# Mechanical Design and Assembly

## Chassis and Assembly
We built the robot using the tools we had. The chassis and almost all of our custom parts are 3D printed using PLA. To put it together, we used tools like a soldering iron, different sizes of screws, nuts, washers, screwdrivers, and pliers. We also used tweezers for tiny parts and double-sided tape to attach some components. 
We wanted the robot to be small but still big enough to hold all the parts. So, we made a 2-level robot. We put the battery and DC motors in special slots under the first level. We tried a few designs before finishing the robot. In one design, the battery and motor were on the first level, but this made the robot too tall. Being too tall caused balance problems during turns and made it hard to place the sensors at the right height from the ground. 

## Drivetrain and Differential
We used a differential to share the motor's power smoothly between the wheels. When the robot turns, the wheels cover different distances, so we needed a system that lets them spin at different speeds. We used equal-sized gears inside the differential to prevent torque differences between the wheels. For more details about the torque difference caused by the motor and the outer gear, please check the torque calculation file in the calculations section. 

## Steering Geometry
We used only one servo motor for the steering to make the system more efficient. Our steering system has three main parts: parts attached to the wheels, side parts connected to them, and a middle part connected to the servo. The parts on the wheels control the direction, and the bearings inside them help the wheels spin smoothly. 
Using these parts (which form the kingpins) and the straight distance between the rear differential and the kingpins, we calculated the Ackermann steering geometry. This Ackermann setup helps the front wheels turn easily at different angles. You can find these details in the "Ackermann calculation" file in the calculations section.