Mike and Joe with Ramming Speed at BattleBots in May '01
11/3/01
I'm on the plane
headed out to San Francisco. Perfect time to catch up on a few of the
pictures I need to get posted here. Here's what Ramming Speed looks like
now:
Here's the crate when it shipped:
As you can see in the last picture, the
crate ended up weighing 125lbs. Wouldn't want to bring it on a plane if I
could, so it was shipped via truck.
A lot changed since the first design.
First, I shortened the wheel base by about two inches. I switched to
Performa wheels instead of the alumium ones.
7/8/01
I've developed a solution for the
spindle, utilizing the stock spindle. We'll find out in testing if it
really works. I've also developed a solution to allow easy replacement of
the front wheels. I've almost got something ready for the back wheels,
which are a bit more difficult.
The new season (Season 3) of BattleBots starts this
Tuesday (7/10) on Comedy Central. Watch for me in the crowd! I'm going
through all my recordings and seeing what episodes I have, and which I'm
missing. For those of you that are interested, here is the official Episode
Guide, describing the fights in each episode for Seasons 1 & 2.
I'm also trying to piece together the Season 3
Episode Guide as I here about matches...
6/4/01
Ramming Speed should be arriving
home soon, and I've got ideas on how I can improve it, mainly the spindles
of course. I'm also toying with a few other bot ideas. Don't want to
reveal them yet, but the code names are: Woody, Trojan, and Sojourner.
I'll most likely build one of these to compete, most likely Trojan, and
will be attempting to get sponsorship. Would you like to be a part of the
excitement that is combat robotics? Drop us a line at info@clobberbots.com.
5/31/01
Posted the pictures I took on a
special "BattleBots SF01"
page. 99 pictures, enjoy! Note: some of the picture include damage done to
bots during fights, and may hint at fight outcomes (though some are
misleading). If you don't want to know, you may not want to look at these
pictures.
5/30/01
I'm back. The BattleBots trip was
excellent. Approximately 350 robots actually ended up competing. Most of
the people there were great, with lots of sharing and comradery. I'll be
posting pictures shortly, but seeing close to 500 robots spread out on
tables in a room is quite an awesome sight. I didn't see much of San
Francisco, but from what I did see, I wasn't to impressed. The
architecture sucks. Homeless on street corners. No parking. Crowded. Just
didn't like the overall 'vibe'.
So anyway, you want to know how I did. I'm under a
non-disclosure agreement, so I have to be careful about what I disclose.
In my case, I doubt Comedy Central will mind me disclosing how I did,
since I lost my first fight, before the filming started. Yes, I'm
disappointed as well, but the trip was still worth it. What happened? If
you can believe it, I had to much power. The buzzer sounded and my
opponent and I both charged across the box, and neither of us flinched,
resulting in a spectacular hit in the middle of the box. We both survived,
and I began pushing my opponent, an underpowered wedge, around a bit. As
we fought, it seemed I was loosing control, as Ramming Speed wasn't doing
what I was asking. Seemed like a transmitter problem. It got to the point
where I could hardly move around, and it appeared that only one back wheel
was turning. My opponent still had trouble moving me around. The match
went the distance, and was decided in a 25-20 decision, in favor of my
opponent.
After getting to the pits, I opened the cover and found
that three of the four spindles had sheared off. Yes, this had happened
once before on one spindle, and I had hoped it was a fluke, apparently it
wasn't. It appears that because I was practicing on a relatively slick
surface (like a basement floor), I wasn't getting great traction, and the
wheels spun a bit, restricting the amount of force on the spindles. In the
box, the surface is painted with a rubber traction paint. On top of that,
I borrowed some traction compound to put on my tires. This resulted in
great traction, putting much more strain on the spindles than they had
seen before. The spindles were made of 304 Stainless Steel, which I had
ground the end of to fit into the gear box. I believe the heat of the
grinding annealed (softened) the metal to the point that the torque the
motors put out overcame the strength of the metal, resulting in
shearing.
What now? I will return. It's my opinion that had the
spindles not sheared, I could have won my first four fights (based on the
fights that actually took place). I don't think I could have won it all.
Some of the veterans are excellent drivers, and even if my bot was better
than theirs, with the arena hazards running, they could have out driven
me. My summer project is to get Ramming Speed up to snuff, and get in lots
of practice driving. I also have lots of ideas for other robots that you
will be hearing about in the near future.
From what I hear, these fights will be aired beginning
July 10th on Comedy Central. You'll definitely want to watch, as this
season produced some of the best fights yet. I believe BattleBots will
need to strengthen the box for the next competition, as it was severely
tested this time. Stay tuned for pictures...
5/21/01
Well, this is it! I've got a
suitcase full of parts, and a duffle bag full of tools. Cloths get packed
tonight (mostly jeans and special 'Ramming Speed' T-Shirts we had made).
Sounds like the weather can be pretty unpredictable, but will definitely
include cool, damp and foggy. Sounds like a weather system may push in
from the desert that may raise the temps into the 90's, then ocean winds
will move in dropping the temps. The advise is to bring a little of
everything. I'll try to check in on my e-mail occasionally, so if you need
to get a hold of me, that would be the best method. I'll be bound by a
non-disclosure agreement when I return, but will share what I can,
hopefully including many pictures and movies of the pits. Till then...
5/18/01
Ramming Speed is off to San
Francisco! I loaded it personally onto a truck this morning. It will be
arriving on Monday the 21st, when some representatives from the East Coast
Robotic Association (ECRA) will sign for it and move it to my pit table.
This will save me the hassle of trying to get it on the plane. I've
started gathering all the tools and parts I want to take so I can figure
out how much luggage I'm going to need. Seems like I need the entire shop!
Not sure how I'm going to get the table saw on the plane.
BattleBots has stated that food will be catered (free!),
so this should help cut down on costs. Parking will also be free for competitors.
The prize for lightweights is $4000 and a Lincoln Electric SP 125 Welding
Machine. Their are 160 lightweights registered. I'm guessing that after
those that didn't get finished in time, can't make it, or don't pass
inspection their will be about 125 actually fighting. If this is the case,
I think I'll only have to win two or three fights to make it to the 'TV'
rounds (those aired by Comedy Central). Seven rounds total (128, 64, 32,
16, 8, 4, 2).
5/11/01
Well, we're getting close to
robot fighting time! We've been excepted, got the plane tickets, hotel and
truck reservations. We leave at 6:20am on the 22nd, and we'll be back in
town about 8:30am on the 29th.
The robot is doing well. Did a stress test a few days
ago by driving it full speed into a concrete column. After the fourth or
fifth time one of the wheels stopped driving. Took it home and found that
one of the fans on the Victor 883's actually broke off it's supports,
though it continued running. I removed the one for the motor that stopped,
and after hooking it up on the bench, it seemed to work fine. I've ordered
two extras, one to replace the broken fan until it can be
repaired/exchanged, the other to replace the one that went out if I can't
figure out why it went out. Structurally, everything held up fine, with
only slight damage to the leading edge of the angle iron. I took one of
the runs into the column at an angle, so the outside edge by the wheel hit
first. Didn't bend at all.
I rebuilt all the battery packs so that I now have six
20 cell, 24v, 2.4ah packs. This will provide three two pack setups. Not
required for fighting since they can be charged in 30 minutes, but nice
for testing.
I got a couple of the Colson wheels that most of the competitors
use so I could test them, and possibly switch over if they seemed better
than what I've got. Out of the box they are stickier that what I have, and
switching to four of them, in place of the four I currently have in the
front would save 1 pound. I picked up some liquid that increases traction
by softening the rubber. I tried this on the Colson's and on the wheels I
currently am running. My wheels ended up being stickier! I still need to
play with the Colsons a bit more, but after cleaning and softening my
wheels they have some wicked grip, easily justifying the extra pound of
weight.
I built a case to put it in, and I've been putting
together a list of all the tools, materials, and spares that I will need.
I'm pretty much going to have to ship my entire shop to San Francisco!
Team member Mike has come up with a logo for Ramming Speed, and is getting
T-Shirts make. He's also ordered vinyl decals that we can apply to the top
and bottom of the robot. Last I weighed it, we were at 58.5 lbs. The limit
is 58.9. I haven't changed anything that should affect weight, so I'm
going to try an drop just a little more for a margin of safety. I'm also
going to take it to UPS and weigh it there for comparison. Don't want to
be drilling random holes in it in SF just to qualify for my weight class!
Many details have changed on the bot since the build
reports I put together. After the event I'll probably redo the website to
show the 'as built', and try to explain how and why things changed, just
not enough time for now. I'll try to get some more pictures up on Monday,
and see if Mike can digitize some more film (like the bot hitting a
concrete column).
4/30/01
I just added updates from the
past couple weeks. You'll definitely want to go down and see what happened
on the 18th, and also give the movies a try. They're probably a bit large
for those of you with modems. We'll try to digitize more of our film, and
develop some smaller snippets of the best moments.
I did a test bench run with a 40 cell battery pack. Ran strong for 2 minutes 40 seconds, then the tone
changed slightly, but it still ran strong till about 5 minutes. It then
began slowing down with the first wheel stopping a little over 8 minutes.
All four wheels were stopped at around 9 minutes. Fast charging the
batteries takes 31 minutes (2 AstroFlight 112D charging 2 20 cell packs)
providing a total of 5AH.
I'll be test driving tonight, doing a simulated fight by
kicking but on a large stump, and see how long I last. I'm hoping the 40
cell pack is enough since reducing from 60 to 40 saves almost 3 pounds.
With the smaller battery packs, I am currently at 58.5 lbs, with a limit
of 58.9 lbs.
P.S. Just got back from the test. AWESOME! Ran strong
for 4 minutes. Really started to taper off after 5 minutes. I pushed it
pretty hard, and the stump paid dearly. Everything held together quite
well, no mechanical or electrical failures. The batteries get pretty hot,
but I believe that is to be expected considering the rate of output. The
smooth floor of our secret testing facility has been generous to the
rubber on the wheels. We'll get much better traction (though it's not bad
now), and more wear, in the battlebox. I'll be testing again tomorrow, and
making adjustments to the transmitter to raise the curve for speed output,
so I can get more control at low speed, yet pushing the levers all the way
still yields full output.
4/25/01
Many improvements on the bot
since the fire. After all the work I did on the gearboxes, two still broke
loose. I figured out a way that HAS to work now. I created a piece of
aluminum that slides onto the ribs of the gearbox, and locks against the
motor next to it. The only way the gearbox can move now is if the case
breaks (please no). I got rid of the temporary zip ties on the front
wheels and tapped holes in the aluminum wheels for 2" stainless
steel screws. These wheels shouldn't be coming apart any time soon. I also
needed a way to hold the wheels on the axle.
Instead of the heavy compression collar I started with, I tapped holes
into the axle and drove screws through the hub. The chains stretch a lot,
and I've got no built in way to tension them. I also don't have much space
for adding idler sprockets. I decided to use pieces of plastic
cutting board to create a pocket for the chain to ride in. It is close
enough to the sprockets that the chain cannot come off, yet slippery and
durable enough that the chain hitting it won't cause much damage. Finally,
the electrical switch. I've changed the electrical system to use two 24v,
2.4AH battery packs. They need to be separate to charge, but together to
run the bot, so the switch can't be a simple two terminal on/off switch.
It also has to be easily accessible from the outside should one of the
crewbots need to turn it off in an emergency. I've been scratching my head
for weeks over this one, but finally developed something that appears to
work. The switch consists of two pieces of copper, one hooked to each
battery and charging port. Their is then a rotating piece in the middle
that connects to the main line to the speed controllers. When the
rotatiing piece is turned, it connects all three circuits. Rotate it
another 90 degrees, and it disconnects the circuits. The middle piece is
rotated by turning it's shaft with a 1/4" socket driver. I'm using a
fancy flashlight/screwdriver meant for interchangeable bits. I've also
included a screwdriver slot in case their's not a 1/4" driver handy.
Here's some pictures:
Movies! Here's a rather large
(11MB) mpeg file of the christening. Here's a
2MB mpeg of a little spin action...
4/18/01
FIRE!!! We test
drove Ramming Speed again yesterday, and the first set of batteries
went pretty well. I was able to drive in a circle (not as easy as it
sounds), and push a large piece of wood around. When the batteries died, I
swapped in the second set of batteries. At this point, the video camera
died. I started driving around, and rammed the log a few times, and ended
up fishtailing the back end into the log. A large spark erupted from the
open battery compartment. As we approached the bot, smoke started to come
out, and then fire erupted. I stomped the small flames with my shoe, and
you could see the insulation coming off some of the wires. ClobberClub
member James and I were reaching in grabbing at wires trying to disconnect
stuff as the wires started to become bright orange. I was able to yank the
back battery pack out, and luckily James found a pliers so we could start
ripping the front pack out. A friend of ClobberClub
member Dan was standing by with a fire extinguisher. The room was full of
toxic smoke, which took over 5 hours to clear.
The bot is OK. Why did this happen? I didn't give the
electrical system enough respect, and one of the battery packs shorted
out. The damage was limited to wiring
near the batteries, and around half-a-dozen cells. Seems strange, but the
fire was probably a good thing. I've now gained some respect for the
electrical system and what it can do, and have taken many more precautions
to protect it. It also happened early enough that their was time to
recoup, and much of the internal design is now better laid out.
Since I had everything apart, I figured now was as good
a time as any to lighten the aluminum structure. I marked out the areas
that could be lightened without loosing much strength on the inner,
and outer structural elements. I then
drilled out a grid of 1/4" holes, which made quite
a mess. Here's the 4 pieces after
the holes were drilled, and I cleaned them up with a random orbital sander
with 150 grit.
Finally, some pictures of the bot reassembled and
charging:
Did another test run on 4/12 and
it didn't go to well. Two more gearboxes
came loose, cutting the run short. I also cut
myself on some shielding, so the Injury
page has been updated. I've had to completely disassemble the bot to
resolve this issue. At first, I thought I'd have to construct a new
structure to allow more room for mounting things better, but I've come up
with a different idea. I'm using 3500psi epoxy to join the metal cap for
the gearbox to the plastic shell of the gearbox. I'm then taping holes in
the metal cap to secure them securely to the aluminum structure.
4/11/01
We did the christening
and shake
down run yesterday. The speed is good, any faster and it would be difficult
to control. The right side drove faster than the left, so it was hard to
steer. I'll need to make adjustments at the transmitter to compensate.
Since the bot is not waterproof (I don't
even have the top armor on) I couldn't break a bottle to crison the
bot, so I drove it through a pyramid of empty beer cans. Team
Clobber member Mike did filming, and Clobber
Club member Dan heckled from the sidelines. Here
we are together.
4/08/01
It runs! I got the electrical
system hooked up, including a charging
system that allows my battery chargers
to connect without having to open the cover. I did some bench
tests with the robot up on blocks.
Everything seems to run OK. Chains flex a bit, but didn't come off. I'm
not making the holes in the structure yet for some of the wiring, so It is
currently just going over the top of the structure, which means I can't
close the top lids. Once I was happy, I set it on the floor of the
shop for a short drive. I first bumped it up against my workbench, which
probably weighs around 200lbs. I was able to push
it a short distance (notice the rubber marks left on the
floor)! I
bumped up against the door to the shop, which left a little mark, but then
when I turned around, I got a little carried away and put a big
hole in the door. We'll be taking Ramming Speed to our secret testing
grounds so I can see what it can really do. I hope to capture some video,
so stay tuned...
3/28/01
Finished making four new spindles
by grinding the ends of some 1/2" stainless steel shafts. I wrapped
the end of the shafts with tape and marked them. I then used a Dremel
to grind away the excess so it will fit
into the end of the gearbox. Here are the four
finished spindles. Figured out the timer on my camera. Here I
am in my shop. I worked at getting the fail-safe mode to work on my
transmitter, but had some problems. Kitty
took a look at it and had it working in a couple minutes. Notice the
smirk, Kitty can be pretty smug at times...
3/26/01
I've been telling everyone I'll
have this thing running by April 1st. That may be a bit of an April fools
joke. I'm going to keep trying, but I've still got a lot to do, and I've
been working my ass off. Got a huge blister
(about an inch long) on my thumb from filing excess epoxy for four hours
on Sunday. More work tonight didn't help any, but it doesn't hurt yet.
Probably won't be pleasant when it breaks. I'll probably have to wrap it
so I can keep working.
Made hotel reservations today, and reserved a truck. ClobberClub
members Mike and Dan are both definitely attending. We'll be staying at
the TravelLodge
by the Bay, only a few blocks from Fort Mason. Got a decent discount
on our vehicle rental through the hotel reservation. $194 for a 7 day
rental on a Blazer from Avis! Should be
big enough to haul all of our stuff.
Here's some pictures of the progress:
Lots to talk about. I've been
putting in lots of hours trying to get this thing running. The application
form has been submitted. From what I'm hearing, their are already 400
submissions, which is much more than last time. Clobber
Club member Mike has been promoted to a full Team
Clobber member. He's wasted no time in coming up with a new name for
the current but: Ramming Speed. This bot is way to tight weight wise, so
the previous ideas wouldn't work. Ramming Speed is a catchy name, with
history, that describes the function of this bot. We've got some ideas for
imagery that I'll show soon.
So, pictures of the progress. First, I needed to devise a way to attach
the angle iron pieces to the aluminum structural pieces. I did this by drilling
holes into the aluminum, then creating a
slot to slide a stainless steel nut into. I then tread 3/16"
stainless steel flat-head bolts into this. Here's the structure
bolted together. Here it is with the motors
installed. Here it is with the wheels
and bearings installed. I then started with the armor. I'm using
1/8" Aluminum
tread for most of the armor, and 1/4" Lexan for the rest.
Here's the armor for one side of the
bot. A steel piano hinge connects to the tread and Lexan with steel rivots. Here's the back side. Here's the armor
on the bot after drilling the holes to hold it down with 3/16"
Stainless Steel bolts. Here's what it looks like with the panels
tilted up for access.
I did some testing with the Lexan, to see how strong it is. If you're not
familiar with Lexan, it's like a very tough plastic used in 'bulletproof
glass'. Here you can see the flexibility,
it is rather stiff, but it bends before it breaks. I then supported
a small scrap piece in my WorkMate, and had at with my hammer.
Swinging as hard as I could resulted in the piece simply bouncing across
the shop (and almost hurting myself a few times). Finally, on about the
8th swing, I got it to break. I repeated
the test on another piece, but was unable to break that one after about a
dozen swings (even with the claw side of the hammer). It's no good against
saws and drills, which cut it easily, but it's tough stuff when it comes
to impacts!
3/18/01
Finished the aluminum structural
elements. Working out better than I thought. I also got a picture of the blister
on my lip.
3/16/01
I suppose I should show some
updated renderings of what this thing is looking like. Here
it is with the armor, note that the pink material is Lexan, which is
actually transparent. Here it is without
the armor. Here are the 3/8" aluminum
structural pieces I began working on yesterday. Man, I got a blister
on my lip (no not Herpies) from a hot piece of aluminum landing on it
while cutting with the cutoff wheel. Can't seem to get a good picture of
it to add to the Injuries page though. Wicked
stuff!
3/15/01
Picked up the structural metal
yesterday from Metal Express in
Waukesha. Since I've got a wood shop, and not many metal tools, I'll be
continuing my half-assing methods of working metal. I'm starting with the
3/8" pieces of aluminum that the main structure is comprised of. I
used a 2 1/8" hole saw in the drill
press to cut the holes for the motors. This was a little to small, so I
had to file and sand a bit to get it to
fit perfectly. I used a 3/4" hole saw to create the holes
that the gearbox fits in (also required filing). To cut the 45
degree angles in the aluminum plates I used a cut-off
wheel in my table saw. I used my panel
cutting jig and a huge triangle from my architecture school days to
hold it at the right angle. Feed rate is about 1/8" per second.
Aluminum get really hot (duct tape began
melting off), and hot pieces fly off all over, including your skin, hair,
etc. Best to cover up what you can. For the odd angles, I tried my saber
saw with a metal cutting blade. I found that an 18 tooth per inch
blade worked reasonably well if you oil the blade while cutting (feed rate
approx. 1/16" per second). Here's what the two
inner aluminum structural pieces look like.
3/13/01
Well, here's what the prototype
ended up looking like. Here's a better view of what the drive
train looks like. I found out pretty quickly that the wood prototype
won't be drivable. I can't mount the motors sufficiently, and they spin in
their mounts. I also found that my spindles aren't going to work, one of
them loosened up (the brass tube started spinning on the spindle threads).
I made up a couple from some 1/2" stainless shaft. I'll need to do a better
job, but this is the jist of what it
looks like.
3/10/01
I'm putting together a new
prototype that I can use to test drive with. I'm close to seeing this
thing run! You can begin to see how tight this package is in this
picture. I had to use flat braid cable to get my power from one end to
the other through the tiny gaps between the motors.
3/7/01
I will be going to San Francisco!
Then next competition is at Fort Mason in San Francisco from May 22nd
through May 28th. Clobber Club members Dan
and Mike will likely be in attendance. The name and appearance of
Bundle of Joy will be changing shortly. I don't have the weight to spare
on some of the ideas I had earlier, so this bot will be purely functional.
I laid out the electrical system. I got
an ammeter that showed that generally, I was topping out at around 30
amps per motor with no load. I saw some peaks though, with the highest
at almost 100 amps. I ordered two more
speed controllers as I am worried two motors on one controller may release
the magic smoke from them. I added a DC
converter so my 5v receiver could run off the main 24v batteries,
instead of needing their own separate battery pack. I then duct taped two
motors to a piece of wood (so they wouldn't fly around the room) and
hooked everything up. A few minor adjustments, and I was controlling the
motors from my remote! This is going to be a noisy machine. The speed
controllers make a tone noise, combined with the sound of four 24v drill
motors, and eight spinning wheels.
2/28/01
Finished the spindle
assemblies. I think they will work out OK. Picked up some Polished
Aluminum Tread Plate at the hardware store. Looks really cool. I think
I can use the .1" thick stuff for some of my armor. I gave Clobber
Club member James some tapes of most of the BattleBots
episodes. Apparently he's watched them once and is viewing them again.
He's suggesting I use more metal angle because of the inherent strength. I
think I agree, so I'm going to look into how that will effect weight. At
this point, everything is coming down to weight.
2/25/01
Here's a couple more pictures on
what the prototype is looking like. A full
view, and a close up of the spindle
connected to a sprocket driving the wheel. Clobber Club member Mike contributed some ideas for a new personality for
Bundle of Joy. Members Dan and Nick were supposed to meet up with us, but
are MIA. After discussions with Mike, I have developed some new ideas.
Here's a peek at what it's looking like
so far.
Spindles are on order, and I also ordered some sprockets and belts to link
the motors together (not enough room for chain).
Did some weight calculations, based on things I already have, and modeled
CAD elements. It is currently very close in it's current configuration. If
I want to add a wedge or weapon, I will need to loose weight somewhere...
2/20/01
Got the motors into the
prototype. VERY tight fit, took quite a while to get them aligned
properly. Here they are with just the two
structural elements that hold them. Here's what the prototype looks
like together with the motors in it. I believe that with a little half-ass
engineering, I'll be able to use the Dewalt spindles to hold the drive
sprockets. This is good, since my first attempt at grinding my own wasn't
to pretty.
2/19/01
The motors will fit in the frame
better than I thought. I've actually got a little clearance, so holes for
the motor casings will be completely surrounded by metal. Stopping at the
hardware store to pick up a 3/4" Forstner bit and a 2 1/4" hole
saw so I can get the motors into the prototype. Started charging batteries,
don't have the AstroFlight 112D figured out yet. After it got a little
above 5 AH, it went back down to zero, and eventually ended up around 2AH.
Should be 7.2AH ultimately, so I've got to figure out what this thing is
doing...
2/17/01
Finished the batteries.
Developing ideas for an adjustable wedge, details to come. Looking to
spend time tomorrow figuring out the method to mount the motors.
2/15/01
Check out the new BattleBots
website, it's added a lot of new material, including information on how to
build a bot, get a sponsor, or compete.
Also added some new info to the Clobber Club
page. Come join us now!
2/11/01
I've got a crude prototype together, using wood
for the structural elements. So far the wheels, axles and bearings are in.
I'll use this prototype to make sure all my sizing is correct (i.e. everything
fits) before milling the final structural elements. Here's a picture
that includes a universal scaling device.
I also added pictures further describing the work I've done on the wheels,
and the current Team Clobber members.
Got a couple sheets of 1/4" Lexan from
some friends at work. Thanks guys!
03/23/01
It appears that the home page is a better place to
document this stuff. Once Ramming Speed is complete, I'll move the documentation
for it to this page, so the home page can be used for other endeavors...
02/02/01
I've purchased the Dewalt motors, along with the majority of the other parts
I need. I will have 6 wheels on one end, and two on the other. It should drive
like a two wheel robot, using the two on the other end as a form of 'rudder' to
aid in steering. I have a detailed 3D model done in AutoCAD that I will probably
post shortly.
12/26/00
I've done a lot of research so far, and made some decisions. First of all,
what kind of bot to build? From what I've seen on the shows, and read on the
forums, it appears to me that driver skill is critical. Many drivers have very
little time 'behind the wheel', and it shows in the box. Another important piece
is the transmitter/receiver. I've seen numerous bots loose because their drivers
couldn't control them. Finally, durability. If you can last the full 3/5
minutes, your chances of winning are greatly improved. Make sure the bot can
take a licking and keep on ticking.
I'm going to start with a light weight. It will be less expensive (I hope)
for one. I'm also more intrigued by light weights because I consider them more
difficult. It's hard to do everything you want to with the 58 lb weight limit.
I'll try to keep it as small as possible, and very drivable. I'm going to call
this light weight 'Bundle of Joy'. If weight permits, I'd like to have a baby in
a blanket or a basket mounted to the top of the bot with a speaker blaring
crying sounds. It's weapon will be listed as 'compassion'. I'll even add a 'Baby
on Board' doohickey.
As far as weapons go, saws and drills are impressive looking, but
ineffective. For them to work, the opponent has to be still for at least a
couple seconds, which generally ain't gonna happen unless they are dead already.
Hammers and other swinging devices can do some serious damage, but are difficult
to aim, resulting in few hits. Spinners are maybe the most destructive
possibility, but are hard to drive, and can suffer self destruction easily. The
most destructive force that's always going to be in the box is the kill saws, so
I'm going to take advantage of them by building a pushing/ramming bot. The
design will most likely include a wedge for pushing, and a spike for ramming.
I've decided to use drill motors for my drive train. Currently, I'm looking
at the Dewalt 24v hammer drill motors. They produce 550 in. lbs. of torque, and
I intend to use 4. To get the power to the ground, I'll be using 8 wheels from
McMaster-Carr in 4 2-wheel combinations. For power I'll be using 4 Dewalt 18v XR+
battery packs. I'll break them apart and use the 60 cells to give me 24v @7.2
AH. To charge the batteries, I'll use an Astro Flight 112D connected to an Astro
Flight 120 Power Pack.
My concept is to keep the bot as small as possible, but be very drivable.
