I test fitted the strand of LEDs to see how well they were being diffused. You can get more illumination when they're pointing towards features. The further away the light source, the more soft and diffused the surface appears.
Install LED Strand
With the LED strand now tested and adjusted, it's time to mount it to the inside of the robo body. I used mounting tack to secure each LED to the surface of the body. A moderate glob of tack is suffice to mount an LED in place. It was a bit tricky to fully fit my fingers in the body, so you'll need some finesse. Maybe a pair of tweezers can help with this.
Adjust LED Strand Wiring
It's difficult to fully see inside the robo body, but you should be able to see where the LEDs are mounted and how the wires are lined up. Take the opportunity to adjust them so they're right up against the surface wall and evenly distributed. You'll want the two wires to stick out from the top of the body.
Connect LED Strand
Now it's time to connect the LED strand to the perma-proto PCB. Solder the voltage wire from the LED strand to the an available voltage pin on the perma-proto PCB. Then, solder the ground wire to a ground pin.
Attach Head To Body
To attach the head to the body, we'll need to install the Trinket, Perma-Proto PCB and wiring through the top part of the robo body. Slowly and carefully fit all of the components through the body – The micro servo at a slight angle. The bottom of the head features tabs that lock to the body. Twist to mate the tab features and press in to fit the head to the body.
JST Slide Switch Adapter
Although we could just connect a lipo battery directly to the Trinket, it would just stay powered on until the battery ran dry. I found it necessary to use a JST slide switch adapter to easily connect/disconnect a lipo battery. This is kinda of a project on it's own. Luckily, I've already created a learning guide on how to fashion one together.
The bottom cover part has a dedicated spot for housing a slide switch. It is installed at an angle and firmly pressed in place. The switch actuator is accessible from the other side.
Connect the battery to the switch by plugging in JST connectors. The battery can be installed onto the bottom part with mounting tack or double sided tape. I wrapped the cable from the battery around the servo mounting platform. I was able to sandwich the battery in between the platform and switch holder. I also trimmed the cable from the battery short – only do this if you know what your doing.
Connect Switch to Trinket
The JST switch adapter can now be plugged into the Adafruit Trinket. If the circuit powered on, slide the switch to power it off – We need the circuit to be stationary while we install the bottom part to the body.
With the battery and switch now connected to the Adafruit Trinket, we can finish this project by closing it up. I carefully embedded the components into the body and adjusted the wiring. Slowly fit the bottom part over the opening and orient it so the cabling from the micro servo is lined up with the notch in the mounting platform. Check to ensure none of the wires are being kinked. Carefully press the bottom part into the body so the micro servo is fitted into the mounting platform. The bottom part has nubs on the sides that lock into the body. Twist until the parts lock together.
Head Rotation Tests
Good idea to test and see if the head can rotate freely before we flip the switch. Slowly rotate the head back and forth. The head should be able to rotate ~180 degrees. If you find the head gets stuck, a wire might be snagged or maybe the there's some access debris in between the head and body. A filing tool should be able to smooth that out.