, and the growth of potassium-tetracyanoplatinate hydrate crystals in an aqueous solution. Flight results are to be compared with Earth-based data. Experiment No. 4 (the Marshall Amateur Radio Club Experiment - MARCE) features radio transmissions and also provides timing for the start of all other experiments. A microprocessor obtains real-time data from all experiments as well as temperature and pressure measurements within the GAS canister. These data are to be transmitted on previously announced amateur radio frequencies after they are converted into the English language by a digitalker for general reception. The support structure for the G #007 experiments consists of two primary plates and four bumper assemblies

Henderson, A. J., Jr.

English

NASA Technical Reports Server

PROJECT EXPLORER: 
by 
GET AWAY SPECIAL #007 
Ar thu r  J .  Henderson, Jr. 
GAS EXPERIMENTERS SYMPOSIUM AT GSFC 
August 1-2, 1984 
INTRODUCTION 
PROJECT EXPLORER i s  a program t h a t  w i l l  f l y  student-developed exper i -  
ments onboard the  Space S h u t t l e  i n  one o f  NASA's "Get-Away Specia l "  (GAS) 
conta iners designated as G #007. 
Space and Rocket Center, t h e  Alabama-Mississippi Sect ion o f  t h e  American 
I n s t i t u t e  o f  Aeronautics and Ast ronaut ics  Alabama A&M U n i v e r s i t y  and r e -  
qu i res  extens ive support by t h e  U n i v e r s i t y  of Alabama i n  Hun tsv i l l e .  P r o j e c t  
Explorer  i s  t e n t a t i v e l y  scheduled t o  f l y  on October 5, 1984, on STS-17 (416). 
A unique feature o f  t h i s  GAS miss ion w i l l  demonstrate amateur r a d i o  t rans -  
missions t o  g loba l  ground s t a t i o n s  i n  t h e  Eng l ish  language. 
The program i s  co-sponsored by t h e  Alabama 
I n  1978, the  co-sponsoring agencies undertook t h i s  p r o j e c t  t o  encourage 
h igh  school students t o  become involved i n  space-oriented engineering e f f o r t s .  
A brochure was d i s t r i b u t e d  nationwide t o  h igh  schools throughout t h e  Uni ted 
States s o l i c i t i n g  proposals by h igh  school students. 
chure read: "Students, Can You See Your Ideas i n  Space ( ? ) ' I .  
posals were submitted and t h i r t e e n  students were selected. Only two o f  t h e  
o r i g i n a l  t h i r t e e n  students remai n. One a d d i t i o n a l  s tudent  P. I .  has been added 
on s ince  the  l o s s  o f  t h e  others i n  1981. 
experiments on t h e  Space S h u t t l e  and t o  ob ta in  s c i e n t i f i c  data on t h e  unique 
cond i t ions  o f  space f l i g h t ,  espec ia l l y  i n  t h e  area o f  l ow-g rav i t y  cond i t ions .  
t he  s o l i d i f i c a t i o n  o f  lead-antimony and aluminum-copper a l l o y s ,  t h e  germin- 
a t i o n  o f  r a d i s h  seeds, and t h e  growth o f  potassium-tetracyanoplatinate hydrate 
c r y s t a l s  i n  an aqueous so lu t i on .  
based data. 
The c a p t i v a t i n g  bro-  
Over 150 pro-  
The concept o f  t he  p r o j e c t  i s  t o  design, develop, and f l y  se lected s tudent  
Experiments No. 1, 2, and 3 use the  m ic ro -g rav i t y  o f  space f l i g h t  t o  study 
F l i g h t  r e s u l t s  w i l l  be compared w i t h  ear th -  
Experiment No. 4 ( the  Marshall  Amateur Radio Club Experiment - MARCE) 
features r a d i o  transmissions and w i l l  a l so  prov ide  t i m i n g  f o r  t h e  s t a r t  of 
a1 1 o the r  experiments. A microprocessor w i l l  o b t a i n  r e a l  - t ime data from a1 1 
experiments as w e l l  as temperature and pressure measurements w i t h i n  t h e  GAS 
can is te r .  These data w i l l  be t ransmi t ted  on p rev ious l y  announced amateur 
r a d i o  frequencies a f t e r  they have been converted i n t o  t h e  "English language'' 
by a d i g i t a l  ke r  f o r  general recept ion .  
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https://ntrs.nasa.gov/search.jsp?R=19840019705 2020-03-22T09:34:05+00:00Z
OPERATIONAL SCENARIO 
The G #007 Payload will require a duration of f ive  (5 )  fu l l  days and 
a "turn-on" of the experimental package as early in the Space S h u t t l e  
mission as possible. Experiment No. 1: The Sol idif icat ion of Alloys 
experiment will be s tar ted a t  a time when about 8 hours of very low "g" 
operations can be expected, such as du r ing  a sleep period fo r  the crew. 
A t  that  time, a signal from the GAS Operations Panel within the crew 
compartment wi 11 t r igger  the operation of this experiment. Subsequent 
operations will be s tar ted by bui l t - in  controls and do not need additional 
signals.  Another period o f  low-gravi ty  operations for  a second sol i d i f i  - 
cation will occur about a day l a t e r .  
Experiment No. 2: The Radish Seed Germination and Growth experiment 
must be in i t ia ted  as soon as feasible ,  .e., a t  about  the time when the 
Shuttle reaches i ts  o rb i t  t o  obtain the longest possible growth period 
for the seeds. 
for meaningful resul ts .  Operational control will be provided ,by MARCE: 
Upon the i n i t i a l  G #007 power-up, a relay will act ivate  pump "A" to  supply 
the water/fert i  lizer solution to  the seeds. Upon power-down, approximately 
120 hours l a t e r ,  another relay will act ivate  pump l1Br1 and freeze any fur ther  
seed development by the application of buffered formaldehyde to the seeds. 
An orbi ta l  operation of a t  l eas t  f ive  (5 )  days is  needed 
Experiment No. 3: The Crystal Growth experiment will be activated 
when micro-gravity conditions ex is t .  
able low-g period las t ing 4 hours or more, MARCE will power-up the elec- 
t ro lys i s  cel l  by a 1.3 V DC power supply, and crystals  will s t a r t  t o  form 
on the anode. A 35 mm camera and i t s  electronic f lash will have been 
activated a t  the same time, and will take a picture every 40 minutes. This 
experiment requires 24 hours for completion. 
Experiment No. 4: The Marshall Amateru Radio C l u b  Experiment (MARCE) 
wi 11 control a1 1 other experiments in accordance with individual require- 
ments. The "ORBITER'S ATONOMOUS PAYLOAD CONTROLLER (APC) provides AFT- 
F l i g h t  Deck control for  experiments "turn-on" and tlturn-offll and can a1 so 
terminate a l l  GAS operations i f  SAFETY NEEDS require such premature cessation 
of experimentation. 
A t  the beginning of the f i r s t  avail-  
Three transmission cycles of 8 hours each are  planned. A transmission 
cycle consists of a 30 second transmission every 4 minutes. When experi- 
ment #1 i s  act ive,  transmissions will l a s t  about 45 seconds. The f i r s t  
8-hour cycle will be activated a t  G #007 "turn-on". 
will be s tar ted dur ing  the two experiment #1 operations. 
Second and t h i r d  cycles 
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DESCRIPTION 
ALL  experiment packages and/or t h e i r  components are  mounted on a 
rectangular mounting plate ,  which i s  i n  turn bol ted to  the r i b  of a round 
plate  which is  bolted d i rec t ly  to  the GAS canis ter  t o p  l i d .  
Experiment No. 1 will  so l id i fy  two alloy samples (Lead-Antimony and 
Aluminum-Copper) inside of an internally insulated aluminum cylinder (15" 
long and 6" diameter). 
two miniature furnaces 46" H and 3/4" Diameter. (see Figure 1) .  The wall 
thickness of the cylinders are  1/16" thick. 
of lava cores and are  wrapped w i t h  Nichrome wire (spr ing  co i l s ) .  
samples a re  centrally located i n  the middle of each furnace core and can 
be heated to  temperatures of up to  7 00 C. The heat i s  generated by a 28 
VDC e l ec t r i c  current from a centra! pcwer supply. Moreover, while the 
in t e r  part of the small can i s  700 C ,  the outer surface is only around 
60 C.  
I t  will house two small cylinders that  will encompass 
The melting furnaces are made 
The al loy 
The Data Acquisitions and Control U n i t  (DAQ2-K)  exter ior  i s  also made 
of aluminum and i t  contains the experiment control system which supervises 
the two separate metallurgical experiments. I t s  primary functions include 
measuring temperatures of the experimental vessels,  storing measured values 
for l a t e r  r eca l l ,  operating the two furnaces used i n  the experiment and 
sending experimental data to  external telemetry equipment. 
control system has two modes of operation, normal and t e s t .  The normal mode 
is used dur ing  f l i g h t  t o  run the experiments solely under control of the i n -  
ternal system. 
the experiment's parameters. 
metry equipment (located i n  Expt .  #4) once a minute v i a  a TTL se r ia l  
data port i n  (Exp. #1). 
cal data is  also routed t o  the RS232 por t .  Telemetry data consists of  an 
ident i f icat ion of the mode currently executing the current time as main- 
tained by the system and the measured values from a l l  eight thermocouples. 
These messages a re  formatted on a computer as shown below and are  terminated 
by a carriage return and l i ne  feed: 
AA T=HHMM T C l = R R  TCZ=RR TC3=RR TC4=RR TC5=RR TCG=RR TC7=RR TC8=RR 
The experiment 
The t e s t  mode is  used in the laboratory to  insert and display 
During operation of the experiment, data i s  sent t o  the external t e l e -  
If  the system i s  operating in the t e s t  mode, identi-  
Where AA i s  a two character abbreviation of the current mode, HH i s  the 
current hour i n  24 hour format, MM i s  the current minute and RR i s  the actual 
reading - a l l  in hexadecimal notation. This experiment will weigh less  than 
30 l b s .  
MARCE will provide the signal t o  s t a r t  the melting and sol idif icat ion 
process of experiment No. 1 a t  a time when about 8 hours o f  very low "g" 
operations can be expected, such as d u r i n g  a sleep period for the crew. 
that time, a signal from the GAS APC w i t h i n  the  crew compartment will t r igger  
the operation of this experiment. Subsequent operations a re  control led 
automatically and do not  need additional signals from the crew. 
A t  
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Experiment No. 2 will be conducted inside o f  an aluminum container. 
The radish seeds will be held in place by f i l t e r  paper as the growth sub-  
s t r a t e .  Gear-type pumps will i n i t i a l l y  deliver a water / fer t i l izer  solution 
t o  the seeds, and a t  the end of the mission supply a buffered formeldehde 
solution t o  stop any fur ther  growth d u r i n g  descent and disassembly a f t e r  
return. 
Operational control of the experiment will be provided by the MARCE 
radio experiment. One hour a f t e r  i n i t i a l  G #007 power-up, a control relay 
will be closed for 30 seconds and t h u s  act ivate  pump "A" which supplies 
the water / fer t i l izer  solution t o  the seeds. Prior t o  G #007 power-down 
(approximately 120 hours l a t e r )  a second control relay will close for 30 
seconds and thus act ivate  pump "B", which supplies the buffered formal- 
dehyde solution. 
Should temperatures inside the growth chamber go below 20 C ,  a small heater 
will be activated t o  maintain required tempeIatures. There will be no 
cooling provisions for temperatures above 40 C. 
an experiment operations time of 5 fu l l  days i n  o r b i t .  
micro-gravity levels are desired, b u t  10.-3 g ' s  i s  acceptable. 
periment will weigh less than 15 lbs. 
Experiment No. 3 will be conducted i n  an electrolysis  cel l  of 6 ml volume. 
The cel l  i s  made o f  Plexiglas and f i t t e d  with two small platinum electrodes. 
An optical system consists of  a 35 mm NIKON F-2 camera with a 50 mm close-up 
lens; camera auto-winder MD-3 w i t h  camera battery pack MB-1; and a small 
NIKON SB-E electronic flash.  The battery pack holds 10 AA s ize  bat ter ies  
(15 V DC)  and is  used t o  power the camera. The electronic flash holds 4 
AAA s ize  (6 F D C )  bat ter ies .  Operational control of  the experiment consists 
of  application of a 1.3 V DC precision reference supply t o  furnish the 
potenti a1 across the platinum electrodes for  nucl eatifon of crystal growth ; 
camera operation will be synchronized w i t h  the flash t o  photograph the crystals  
a t  a r a t e  of one exposure per four minutes for  24 hours. A thermistor is  
attached t o  the e lec t ro ly t ic  cell  t o  monitor the temperature fluctuations 
of the experiment's environment. The precision reference supply and a 
control timer will be furnished by MARCE. The experiment will weigh less  
than 10 lbs. 
T h i s  experiment will require a temperature of 30°C pius/minus 10°c. 
A turn-on signal as early in f l i gh t  as possible is  desired as well as 
Best available 
This ex- 
Experiment No. 4 provides power, control and on-board storage of G #007 
experiments environmental data. MARCE will acquire these data for  i n p u t  t o  
analog-to-digital converters through signal lines. A voice synthesizer 
Digital ker system will convert the experimental data i n t o  "ENGLISH LANGUAGE" 
and will modulate the transmitter 
The weight of a l l  MARCE equipment besides the battery will be about 
10 pounds. 
and 20 amp-hrs. 
A 25 pound surplus SPAR battery will provide power a t  28 V [IC 
-114- 
SUPPORT STRUCTURE 
The support structure for the G #007 experiments consists of two 
primary plates and four "bumper" assembli.es. One o f  the primary plates 
is  a round plate  which mounts to  the GAS canister t o p  l i d .  This round 
plate has a machined rib along a diameter, t o  which the second rectangular 
plate  is  bolted. This rectangular plate  divides the GAS canister volume 
i n  two equal halves along the longitudinal axis.  The bottom of the rec- 
tangular plate ,  which supports a l l  experiments, i s  supported by four 
"bumpers" contacting the inside of the canister.  Two of these "bumpers" 
are mounted on the lower corners of the rectangular plate.  The other two 
"bumpers" are mounted on l l T f i  mounts perpendicular t o  the faces o f  the 
rectangular plate.  (See Figures). 
TECHNICAL LESSONS LEARNED 
Even from the simplest of experimental ideas, there i s  much, much more 
From the i n i t i a l  ideas, t o  the design and fabrication o f  a l l  experi- 
t h a n  meets the eye. The main lesson learned was the complexity involved 
i n  preparing a simple GAS payload - i n  addition to  the tons and tons o f  paper 
work. 
ments, as well as integrating the four experiments into one functional 
package made the whole endeavor invaluable. 
For experiment No. 1, the major problem was f i n d i n g  a way to  monitor 
and s tore  the experimental parameters d u r i n g  operation. This problem 
prompted the development of  the DAQ2-K. 
For experiment Nos. 2 and 3 ,  the main problem was maintaining a constant 
temperature fo r  an extended period of time. Miniature heaters were designed 
to  f a c i l i t a t e  t h i s  problem. 
the c rys t a l ' s  growth was questionable until a modified 35 mm camera was 
acquired t o  compensate t h i s  essenti a1 requirement . 
Experiment No. 4 ' s  major hurdle was obtaining approval t o  mount an 
external antenna an the outside of the GAS canister.  
overcome. 
In a d d i t i o n ,  for  experiment No. 3 ,  recording 
Also, t h i s  problem was 
Overall, PROJECT EXPLORER has come a l o n g  way from i t s  i n i t i a l  beginning 
and has accomplished 90% o f  its original objectives. 
ACKNOWLEDGEMENT 
G #007 could not have been completed without the dedication and to ta l  
commitment of the student P.I.'s and MARCE P.I. who a l l  made gal lant  
achievements i n  preparing the i r  individual experiments. Also, thanks and 
appreciation go t o  the ca-Directors, Project Managelr, the Integration Team, 
and countless others who have contributed immensely i n  making this payload 
a huge success. 
-115- 
GAS + 007 
EXPERIMENT = 2  
FIGURE 1 
-116- 
P1 E LE CTRO N IC  
l o  O O I  0 
GAS # 007 
PROJECT EXPLORER 
0 0  
@o 
e 0 
0 
0 
0 
0 
0 
0 
0 
0 
EXPERIMENT $4 FIGURE 2 
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Project Explorer: Get Away Special #007

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