After re-purposing some of the extrusion I ordered for this project to build a frame for my son's room I was back to the drawing board on this one.
I was planning on ordering some more, but then stumbled on a company called Totem, who specialise in mechanical and electrical prototyping kits.
After speaking to the guys there about the prospect of using their maker kits to construct a frame for this project, they have kindly agreed to send me a kit to use on this project in exchange for me documenting my use with it.
This is awesome!
This is a link to the kit I will be using:
The kit looks great; the lengths and panels can be cut to custom sizes and shapes, and has plenty of fixings to create all kinds of shapes and mountings.
The plan will be to create a rectangle for the slide frame (which will hold the ping sensor at the top), then a rectangle back section with mounting spots for the arduino, Pi and batteries, and a square section on the end of it to hold the car speaker.
I really can't wait to get the kit and see what I can come up with!