With the coming together of better part selection it was possible to look at iterating the initial prototype designs. Using cad files and mockups of the current component list; Screen, MCU, Power etc. The v2 prototpe below was created (Iphone for comparison);

This design was based on a simple 3d printed case. No cover is shown just now so that we can see the layout of the components clearly. While 3d printing is useful, I also had a look around for an off-the-shelf solution. Off-the-shelf can be a cheap and quick way to get a prototype enclosed but generally there can be a lack of space so choosing the right one is vital. I made a layout mock up using the 66 Series Grip Cases from CamdenBoss;

The prototype is coming together. It's also interesting to consider a general "final product" design and what form that will take. A few discussions have resulted in 3 possible directions. All the below are based on a custom pcb instead of off the shelf components;

The design is very similar to standard "sat phones" with a helical antenna ("Rubber duck") on the top. The helical antenna is a point of conflict within the team. From an engineering perspective it gives good signal quality, doesn't take up space internally and isn't generally concerned with its position relative to the sky. However, other points have been made; It's a point of fragility on the device and easily broken, it's considered "ugly" compared to other devices and it adds to the overall size of the device. The other option to a helical antenna is a patch antenna. These require a general position relative to the sky and can't be placed inside the enclosure due to interference from the screen blocking signals. There might be one way around this though;

Placing the patch antenna on a "pull-out" mechanism would allow for the antenna to be hidden away when not in use. This lowers the height of the device but adds a little bit of bulk on the back.

Finally, there's the question of thickness over height. By fitting all of the components behind the screen we can reduce the profile of the device at the cost of adding general thickness. Bringing a total thickness to 30mm - whopping in smartphone standards but still very practical;

The final design will likely changed as we progress further but creating a target goal allows us to keep focused and make design changes while considering the effects on a potential final product. Compromises must always be made at some point.

I'd appreciate any feedback on what people think of the overall designs, do you have one that stands out as a favourite?

JW