The purpose of the combat robot program is to increase community awareness and interest in the Carlmont Robotics Program and STEM classes while raising funds for the program and ensuring the participants have fun.
Two robots compete in a head-to-head match following the basics of boxing. Robots are teleoperated. Like boxing, the robots are given a set amount of time to fight, in which either one of the robots is knocked out or the match time runs out, and a judge decide the winner.
The arena shall always be set up to have a Lexan shroud around the main field of combat. This is needed to protect the participant and observers should any parts or debris come loose. In addition, this added protection serves as a barrier to keep unauthorized people from reaching into the arena.
Construction of Robots
Robots should weigh less than or equal to 300 grams Weapons can consist of pushing, clamping or flipping mechanism. Weapons built can’t cause harm to the audience or drivers. Robots should be reliable and easy to fix if needed Receivers and batteries need to be easily accessible so that they can be quickly changed out Main materials available for each robot: 2 - 30:1 micro geared motors 1 - HTK 12 servo 1 - 12” x 12” x ⅛” sheet of UHMW 1 - 12” x 12” x .118” sheet of polycarbonate 2 - VEX #29 motor controllers 1 - radio receiver Turnigy nano-tech 180mah 2S 25~40C Lipo Pack 1/16” aluminum
Stage 1: Choosing a design Given that we aren't using any extreme weapons like blades, flamethrowers, or full body spinners, the number of design types are somewhat limited. Additionally, keep in mind that this is a fundraising initiative, so a robot that requires new parts or is destructive would not be very practical. This would typically limit the designs to wedge robots, clamping robots, or lifting robots. However, other creative designs are still feasible and unconventional designs can often bring in crowds.
Stage 2: Developing the Design There are two typical pathways for designs a minibot. Either way, it is important to make sure that the robot has enough space to fit the internal components
The first way is making a CAD model of the robot. This allows members to gain more experience with Solidworks and specific procedures like using the Vault and creating dimension drawings.
The second method is drafting out a detailed picture of the robot. This method is typically quicker, but has more issues down the road as it doesn't have the complete visualization that CAD provides.
Stage 3: Building This stage is basically what it says it is. It consists of fabricating parts and wiring together the electrical components
Here is the link to how to solder the components:
Stage 4: Assembly For assembly, the easiest way to put the components together is with 1/4" by 1/4" UHMW strips and wood screws in each of the robots inside corners. Additionally, it is important to include a plan for the mounting of motors and servos. It is also important to understand how to plug in the wires into the receiver
Stage 5: Testing For this phase, make sure that you know how to set up the robot. Just plug in the servo plugs into the correct slots in the receiver and plug in the battery
Basic Tutorial for the construction of Minibots: http://www.fingertechrobotics.com/images/servo201304_give_yourself_a_weapon.pdf
LiPo Battery Charging Notes:
LiPo batteries are generally safer and more environmentally friendly than other R/C batteries like NiCd and NiMH. LiPo batteries have become the most common high performance R/C battery. However, if charged, discharged, stored, maintained, or handled improperly, they can become extremely dangerous. When maintained carefully LiPo batteries are very reliable and will last a very long time. As such the following instructions should be followed very closely LiPo batteries are lightweight and very effective but have the same problems as other lithium-ion cells. This means that overcharge, over-discharge, over-temperature, short circuit, crush and nail penetration may all result in a catastrophic failure, including the pouch rupturing, the electrolyte leaking, and fire. If you notice that the battery is damaged or puffed up (expanded), do not use or charge. Bring the battery to Leadership, Mentor, or Teacher to review and determine what to do with the battery.
LiPo Fire: A LiPo fire is a chemical fire. Always keep a Class D fire extinguisher nearby your battery charging/discharging and storage area. The battery charging/discharging and storage area should be free from any materials which can catch fire such as wood tables, carpet, or gasoline containers. The ideal surface for charging and storing LiPo batteries is concrete or ceramic.
Charging: NEVER LEAVE BATTERIES UNSUPERVISED WHEN CHARGING Charge the battery after every use as this will extend the life cycle of the battery. Additionally, if the battery voltage gets too low it will not be able to be recharged. The battery charging/discharging and storage area should be free from any materials which can catch fire such as wood tables, carpet, or gasoline containers. The ideal surface for charging and storing LiPo batteries is concrete or ceramic. Hook up the battery to the charger and plug in the balance plug Make sure charger settings are set correctly Battery Type: LiPo Charge Type: Balance Cells: 2*
- Initial batteries that have been purchased for the Combat Robotics outreach program. May change in the future
NOTE: If you get a Low Voltage Error bring the battery to Leadership, Mentor, or Teacher to review and use the special instructions below:
Storage: LiPo batteries should always be stored and transported in a metal ammo box to protect against damage and for fire suppression. Do not allow batteries to be stored in direct sunlight for an extended period of time. Always store your LiPo batteries at room temperature. Do not store them in a hot garage, or in a cold refrigerator. Even though a cold battery has less chemical reaction taking place which can prolong its lifespan, taking a battery out from a cold fridge can cause condensation to occur on the inside of the battery, which can be very dangerous. Never leave your LiPo batteries sitting around on a full charge for more than 2-3 days. If by the 3rd day you realize you are not going to use your battery today, you need to discharge your battery down to 3.6v-3.8v per cell for safe storage until you are ready to use the battery again. Special Instructions for recovering a LiPo battery that has been NOTE: These instructions need to be followed exactly as the potential for damage, fire or battery explosion are higher if not followed exactly. DO NOT LEAVE THE BATTERY OR CHARGER UNATTENDED when following the Special Instructions ONLY AUTHORIZED AND TRAINED LEADERSHIP, MENTORS OR TEACHER should perform the activities below: Hook up battery to the charger but do not plug in the balance plug Place the battery in the charging bag and close the Velcro top Set the charger to the following: Battery Type: NiMh Charge Type: Charge Voltage: 0.01 or lowest setting Under constant supervision start the charge process and stop the charge process when the total voltage reaches 3Volts times the # of cells. For 2 Cell LiPo batteries this will equal 6 Volts (3 Volts times 2 cells = 6 Volts) Stop the charge process and follow normal instructions above. Ensure the settings are set back to LiPo.