The following are the reports each system made for our Preliminary Design Review with Honeywell. These should give some detailed information that accurately describe how each system is going to be implemented. Additions are going to be made periodically to update the progress of our design. The following links will jump to each section.

• IFI ISAAC Control System

The ISAAC system is highly programmable when compared to other arrangements. This will allow us to compensate electronically for mechanical discrepancies, i.e. one drive motor spinning faster than another. The control board inside the robot has sixteen inputs which is plenty of room for all of our robot's components. IFI has gained a reputation as being an extremely reliable brand.

• BPK-3200N-24 BattlePacks

We have chosen to use two Nickel Metal Hydride (NiMh) battery packs. From our research, NiMh is more cost efficient, reliable, and more appropriate for our purposes than Lithium Ion and Nickel Cadmium (NiCad). The specific packs we have chosen are lightweight and compact, yet they provide sufficient voltage and amperage for our system.

• Victor 883 Speed Controller

We will be using two speed controllers - one for each drive motor. The speed controllers we have chosen are lightweight and reliable, with an on board cooling fan, designed for combat robotics. They are compatible with standard R/C equipment because they use Pulse Width Modulation (PWM), an effective method of accurately and precisely controlling moving parts, specifically in this case, drive motors.

• S28-150 Magmotors with TW TWM3M Gearbox

We narrowed down the choices for our drive motors to the S28-400 and the S28-150. We chose the 150's because they are the best motors for our weight class because of their high efficiency and low weight. The values for torque and rpm will satisfy the needs of our robot.


• ANSI roller chain #35

After researching the sizes of the chains, we discovered that the ANSI #50 was far to heavy and that the #25 was to weak for the power that our gearboxes put out. We settled on the #35 chain because it is light and durable enough to meet our needs.

• 1/2" bore 18 teeth, and 3/4" bore 12 teeth for ANSI chain 35

After choosing our chain size, we needed to find which size of sprockets we needed. Our first plan was to go with a 1 to 1 ratio, but with that setting, our robot would be going 18.4 feet per second with the 5 inch wheels. We researched the speed of the Battlebots during competition and found that the average speed is about 10 feet per second. We had to find a speed that we would think is fast enough yet manageable to control and maneuver. We decided that we would want to go with a 12 feet per second speed, and with a few calculations, we came up with a 2 to 3 ratio. In the end we ordered 12 tooth sprockets for the gearboxes and 18 tooth sprockets for the axles of the wheels.

• NPC 5" high traction robot wheel

We considered the 4-inch wheel of the same style, but decided the diameter was to small. Realizing that a wheel too much bigger would take up much needed space, we decided to go up to only the five inch diameter NPC wheel. We are also going to lathe the outside of the wheel in order to flatten the slight arc on the bottom of the wheel and increase our surface area with the ground.

• 5/8" 4130 steel tubing (.035 wall thickness)

As a team we chose to use 5/8" 4130 steel square tubing for our frame. 4130 steel is a well known steel especially in aviation and race cars. This just goes to show how stable and reliable this steel can be. It has great welding ability, and is a strong steel alloy that is light weight. We went with the smaller size tubing due to the weight restriction of 120 lbs.

• 3/8" 4130 steel tubing (.035 wall thickness)

For the same reasons as above, we decided to use 4130 steel square tubing for the frames diagonal cross braces. In order to save weight, we made our bracing steel a little bit smaller. Even though it has less strength, it will still do its job by supporting the frame.

• 7075-T7351 Aluminum

Our Armor/ skin of our bot will be made with this type of aluminum. We went with aluminum because of its lighter weight than steel, but with similar strength. 7075-T7351 Aluminum is used in aviation, and known to be extremely strong when it comes to withstanding immense amounts of pressure.

• Lexan (Polycarbonate)

Our plan is to use Lexan for the skin on the top of our robot. We felt that by using 3/8 inch Lexan would sufficiently cover the top of our robot. Lexan is a great material with its light weight qualities, and still has some durability when it comes compression strength.

• Bimba 3" bore x 4" stroke, double actuating, stainless-steel pneumatic cylinder with air cushions at the end of the stroke. Donated by Flo Products. Custom clevis made from hardened steel.
  
• Crossfire 68 cubic inch fiber wrapped Nitrogen paintball tank - lighter in weight when compared to steel tanks
  
• Nitrogen Regulator - 3000 PSI max input, 175 PSI max output, two gauges - complies with safety requirements
• 24 volt solenoid and 5-port valve for high flow actuation.
• 7075 aluminum for arm and brackets - 7075 is ideal for highly stressed parts. It has a good weight to strength ratio and is one of the strongest alloys of aluminum

Because of the design of the 4 bar linkage, the front link is substantially longer than the back link. With the pneumatic actuator mounted on the longer front bar, it creates requires less torque to actuate the system. The longer link raises the front of the flipper while the shorter, rear link allows the system to move forward at the same time creating a diagonal vector. This will propel the opponent up and away from us, minimizing any damage that might be inflicted on us by the opponent landing on our weapon.

A program called Four Bar was used to graph the torque required to actuate by the height of the arm. The goal is for the initial torque to be as low as possible to ensure the fastest possible actuation.