CamJam Edukit 3 Inspired Robot

CamJam Edukit 3 Kit

The nucleus of my robotics project is the CamJam Edukit 3. For those who are not familiar with the kit, essentially it is a bunch of preselected components that allow you to create a two-wheeler robot using a Raspberry Pi as the brains of the operation. The robot chassis is commonly constructed using the kit box. The kit is created by the team at the 'Cambridge Raspberry Jam' which is a meet up of instructors and children to learn how to code and create with the Raspberry Pi. Click the link on the picture to jump to their website.

So… Back to the robot!

The write-up below has rendered images of my Raspberry Pi robot. My images were captured directly from the 3D model in Fusion 360, and the model can be viewed 'live' online by clicking the link button below. (Viewing the model will only work on a desktop or laptop computer, unless you select the 'desktop view' setting on your mobile phone or tablet browser.)

Here's an interactive online 3d model of the robot.

For my robot I have decided to add more components that are not provided with the CamJam Edukit. I have also designed a custom 3D printed chassis to attach the components too. My design that I created, was built up using Autodesk Fusion 360 design software. The software allows you to join components together and make adjustments to them, as well as create new components on the fly in their original place. I have set up a repository for this project on Github, here is the link – https://github.com/NoobCoder-and-Maker/CamJam-Edukit-3-Inspired-Robot.

Two separate battery supplies will power my robot. One will be 4AA batteries for direct motor and servo control, and separately, two 18650 LiPo batteries will supply power to the Raspberry Pi along with a small 'buck converter' to regulate the voltage to 5v. The robot will feature 3 IR light sensors on the underside for following a line on the ground as well as a HC - SR04 ultrasonic beam sensor at the front for sensing distance or this may-be substituted for a RCWL 0516 Microwave Radar Sensor.

The robot chassis is constructed with 4 quarters(see below) which feature lap joints on each. These are to be fastened together with M3 x 8mm Pan Head Bolts.

Front Left Robot Base

Front Right Robot Base

Rear Left Robot Base

Rear Right Robot Base

The underside view on to the right, shows the small array of IR photo sensors for line following abilities as well as the ball castor at the front. The ultrasound sensor bracket is held in place by fastening on the ball castor housing. There is also a battery box for the 4xAA batteries which sits in a small rack. The battery box slides into the chassis through an opening in the rear panel.

The driving motors are commonly called DC Gearbox Motors - "TT Motors" and they work within the range of 3 to 6V DC. I have attached TT Motor Encoder disc's and Photoelectric IR Through Beam Sensors to both motors so the speed and rotational direction of each motor can be controlled and recorded more accurately. The IR sensor takes readings every fraction of a second from the light that is shone through the rotating encoder discs aperature's which is then used to calculate the speed and rotational distance covered. On the right is a computer rendering of the motor assembly and how both the encoder disc and the photo sensor are attached to the underside of the robot chassis. The TT motors are fastened to the chassis with 4 small self tapping screws which are fastened and accessed before the wheels are pushed onto the drive shafts.

At the front of the robot is a pan and tilt camera mount for the Raspberry Pi camera module. This is moved by using two micro 9g servos. These servos will eventually be controlled either by a hand-held control pad, or through http instructions on a custom-built webpage. The pan & tilt module is fastened to the topside of the robot chassis.