The First thing I did was go on amazon.com and bought the Raspberry Pi 3 (B/B+) and found a small portable projector that had a built in battery already. I wanted to create a gaming system that can be used anywhere for someone who doesn't like taking bigger consoles to friends houses.
Step 1: Program the Raspberry Pi
The first thing I had to do was download the OS Retropi on the SD card for the Raspberry Pi. I followed along step by step from a youtube video to help along this process. I then had to configure my usb controller.
Step 2: Take the Projector Apart and 3D Print a Mounting Case
The next thing I did was take the top cover off the mini projector in order to screw together the raspberry pi onto the projector. I got my mounting case for the raspberry pi off of thingiverse.
Step 3: Finding a Powersupply for the Raspberry Pi
The portable projector already has a built in battery. However, the raspberry pi needed a power supply, so I tested using a powerbank. It was enough to power the raspberry pi and I used velcro to attach it to the side of the mini projector.
Step 4: 3D Print a Compact Stand for the System
I needed a stand to adjust the projector if needed and not to keep it flat on the ground. I got my design off of thingiverse.
Step 5: Final Product
To keep the HDMI cord and the power cord more compact I zip tied them together. I also looked for the smallest power cord and HDMI cable I could find.