A 4-Wheel Car Chassis is a basic mechanical frame designed to build robotic cars and small mobile platforms for educational, DIY, and hobby projects. It usually consists of a flat acrylic or metal base plate with pre-drilled holes for mounting motors, sensors, batteries, and microcontrollers like Arduino or Raspberry Pi. The chassis comes with four DC geared motors, wheels (with rubber tires for better grip), motor mounting brackets, and sometimes a caster wheel for stability. The DC motors are typically low-voltage (3V–12V) and provide good torque for driving the robot. Some kits also include an encoder disc for speed measurement and direction control. How to Interface with Arduino: Motors Connection: Since the Arduino cannot directly drive the motors (because they require higher current), you need a motor driver module like the L298N, L293D, or Motor Driver Shield. Connect the motors to the motor driver outputs (two motors on the left side in parallel and two on the right side in parallel, or control each motor individually). Power Supply: The chassis is powered by a battery pack (commonly 7.4V Li-ion or 9V battery pack), which is connected to the motor driver’s VCC. The Arduino is powered separately through its own supply (or via the motor driver’s 5V regulated output if supported). Control Signals: Connect the motor driver’s input pins (IN1, IN2, IN3, IN4) to Arduino digital pins. These pins determine the rotation direction of each motor (forward or backward). The Enable pins of the motor driver can be connected to Arduino PWM pins for speed control. Programming: In the Arduino code, you can control the motion of the car by sending HIGH/LOW signals to the motor driver input pins. For example, to move forward, set both left and right wheels to rotate forward; to turn left, stop/slow the left wheels and move the right wheels forward.