How to Make a LEGO Robot for a Joust Event

Draft the design of your LEGO robot based on the objectives you want it to achieve, using a pencil and paper to record your ideas and a rough sketch of the design. The design used will be largely influenced by the style and rules of the LEGO joust competition in which the robot will compete. There are also a number of strategies that can be employed in bot design, such as creating a heavy robot with a strong body for defense, or creating a small and agile robot that is capable of evading charges and attacks. Robots for jousting events can take a number of forms, but typical battle robots are driven by wheels or treads and have a low center of balance to avoid flipping.

Build the basic chassis of the LEGO robot using LEGO Technic beams and other large LEGO pieces. Leave room for the crucial components that you will be adding later, such as the programmable brick and the drive system. Build the chassis to be low to the ground and compact; this will make the bot more sturdy and resistant to flipping or damage. Minimize structural weaknesses by avoiding an elongated body shape and using the bot's frame to shield the critical components.

Add LEGO components to your robot that will allow it to perform in the battle event according to your design. If your robot is wheel-driven, you will need to add a steering mechanism to the front wheels -- rack-and-pinion steering designs are popular among Mindstorms enthusiasts due to their simplicity and easy LEGO replicability. LEGO gearboxes allow for gear reduction properties to be used, allowing designers to fine-tune the action of any LEGO motors. Mindstorms pieces such as servos, motors, pistons and sensors should be mounted to the chassis in a low-profile location where they will not be highly exposed to damage during the joust.

Plug the LEGO Mindstorms programmable CPU brick into a computer adapter which is connected to a personal computer with programming capabilities. Most LEGO Mindstorms sets include consumer software that can program in RCX Code. There are also a number of third-party software applications that allow programmers to code Mindstorms in different programming languages such as C++, Ada, Python or Perl. Once the CPU brick is linked, use your Mindstorms software of choice to create the functional program that your robot will use. If the joust event rules allow remote bot control, the program will need to include code that links the remote control device to specific functions on the bot -- for example, the forward and reverse buttons can control the action of a single motor while the left and right buttons control the action of a separate motor for steering. If the joust event is automated-only, a bit more programming skill will be required to turn the bot into a battle-worthy creation. When you are finished, eject the device from the computer and unplug the brick.

Insert the CPU brick into your robotic creation and connect the program-driven components to their corresponding jacks on the brick. Place the creation in a test area and give it a test run to be sure that the major components work as planned. Fine-tuning of the programming can be done later; at this stage, it is important to make sure that the physical design of the bot does not hinder its movement. Make any necessary adjustments.

Add LEGO plating, or armor made of other materials if the event rules allow (and your bot is capable of carrying the load). Be sure to shield the critical components, especially the wheels/treads and any weapons systems, as the robot will be useless in a joust if these pieces are broken or disabled. Test your bot as you go, modifying the program or the physical design as desired until you are satisfied with the end result.