The robot chassis design

After computing the robot's motors and wheels parameters, we can design the robot chassis or robot body. As required, the robot chassis should have a provision to hold food, it should be able to withstand up to 5 kg payload, the ground clearance of the robot should be greater than 3 cm, and it should be low in cost. Apart from this, the robot should have a provision to place electronics components, such as a personal computer (PC), sensors, and a battery.

One of the easiest designs to satisfy these requirements is a multi-layered architecture such as Turtlebot 2 (http://www.turtlebot.com/). It has three layers in the chassis. The robot platform called Kobuki (http://kobuki.yujinrobot.com/about2/) is the primary drive mechanism of this platform. The Roomba platform has motors and sensors inbuilt, so there is no need to worry about designing the robot drive system. The following image shows the TurtleBot 2 robot chassis design:

TurtleBot 2 robot (http://robots.ros.org/turtlebot/)

We will design a robot similar to TurtleBot 2 with our own moving platform and components. Our design also has a three-layer architecture. Let's identify all the tools that we need before we start designing.

Before we start designing the robot chassis, we need computer-aided design (CAD) tools. The popular tools available for CAD are:

• SolidWorks (http://www.solidworks.com/default.html)
• AutoCAD (http://www.autodesk.com/products/autocad/overview)
• Maya (http://www.autodesk.com/products/maya/overview)
• Inventor (http://www.autodesk.com/products/inventor/overview)
• SketchUp (http://www.sketchup.com/)
• Blender (http://www.blender.org/download/)
• LibreCAD (http://librecad.org/cms/home.html)

The chassis design can be designed in any software you are comfortable with. Here, we will demonstrate the 2D model in LibreCAD and 3D model in Blender. One of the highlights of these applications is that they are free and available for all OS platforms. We will use a 3D mesh viewing tool called MeshLab to view and check the 3D model design and use Ubuntu as the main operating system. Also, we can see the installation procedures of these applications in Ubuntu 16.04 to start the designing process. We will provide tutorial links to install applications in other platforms too.