Button board assembly was pretty straightforward.

We placed all four push buttons in their positions, flipped the board over, and then used a soldering iron to solder all the leads of the push buttons.

• For the assembly process of this PCB, we use a solder paste dispensing syringe. We apply solder paste to each component pad to begin the Main Circuit Assembly process. Here, we are utilizing Sn/Pb 63/37 solder paste, which has a melting temperature of 190 °C.
• Next, we pick each SMD component and place it in its correct location.
• All of the components are then permanently bound to their pads when the entire circuit is set on the reflow hotplate, which heats the PCB to the solder paste melting temperature.
• Next, we positioned every THT component, including the Type C port and the vertical push button, in their proper location. We place the Type C Port on the top side, but flip the position of the push button and place it on the bottom side. Using a soldering iron, both components are soldered in their position.

For the power source of this project, we are using a lithium-ion cell, the 14500 form factor 3.7V 600mAh Li-ion cell, to be precise, which comes with a pre-installed PCM circuit. This PCM circuit protects the cell from overcharge and over-discharge, and it even provides short-circuit protection.

• The cell’s B+ and B- are soldered to our power management board’s battery terminals using a soldering iron.
• To test the setup, I used a multimeter, pressed the vertical button which turns ON the circuit, and we can see the indicator LED light up.
• Using the multimeter, we can check the output voltage of the circuit, which measured a stable 5V, meaning the setup is working.

The electronic setup of this project consists of the UNIHIKER M10 paired with the button board in the following order:

• Button A is connected to P3 of the UNIHIKER.Button B is connected to P0 of the UNIHIKER.Button C is connected to P1.Button D is connected to P2.
• We have also used the onboard buzzer, which is paired with P26.
• Next, we paired the power board’s 5V and GND terminals with the 5V and GND of the UNIHIKER using a pair of connecting wires.
• By pressing the vertical push button, the setup turns ON, and the UNIHIKER screen lights up, signaling that the setup is working.

• We now begin the assembly process, which starts with placing the button board over the four screw bosses. Then, we secure it using four M2 screws.
• Next, the lithium cell is placed in the lower body, where we have modeled a battery holder. The circuit is also placed in its position over two screw bosses and tightened in place using two M2 screws. We use a little hot glue to keep the cell intact and in place.
• We use superglue to attach the aesthetic part we modeled and place it over the front body. We apply superglue to the front side, place the aesthetic part, and secure it in position.
• The UNIHIKER M10 is positioned from the inside of the front body. We use hot glue to keep it securely in place.
• The 3D-printed buttons are added in their place from the inside of the front body. Then, both the front and back bodies are put together and secured using four M2 screws.
• Next, the knob part is added in place on the front side of the device. This knob serves only an aesthetic purpose and is not functional.
• From the front side, we place the shade part in position and mount it using two M2 screws.

To make the device wearable, I attached an ID card strap so it can be carried more easily.

The strap hook is clipped onto a custom part I designed on the left side of the enclosure. Once attached, the device can be worn just like an ID card.

Here’s the end result of this project: PathFinder, my DIY digital map device that helps fellow travelers find their path. It’s basically a map inside a screen, loaded without Wi-Fi or any internet connection. Using the directional pad, we can easily navigate the map.

The map is designed to look like the one from Fallout: New Vegas, with the amber tint, but it shows my town, which is pretty cool.

To test the device in real life, I took my motorcycle out and went to an area I hadn’t been to before. I tried navigating using the PathFinder, and it worked quite well.

I followed the map, went onto a road in the middle of nowhere, actually in the middle of a jungle, navigated through it, and eventually got back to a familiar highway.

This map works, and it works quite well, but I ran into a few issues during field testing.

The most annoying one was the display. The backlight of the UNIHIKER display is quite dim, making it difficult to read under direct sunlight. I even designed a shade for it, but that didn’t help much. On top of that, the display has a shiny, reflective layer for the touchscreen, which makes visibility even worse outdoors.

Another limitation is the map size. Right now, the map covers a limited area of around 2000×2000 pixels. This can be increased by modifying the size in map.py, but doing so makes the code heavier. So, I need to figure out a way to scale the map efficiently without significantly increasing the code size.

I also realized that this device might be more practical if mounted on my motorcycle instead of being worn like a badge.

In that setup, I could expand its functionality by adding temperature sensors, video recording, or even some AI features like tracking vehicles ahead. It could even include a Bluetooth speaker if mounted on the bike; possibilities are unlimited.

For version 2 of this project, I’ll be working on fixing basic issues first and maybe even taking it along on a ride somewhere.

Special thanks if you made it this far, and I will be back with a new project real soon!

Peace.