03/26/2023

4 By 4 Climbing Robot

Writing about 4 By 4 Climbing Robot for educational and informational purposes only. however, do not hesitate to use this information on your own risk as we make no warranty of any kind.

Design:
3D printed this car/robot using PLA filament on my Ender3 printer. After a couple of tries I realized the best practice is a lighter chassi for best performance. Finding the sweet balance between the weight and the durability was a challenge but I think I got to a good point.
Wanting to keep the body thin and inside the tire so it can drive upside-down and do flips was important and a key feature of the design.
Weight distribution and space optimization is important so having the batteries in the middle is key to having a good balance as I wanted all directions and upside-down performance to be all the same.
Power:
Weight and size again being the focus while keeping good performance the 18650 was my best option.
I tried power banks and other types of batteries and settled on the 18650. It is best to separate the raspberry pi power from everything else so it doesn’t restart due to low voltage when the motors are fully loaded.
I’m using 2 batteries to power the pi and the other 2 to drive the motors.
Wiring:
Using a DuPont cable for most connections except for the main power from the battery to the DC motors driver L293D since I needed to pass a higher current.
Using L293D to drive the motors tank style.
Software:
Using the raspberry pi zero W on this 4 by 4 and python code to drive it from my phone using the bluedot API and phone app.
Component list of the parts used:

• Raspberry Pi Zero W – this is the brain on the robot
• Power Supply
• L293D DC motor driver
• 4 x 18650 rechargeable batteries
• 4 DC motors and tires
• DuPont cables
• 3D Printed chassi