Initially, Ian and I knew that we wanted to build a spinning Battlebot. We knew that these designs were quite successful in the past and a lot of fun to watch. We wanted to make it round and tapered so it would be ale to resist popular wedge designs and be protected by the weapons on all sides. We also wanted a spinning arm which would hold 5lbs weights attached on either end.
The motor which powers the spinning device is very powerful Brigs and Stratton 12 horsepower 48-volt motor. This motor would propel the spinning arm in excess of 100mph. V belts connect the motor to spinning device allowing proper slippage in order to not destroy ourselves. The wheels will be powered by NPC internal gearbox wheelchair motor and control of these wheels would be done by Victor 883 speed controllers. Neoprene wheels will be putting the power to the ground. Tank style steering (right/left wheels controlled independently) will provide the agility necessary to negotiate the arena. Power is to be supplied by 4 6volt sealed lead acid batteries. The body will be constructed by 1/8" steel and the base ¼".
We were fortunate enough to show our design to two experienced Battlebot builders and five time champions, Alexander Rose and Reason Bradley. They gave us a new perspective on how much force these bots dish out and take during a bout. He said they have to be able to withstand up to 100 Gs of force and be able take consecutive drops of a 10-story building. Thus we concluded a spinning arm would not be durable enough to repeatedly endure such punishment. We later came up with an improved spinning arm but after examination we concluded this type of arm would not be practicable.
The second design we created was a little different. The internal aspects would be the same but the weapon and body would change. There would be a spinning disk out in front powered by the same Brigs and Stratton motor. This will be much more durable but you must point the weapon at the victim as opposed to being protected from all sides.
A lot of time has been spent using AutoCAD,
we have come up with three completely different designs. AutoCAD has
proved to be an invaluable tool for the design of our Battlebot. We
can see how things will fit together and what products will work in
our robot best.Most of the time on this project will be spend in design
phases and much of this is AutoCAD.
In order to tackle this assignment we had a lot of research and learning
to do. We needed to learn how to create a robot from scratch. We learned
about receivers, speed controllers, control system, drive methods,
motors, batteries, electrical properties and many other things.
Construction started with the creation of the internal frame which
is a box 29.5"x29.5"x6" gusseted at all 90º's
made out of ½" box steel. Next we welded four sides out
of 16 gage steel to the box and a bottom out of 10 gage which will
sustain hits form the kill saws. Next came the cross supports that
would hold the bearings that the 1" center shaft would sit in.
In the middle of the cross supports we layed down ½" steel
plate that the bearings would be bolted onto. The top bearing support
had a 1 and ¼" hold drilled in it so the shaft could come
up through. The ½" plating would not be welded into its
box until all ;bearings are torqued down and the shaft sitting in
them to insure absolute parallel so the shaft would spin freely.
Next came the motor mount which would hold the 15 hp Brigs and Stratton
spin motor. Obviously and real sturdy mount would be necessary to
handle the horsepower, weight of the motor in impact and impact transferred
to the motor when the blade strikes. Also the motor would need to
be able to move back and fourth to obtain proper v-belt tension. We
did this by making a plate that is bolted directly to the top of the
motor with grade 8 bolts and was slotted on either side. On the bottom
there were two railings next to each slotted holes. This would enable
us to use 5/16 bolts going through the slotted holes into taped square
pieces of steel that would rest on the railing, this would not allow
the square pieces of steel to spin when tightening the bolts but allow
it to slide. Two plates were then attached to the upper cross supports
that two bolts in each could go down though into the slots. One plate
was welded directly to the frame while the other was bolted in with
12 bolts so the motor would come in and out. Extra supports were made
to the frame in the motor mount places to handle the stress that will
be applied there.
Next came the 1" center shaft. As stated earlier it would be supported by two large bearing that could hold a static force of 2000 lbs each. To keep the shaft from making vertically we will use a brass washer then a 1" rubber piece another washer and a circlip. To make a spot for the circlip we will lathe down an indentation in the shaft. The rubber section would provide some impact resistance. The center shaft will be keyed for the pulley and spin shaft. A set screw will hold the pulley on which will sit above the main body of the bot under a protective cover. The spin motor in pre-keyed and a pulley will sit down on it. To achieve proper gearing a 8.5" pulley will be used on the center shaft while a 2" pulley will be used on the motor.
The spinning blade will be a 1" thick and about 40" wide
with a width of about 4". It will be keyed and have a set screw
to hold it in place. Then the top of the center shaft will be taped
and two 1" bolts will also help hold it in place.
To drive the battlebot we will utilize two 24 volt wheel chair motors,
they will be attached to 4" solid rubber wheels. The positive
and negative leads of the motors will be hooked up to two vantec 883
speed controllers in between the battery. These speed controllers
will be hooked up to our PCM radio receiver. The speed controllers
and the receiver will be shock mounted with rubber between them and
the base of the robot. The front wheels will be fixed forward mounted
on either side with pillow blocks. The battlebot will skid steer meaning
that to turn it will drag the front wheels to turn. On other battlebots
casters have proven to cause more problems then they are worse and
two fixed wheels add stability and help the bot track straight.
The three motors, two 24 volt wheel chair motors and the 15 hp 48
volt Brigs and Stratton lynch motor, will be powered by 4 batteries.
Two 12 volt seal lead batteries will be wired in series to make 24
volts for the wheel chair motors. Two other smaller batteries will
be wired into the 24 volt batteries to create 48 volts for the Brigs
motor. The wheel chair battery will run off two battery and the Brigs
will run off all four. We will adjust battery sizes according so they
will all empty at the same time.
Wedges will be put on all four sides and the corners making a octagonal
shape. They will be hinged and spring loaded to the floor. This will
allow low bots that might be able to fit under the blade to be ramped
up into the blade. Also theses wedges will make it so other battle
bots which are designed to get under us unable to.
Ian and I work very well together which we proved in the previous
year where we made human powered vehicles together. Our strengths
and weaknesses intertwine and create an efficient group. Few compromises
needed to be made because we respect each other's ideas. If there
is a disagreement we will test each idea and see which one is most
practical. Communication is easy with AutoCAD and the use of pictures
and diagrams. Responsibilities and tasks are evenly distributed, we
each handle a part of every responsibility.
Home | Personal Statement | Writing Samples | Work Samples | Skill Evaluations | Resume