Do I need to use an arduino for my pi based robot?

Question

I want to start this off by saying that I'm kind of a beginner when it comes to more advanced robots. Before this project, the most advanced project I've made was a simple Arduino obstacle avoidance robot with an HC-SR04, so I apologize if I ask anything stupid. I'm in the process of making a 3d printed Raspberry Pi robot, and have been looking at similar projects. My robot is going to use an RPLidar sensor for navigation. I've noticed that similar projects use an Arduino in addition to the Raspberry Pi. I assume the reason for using the Arduino is to control the motors. I am using two geared DC motors (that look like standard size servos), an L298n motor driver, a Raspberry Pi 3b+, and an RPLidar A1 as the main components (I may add a Raspberry Pi Camera later). Is it necessary to include an Arduino? I also wanted to include a rechargeable li-po battery, and decided to use a 7.4v 850mAh battery to power the motors. I just want to make sure that it is safe to do so.

genebren · Accepted Answer

Sometimes in a complex project, it is easier to run a second processor (Arduino) to host multiple sensors and report results to a host processor (RPi). Also, it is possible that the RPi may not have enough I/O pins to dedicate pins to each of the functions that you need, so an Arduino could provide more I/O ports.

Good luck on your robot project. There should be a lot of good robotics ideas here on the community, be sure to look around and see what others are up to.