Small steps. Big impact.


Birth of the Fitbit


Sorry, it’s been a while since our last post. We’ve been tweaking the design to fix some of the issues I mentioned in the last post. I had been hoping to make one single post when all the issues had been resolved, but it’s been taking a while and so instead of keeping you in the dark further, here is the incremental update.

1. We’ve made some changes to improve the assembly time and process. Things can always be better on this front, but I think we’re closed to locked down on this aspect.

2. The button design was changed to make it easier to press. The pressing action is a lot less stiff, due to a softer rubber that we switched to and the shape of the button was altered to make it easier to press.

3. Charging. Ah, this has been the bane of our existence for the past few weeks. I think we’ve made some good progress, though. The stiffness of the contacts has been increased and this has helped in making sure that the contacts would no longer get deformed during the assembly contacts.

However, we still have not been able to get reliable contact between charging contacts. Here’s a couple photos to illustrate things:

Downward Charging Problem Side to Side Charging Problem

You can click through to see the larger pictures, but essentially, there is a lot of side to side movement and up and down movement once the Fitbit has been placed on the charging base station. This movement causes the contacts to potentially miss contact with each other and therefore no charging occurs.

It’s very possible that this misalignment is due to the imprecise nature of the process used to make the prototypes, since we don’t see this misalignment in the computer design files. Our prototypes are made by taking a block of plastic and using a computer driven drill to carve out the prototype. This drilling or “machining” process is a lot less precise than the final production process, which is injection molding: injecting molten plastic into steel molds.

However, just to be safe, we’ve made some more changes to prevent this issue and we are getting some more prototypes built to test things out, but I think it will be at least another 2 weeks before we know the answer for sure. In the meantime, we’ve ordered a lot of the individual electrical components and we expect those to arrive within 8 weeks.

I also wanted to give you a glimpse into the design process that got the Fitbit to this point. In the beginning, we commissioned a top industrial design firm to come up with design for the Fitbit. This firm has done a lot of groundbreaking products including the Palm Zire.

The first stage of the industrial design process was to come up with some basic shape concepts [click through to see larger image]:


Step 1 Shape Concepts

These are a subset of the shapes that we considered. This stage allowed our design firm and our team to come to an agreement about the usability and wearability of the Fitbit.

The second stage was to come up with some more developed pencil sketches of the basic shapes. This would allow us to hone in on the aesthetic direction of the Fitbit. Again, these are just a subset:


Step 2 Sketches


From these sketches, we selected 3 designs that would be further developed into computer renderings. Here’s the rendering of the winning design:


Fitbit Final Step Rendering


You can see the Fitbit’s final U shape evolve from the early shape concepts to the final rendering. You might also notice that the winning rendering is similar, but not quite the same as what our actual final product looks like. There are many reasons for this but the underlying thread is that engineering reality often causes the design to change. For instance, it was very difficult to fit all the components into the shape, so the Fitbit had to be thickened…the translucent display effect shown above was technically challenging to execute in a cost-effective and space-efficient manner, etc. In any case, I think both our industrial design and engineering team did a great job in converging on the actual final design that you see on our front page:

Fitbit with flower screen