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ASMSAArkansas School for Mathematics, Sciences and the Arts
Team Name: ASMSA BESTTeam Number: 165Advisor: Nicholas Seward ([email protected])Web Address: best.asmsa.org
Table of Contents
Research Paper .......................................................................................1
Design Process ........................................................................................7
Brainstorming Approaches ...............................................10
Analytical Evaluation ..........................................................17
Offensive and Defensive Evaluation ..............................20
Fabrication and Refinement .............................................23
Safety.........................................................................................................25
Appendix
Safety Checklist ...................................................................28
Programming........................................................................30
3/8” Wood Usage.................................................................34
Safety Pictures ....................................................................36
Research Paper
1
Genetic engineering opens up windows of possibilities that could potentially reduce the
effects of deadly diseases and pests. However, genetically modifying bugs can have some
unforeseen negative effects on the environment and its inhabitants' health. Therefore, it is
imperative that genetically modified organisms go through many tests before being
released into the environment. The theme of the 2011 BEST game represents a potentially
dire situation, since the bugs that have escaped their laboratories have yet to undergo the
tests that ensure that they will not disrupt the environment. It is the teams' job to capture
the genetically engineered bugs as quickly and safely as possible so that the surrounding
environment and the community remains safe from the potential ill effects that the
modified bugs may have. In a real-world situation, it would be important for people to
handle the bugs as little as possible since they may carry a disease that could spread to the
human population. Therefore, robots seem to be the best alternative for safely and quickly
capturing these bugs.
The idea of genetic engineering can trace its roots back to Charles Darwin and his ideas of
natural selection and evolution. Genetic engineering is, in essence, human controlled
evolution. The first major experiments in the field were Gregor Mendel's experiments with
peas in which he explained the laws of genetics. Almost a century later, in 1973, DNA from
an African clawed toad was extracted and inserted into bacterial DNA. This was the first
successful genetic engineering experiment. Since then, there has been many successes in
the field, such as genetically engineered drugs, food (chymosin), Bovine Growth Hormone,
and even cloning (“History of Genetic Engineering”).
At the University of Arkansas, genetic engineering projects include a project by Professor
Daniel J. Lessner to engineer a methanogen that contains a DNA molecule that allows the
2
organism to break down esters into methane (Ford). Another project at the University of
Arkansas involves the Agricultural department genetically improving cowpea to be more
resistant to insects and herbicides (Manoharan, Khan, and Gardner) .
Molecular biologist, Stehpen Hughes has been conducting research at the USDA
Agricultural Research Service since September 2004 in an attempt to develop a a
microorganism that can be used in the fermentation process that converts renewable
materials to fuels. The traits they are trying to acquire are ones that are good for
fermentation of lignocelluosic material. To scan thousands of candidates for these traits, a
robot is being used to identify xylose-utilization genes. All of this is in an attempt to
improve the yeast that ferments xylose to ethanol. The robot is instrumental to Hughes
research because it can perform much faster and more accurately than a human could. It's
job is to create genetic libraries from copied genetic material. It uses these libraries to to
pick the best genes and then pairs them up with a corresponding protein. These new
desirable genes can then be inserted into yeasts. It would be impractical do have done all
this work without the help of a robot (McElroy).
While genetic engineering would provide exciting advances in technology, there are
potential hazards from this research. Companies that genetically engineer crops are
threatened by those that engineer insects (Jeeg). Since the crops are made to be resistant
to insects, if the insects are not an issue, the companies no longer have a product to sell. If
some genetically modified insects are able to reproduce and replace the natural population
of insects, certain transgenic traits may be spread through the population and make pest
problems worse or even create unforeseen problems (Jeeg). Genetic engineering could also
potentially allow insects to carry human diseases or to create diseases in the food that they
3
produce (Jeeg). To prevent possible problems with genetically modified organisms, there
are several precautions that scientists must take. The modified organism has to be able to
pass many tests before it can be released into the wild (“Safeguards on Genetic
Engineering”). Because of the possible negative impacts that genetically modified insects
may have on the outside world, it is important to retrieve escaped bugs before they can
cause any harm.
There are many different types of traps to catch different types of insects. Some traps
utilize pheromones to attract insects and trap them. Traps like these are often used to trap
moths (Tree). Ant traps usually involve a slow-acting poison that the ants can spread to the
rest of the colony, and, hopefully, destroy it (Tree). Since we do not want to harm the
genetically engineered specimens that we are trying to catch, the trap we use for capturing
the bugs is more like a bottle trap. Traps like these allow the specimen to crawl inside, but
not back out (Tree). These traps do not use poisons or harm the bugs they catch (Tree). To
increase the efficiency of the traps they could be attached to robots. Doing this would
allow traps to be moved to around to where the bugs are without human contact. These
robots could also utilize gene identification technology to process bugs to determine
whether they are harmful or not. Thus, bugs could also be organized and placed into
respective holding containers depending on whether or not they pose a potential threat to
the environment.
With new advances in genetic engineering, it becomes imperative that methods for
capturing and storing experiments in the event of an emergency. In some experiments, the
subjects may have the potential to harm human researchers. Robots could bridge this gap
to capture the insects instead. There hasn't been much application of this idea yet,
4
however, there is much potential. Traditional passive traps could be used in conjuncture
with robots to allow capture that doesn't harm the experiments while ensuring the safety
of researchers. These problems are addressed in this year's BEST game in which teams are
required to safely capture and transport genetically altered insects. The robot is designed
to catch the most insects and quickly transfer then to ensure safety. This theme
acknowledges potential real-life problems that could arise with as genetic engineering
develops more.
5
Work Cited
McElroy, Auduin. “A Robot Helping Hand.” Ethanol Producer Magazine. 2007. Oct 2010.
<http :// www . ethanolproducer . com / articles /3172/ a - robotic - helping - hand >
“History of Genetic Engineering.” MSPCA-Angell. 2009. Oct 2010.
<http :// support . mspca . org / site / PageServerpagename = advo _ Lab _ Animals _ History _ G
enetic _ Eng ineer >
Jeeg. “Genetically Modified Insects: What next?” Council for Responsible Genetics. 2010.
Oct 2010.
<http :// www . councilforresponsiblegenetics . org / blog / post / Genetically - Modified -
Insects - What - next . aspx >
“Safeguards on Genetic Enigeering.” Oracle ThinkQuest. Oct 2010.
<http :// library . thinkquest . org /20830/ Manipulating / Experimentation / GenEngineerin
g / dangers . htm >
Garner, J. O., M. Manoharan, and S. Khan. “Molecular Genetic Improvement of Cowpea.”
United
States Department of Agriculture. 2008. Oct 2010.
<http :// www . reeis . usda . gov / web / crisprojectpages /201084. html >
Ford, Anissa. “University of Arkansas Professor engineers methane-producing organism.”
HULIQ. 2010. Oct 2010. <http :// www . huliq . com /10178/ university - arkansas - professor -
engineers - methane - producing - organism >
Tree, Alex. “What Are the Different Types of Insect Traps?” WiseGeek. 2003. Oct 2010.
<http :// www . wisegeek . com / what - are - the - different - types - of - insect - traps . htm >
6
Design Process
7
To design a successful robot, a solid engineering process was used. This consisted of
brainstorming robot ideas, developing designs from these ideas, ranking these designs
based on their strengths and functionality, analyzing the results, choosing a robot, refining
its construction, and testing the robot to reveal flaws so that they could be repaired.
Initially, the team used their accumulative creative abilities to brainstorm possible designs.
Multiple ideas were proposed, many of which were transformed into designs. These designs
included specifics such as how the proposed robot would to operate. Each design was rated
based on potential points scored, speed, ease of control, weight, and ease of subject
containment. This helped the team decide which robot design was the best to build given
the standing time constraints. Ultimately, three final robot designs were produced. The
highest rated robot design was refined to produce the maximum number of points with
respect to a reasonable assembly time. This robot was assembled and tested for point
acquisition ability and locomotive capabilities. It went though consistent testing phases in
which the robot was analyzed and new features were added or weaknesses were
addressed. This process occurred frequently with many modifications taking place over the
8
course of the six week time constraint. Our final robot would not have the advanced
functionality it has now without the many changes that took place. Thanks to the clearly
defined design process, the robot was able to drastically increase its scoring capabilities
before the competition.
9
Brainstorming
10
After attending the BEST Kickoff Event, our team was enthused and ready to design the
best robot within our abilities. The whole team sat down and began drafting designs and
forming ideas. We scanned each sketch into a computer, which were then uploaded to our
online team folder. Team members could then go online and observe these sketches and
makes suggestions for new features and additions to be added to the robot. We found this
to be an effective way to build upon our early designs. While brainstorming, several
methods were constructed to address various aspects of the game.
Overcoming Obstacles in Front of Containment Areas
The first step was to define the problem at hand: How should the robot deliver the bugs to
the scoring bins? One of the most hurdles our robot needed to overcome in order to score
was navigating through or reaching over the 3 ft x 4 ft space in front of each scoring zone.
The team decided that some viable options were to design a robot that could drive across
or over the obstacle area, design a robot that could reach entirely over the 3 ft length, or
design a robot that could perform a combination of the two. If the robot was designed to
simply drive over the obstacles, it would have required a four-wheel drive system,large
wheels in order to be able to pass over obstacles, and some sort of dump truck design, such
as a scoop on the front or a bin on the back, to transport and score the gathered bugs.
Another proposed idea was to design a robot to reach over the obstacles instead of driving
over them. This eliminated the risk of the robot getting stuck in the obstacles, but the arm
would have to be designed strong enough to reach across the entire three feet and retract
without unbalancing the robot. To gather the bugs, a trap with a self-contained holding bin
could be attached to the end of the arm. One arm design suggested was an arm made of
two pieces of PVC, a smaller tube inside a larger tube. A motor would wind up a string
attached to the inner tube, and as the string wound up the inner tube would be extended.
11
Another proposed design for the arm was folding arm with a parallel linkage to keep the
upper member parallel. It would be made of three separate legs, two of which were parallel
to each other with pivot points on the robot and the top arm. This would serve to keep the
upper member parallel to the ground. In order to maximize the point acquisition ability of
the robot, the team proceeded to analyze each design.
Obtaining and Scoring Bugs
The team brainstormed several different trap designs to capture a variety of bugs. One idea
was to use an adjustable, articulate scoop that would pick up termites and transport them
to a scoring bin, then dump them. The scoop would also be used to pick up and transport
food into scoring bins. Another proposed idea was a modified scoop with channels. This was
a passive design that was simply set into the cockroach area. The cockroaches would
wander into the channels and be unable to turn around to escape. After a time, the scoop
was lifted and then dumped into a scoring bin. A third idea was a three-pronged “hand” that
could be used to clasp a fly. The “opened” hand would be maneuvered under a fly, the
“closed” when it could grasp the fly. The clasped hand would bring the fly down, then
transport the fly and drop it into a scoring area.
Proposed Locomotion Designs
The first design proposed was the classic four-wheel-drive system. This design involved two
sets of driving wheels each controlled by a large motor. While the preliminary design
appeared well on paper, the point that it would take much more power to drive the two
extra wheels was brought up and the pros and cons were discussed. The cons greatly
outweighed the pros in this case and the second design was proposed.
12
The second locomotion design was a simplification of the first in that there were two drive
wheels on the front sides instead of four drive wheels equally spaced along the robot sides.
In this design however, there was an extra wheel at the back of the robot to hold the rear
up. This design not only appeared to work as well as the first locomotion design but in at
least one case, it was considered to do better. In the case of turning, this two wheel design
offered more consistent turning by limiting the number of focal points with the ground and
thereby decreasing the variation in turn times caused by the battery level. This design
dominated the minds of the team and was ultimately selected as the locomotion design of
choice.
The third and final locomotion design was an entirely new concept, the Hoeken’s Linkage.
This design involved two legs that moved by varying the sizes of circular movements to the
extent that the resulting motion lifted the leg, pushed it forward, and set it down.
Although this design seemed to work well in testing, it was decided by the team that this
design was overly complicated and had too many points of failure; this reason was realized
during the final test run when the glue-joints broke on one of the legs. Because of this
crucial flaw, this design was not selected but it was concluded that with a little more
thought, this leg movement idea may be promising in the future.
Proposed Designs
The first design proposed was created in order to solely capture cockroaches. The robot
includes an extendable folding arm with an articulated cockroach trap on the end of the
arm. It is driven by two modular wheel assemblies, placed on each side. An omni-wheel
would be placed on the rear of the robot to facilitate mobility of the robot. The cockroach
trap would be lifted up and down using the brake cable and either a servo or small motor.
13
During each game, the robot would place its trap in the cockroach cabinet and allow the
cockroaches to accumulate in it. Then after a certain period of time the driver would pull
the arm of the cabinet, drive the robot to the wooden pile containment area, extend the
arm over the obstacle, and dump the cockroaches in the scoring zone.
Fig. 1: First draft of robot design, scissor arm, cockroach trap, two wheel drive.
The second design was created with the collection of termites and possibly food in mind.
This design includes a four wheel drive locomotion system driven by large motors mounted
to the bottom of the robot’s base, a large scoop on the front of the robot that pivots in
order to pick up termites and food. When this robot is in play it will scoop termites and
deposit them into the wooden steps containment area. The four wheel drive system will
allow the robot to overcome the steps and place the termites in the scoring zone.
14
Fig. 2: Design number 2, four wheel drive, tiltable scoop.
The third design for the robot focused on catching flies. It would include a PVC extendable
arm, a claw for grasping flies, and two wheel drive with an omni-wheel. The arm would be
powered by a small motor that would rotate a pulley with string on it to pull the inner PVC
pipe out. The robot would score by opening the cabinet door, grasping flies, then
depositing them one at a time in the wood pile scoring area.
15
F
Fig. 3: Two wheel drive with omni-wheel, PVC extendable arm, and fly-grabbing claw.
16
Analytical Evaluation
17
To evaluate the different robot designs, the pros and cons of each design were examined
and then applied to a table showing each designs overall usefulness. This was a logical step
in selecting the best choice for the robot as the pros and cons could be quantified and
totaled. The robots were rated on the number of points scored, the speed of the robot,
how easy it was to control, the weight of the robot and finally how easy it is to replace the
various of parts on the robot. The final table is displayed below. The scores and arranged
from a “+” which is worth a positive point, a “-” which is worth a negative point and finally a
“0” which is neutral and denotes no points.
Design Number
Points Scored
Speed Ease of Control
Weight Ease of Subject Containment
Total
#1 + + + + + 5
#2 0 + 0 + 0 2
#3 + + - 0 - 0
This table shows the total for each of the designs. The first design was the obvious winner
with a score of five. It received a plus on the first category because, while it was able to only
go after low point targets, it was able to use the highest multiplier containment zone. The
second design got a neutral here since it could only go for a basic zone without the reach of
the first of third designs but it was able to gain a medium point target. It also takes longer
to collect the targets in this design. Finally the third design also gained a plus since it was
not only able to get the highest point target but it also had the reach to use the highest
point containment zone.
The speed category was positive across the board as it was planned to use a modular
system with all three designs that would give them all the same speed. In the control
category the first design received a plus. Control of the first robot only requires the ability
to land the trap on the bug field and then drop them into the containment zone. The
18
second design requires a slightly higher amount of control as scooping is slightly more
difficult and requires more time. The second design got a zero. The third design was given a
minus on control as it required almost perfect precision to get the claw around the fly and
then to drop it into the containment zone.
In the weight category both designs one and two received “+”s while three got a “-”. Design
one was able to use it's weight to counter balance the arm with the trap. The second design
had a lower weight and didn't need to counterbalance anything. The third design had a long
arm but low weight creating an issue with balance.
Finally they were rated on how easy it was to contain the subject once captured and during
transportation. The first design uses a trap that contains its subjects permanently until
ready to drop out and so gained a “+”. The second design uses an open scoop to collect
subjects creating a small chance of falling but no real danger. The final design however has
a higher chance of dropping the subject and from a very high place possibly losing us points
or getting us disqualified.
19
Offensive and Defensive Strategies
20
Before the robot was designed, the team first discussed different ideas for maximum
points, feasibility, and difficulty level. When the different point combinations were
considered, all three types of bugs, food, and separation of the experiments in the different
containment centers were taken into account. Three types of scenarios were evaluated in
the final brainstorming prior to robot construction.
All Flies
The first strategy was to find the maximum points obtainable by capturing every fly and
returning them to the containment centers. This strategy did not include obtaining food, or
sorting the bugs, it did however including putting all the flies into the wood pile
containment center. The point total of this strategy was calculated to be 510 points.
However, this strategy was quickly abandoned because it was deemed to be inefficient.
First of all, to get the 510 points, all flies would have to be captured by our team and be
placed into the wood pile containment area. This is not feasible, considering that other
teams would be seeking the same flies with their robots. Secondly, the main flaw of the fly
catching idea was to collect the flies with a claw-like apparatus. This would require the
robot to grab each of them one by one, which would consume much of the competition
time. Finally, building a claw seemed a terribly difficult engineering task that could not be
accomplished in just six weeks.
One of Every Bug, Plus Food
The second strategy involved obtaining only one of each bug and separating them into the
three containment fields along with a piece of food. With this strategy, cockroaches would
be placed in the stair containment area, termites would be placed in the pipe containment
21
area, and flies would be placed in the woodpile containment area. The total calculated
points for this strategy were determined to be 239.
Although this strategy had its advantages, such as being relatively easy to complete within
the alloted competition time, it was not chosen for several reasons. The main reason being
it would be an engineering nightmare to design a robot that could be that versatile in the
competition.
All Cockroaches in One Field
The final strategy was to capture most of the cockroaches as fast a possible and dump them
into the wood containment area without food. The total points possible with this strategy is
350, which is only possible if all twelve cockroaches were captured. This was to be
accomplished with a cockroach catching apparatus attached to the extendable arm of the
robot.
The final strategy was chosen because it was possible with only an efficient and specialized
building job. Most of the competition time would be spent waiting for the trap to capture
cockroaches. This simple strategy accomplished the highest point total and was the main
focus of the overall robot design.
22
Fabrication and Refinement
23
Before the parts were actually made, our team sat down and discussed possible ideas of the
look and design of the robot. Through discussion, sketching, and prototyping a design was
produced that contained all the aspects of this years game. The robot for the local hub
competition was fabricated using an automated mill. The parts needed were drawn in Auto
CAD and then put into CAM BAM to produce G-Code that was then fed to the CNC mill.
These parts were cut mostly out of the three-eighths wooded sheets. The “claw” on the end
of our arm was fabricated by heating PVC and molding it to our required specifications. The
motor mounts were drawn first in CAD, then by using the band saw, they were cut out and
drilled.
After the first generation, the arm was obviously very ill supported as it swayed from side
to side when the robot turned. This issue was fixed by adding three supporting pieces of
wood along the arm. Although this modification fixed the swaying problem, the arm was
now too heavy to lift with one single motor. A bungee cord was attached onto the end of
the arm and to the base, which easily fixed this problem. Due to lack of material, the wheels
were re-milled to be one-quarter in width, which also helped conserve weight.
24
Safety
25
Safety is a top priority at ASMSA Robotics Inc. We cannot afford to lose our valuable team
members due to injury or worse. To prevent any type of injuries, we follow strict safety
rules while working in the wood shop or with the robot. In an unforeseen circumstance, it is
important that we always have safety on our mind so that if there is not a rule that applies
in the situation, we can still be safe.
We make sure that we wear proper safety equipment such as safety goggles and wood
shop appropriate clothing. Only close-toed shoes are allowed and no dangling clothing is to
be worn. There must be be nothing hanging down in front of the operator of machinery and
workers with long hair must keep their hair tied back and out of the way. When operating
machinery, we make sure that we are a safe distance away from the dangerous machines.
No one is to be within close range of the machine operator as this could lead to distractions
and possible injuries. We also make sure that no horseplay takes place in the lab or wood
shop as this could lead to potential injuries or damage to equipment. While in the wood
shop, food and drink are not allowed. These could spill on equipment or be contaminated
by the wood or metal shavings that are produced from the machines.
26
Appendix
27
Safety Checklist
28
Work Shop Safety Checklist and Manual
Proper Safety EquipmentGogglesGlovesClose-Toed ShoesClose Fitting ClothingTied-back Hair
While Operating MachineryStanding a safe distance awayStanding away from operatorTurn off machine to adjustWear appropriate clothing; Including Ear Protection
Before Leaving the AreaLeave the area cleaner than foundSweep all the floorsPut up all unused toolsShut off unnecessary lights
OtherNever work aloneAlways use the proper toolsNo HorseplayNo RunningNo FoodNo DrinkNo TextingAlways THINK before you act
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Programming
30
#pragma config(Motor, port2, LeftMotor, tmotorNormal, openLoop) #pragma config(Motor, port4, Trap, tmotorNormal, openLoop) #pragma config(Motor, port7, Arm, tmotorNormal, openLoop, reversed) #pragma config(Motor, port9, RightMotor, tmotorNormal, openLoop) //*!!Code automatically generated by 'ROBOTC' configuration wizard !!*//
//Global Variables int threshold = 40; // Used to cancel 'noise' of low values int speed_mod = 3; // Used to modify output for singl_ctrl
int ctrl_type = 3; //1 = dual stick, 2 = single stick, 3 = halo
int right_ch1 = 0; //update 'right_ch1' to new current reading int right_ch2 = 0; //update 'right_ch2' to new current reading int left_ch3 = 0; //update 'left_ch3' to new current reading int left_ch4 = 0; //update 'left_ch4' to new current reading //
void control(); void dualS_control(); void singl_control(); void halo_control();
task arm() //arm task kept out of main task so arm can be controlled while driving { while (1 == 1) {
if (vexRT(Btn6U) == 1 ) //if up button on right shoulder is pressed { //move the arms up motor[Arm] = 127; } else if(vexRT(Btn6D) == 1 ) //if down button on right shoulder is pressed { //move the arms down motor[Arm] = 127; } else { motor[Arm] = 0; //if neither right shoulder button pressed, do nothing with motor }
if (vexRT(Btn5U) == 1 ) //if up button on right shoulder is pressed { //move the arms up motor[Trap] = 127; } else if(vexRT(Btn5D) == 1 ) //if down button on right shoulder is pressed { //move the arms down motor[Trap] = 127; } else { motor[Trap] = 0;
//if neither right shoulder button pressed, do nothing with motor }
31
} }
task main() {
StartTask(arm); //begins 'arms' task
while(1 == 1) { control(); //main subroutine, control scheme switching and motor control wait1Msec(20); // the VEXnet controller updates every 15ms or so } }
void control() { right_ch1 = vexRT[Ch1]; //update 'right_ch1' to new current reading right_ch2 = vexRT[Ch2]; //update 'right_ch2' to new current reading left_ch3 = vexRT[Ch3]; //update 'left_ch3' to new current reading left_ch4 = vexRT[Ch4]; //update 'left_ch4' to new current reading
if (vexRT(Btn7L) == 1) //dual joystick control ctrl_type = 1;
if (vexRT(Btn7D) == 1) //single joystick control ctrl_type = 2;
if (vexRT(Btn7R) == 1) //halo control ctrl_type = 3;
//if up button on right dir pad pressed then activate speed modifier if (vexRT(Btn7U) == 1)
speed_mod = 1; else //otherwise leave it alone speed_mod = 3;
switch (ctrl_type) //use different control mode depending on control type
{ case 1: dualS_control(); break;
case 2: singl_control(); break;
case 3: halo_control(); break;
32
default: halo_control();
}
}
void dualS_control() //dual stick control for bot { //are either of them over the 'noise' threshold? if ( (abs(left_ch3) > threshold ) || ( abs(right_ch2) > threshold) ) { motor[LeftMotor] = left_ch3; motor[RightMotor] = right_ch2; } //NO make no changes//2 motor = 0's necessary bc one channel may be active and other not then else { //other motor won't update motor[LeftMotor] = 0; motor[RightMotor] = 0; } }
void singl_control() //single stick control for bot { //are either of them over the 'noise' threshold? if( (abs(right_ch1) > threshold) || (abs(right_ch2) > threshold) ) { motor[LeftMotor] = ((right_ch2+right_ch1)/2*speed_mod); motor[RightMotor] = ((right_ch2right_ch1)/2*speed_mod); } else //NO make no changes. { motor[LeftMotor] = 0; motor[RightMotor] = 0; } }
void halo_control() //halo stick control for bot { //are either of them over the 'noise' threshold? if ( (abs(left_ch3) > threshold ) || ( abs(right_ch1) > threshold) ) { motor[LeftMotor] = (left_ch3+right_ch1); motor[RightMotor] = (left_ch3right_ch1); } //NO make no changes//2 motor = 0's necessary bc one channel may be active and other not then else { //other motor won't update motor[LeftMotor] = 0; motor[RightMotor] = 0; } }
33
3/8” Wood Usage
34
35
Safety Pictures
36