Kickstarter

Hi Backers,
We got in the production devices today. We obviously need to have a discussion with the manufacturer. Here are a few pictures of some of the problems we found:

The led is installed at the wrong height. At this height, the led will be recessed in the case.

The correct led height on a prototype:

Some corrosion was visible on the cover on some of the Wi-Fi modules. We're a little worried about this because we have no idea how much corrosion is underneath the covers. Most electronics when being manufactured go through a washing process where the boards are submersed in distilled water to remove dirt and residue accumulated from the manufacturing process. We believe this corrosion is because of insufficient washing and/or drying. About 50 percent of the units we got today have this problem.

Some of the sensor ports were not installed flat on the boards.

One of the Wi-Fi modules got squished by the pick and place machine putting down the module too hard.

The manufacturer forgot to shorten the leads on the button on all devices. This prevents the boards from being installed in the boxes.

An example of the leads cut correctly on a prototype.

So its good progress as we are at least manufacturing production units. I was expecting some issues with the first batch and the issues that we found are not very hard to fix. These units are not of high enough quality to release to backers but with some adjustments and with adequate explanation, I'm confident we can produce high quality Knuts.

Richard

Jay and I stopped by Sunburst EMS in West Bridgewater MA today to drop off a sheet of Knut's and associated parts. Unfortunately, they would not allow us to take any pictures so this is all we have, a picture of all the parts on a carpet.

Sunburst will manufacture 20 Knuts over the next week to give us an idea on any tweaks we need to make before going into full production. We already noticed a small problem that will make it difficult to remove a Knut from the complete sheet of Knut's. We are using small breakaway lines called "mouse bites" which are really just small perforations in the PCB that allow someone to snap a Knut out of the carrier board. Problem is the mouse bites are too strong and could lead to damage parts when someone tries to remove a Knut. So Sunburst has recommended that we score the perforations as well to make an easier breakout. Luckily, this doesn't hold us up in any way as the change is really only needed for future boards.

Yesterday we stopped by Mass Design, a PCB manufacturing facility in Nashua NH. They walked us through the whole process of making a PCB.  Its too much to go into detail here but I thought I would share a few interesting pictures. This is the copper plating tank with a few boards in it. The boards are held by the white plastic rods in a bath of copper sulfate. The purpose of this tank is to create connections from the front to the back side of a PCB. Copper is plated through drilled holes in a PCB creating circuits that can run on the back and front of a PCB.

This is an automated drilling and routing machine. The red light is the light for a camera contained in the same housing and is actually part of a machine vision system with a surprising amount of intelligence. The drilling system will drill holes in a PCB and inspect them to insure they are drilled to the proper diameter. It will also inspect its own drill bits to insure they are not worn out or broken. Its fascinating watching this machine. It can drill around 5 holes per second. The bits get so hot while cutting the PCBs, that a piece of aluminum is put over the PCB to actually cool the drill bit down. Seems a little counter intuitive to be drilling through more stuff to cool something down, but apparently it works.

This is a picture of me and Bill Gately of Mass Design. Bill was the one who was kind enough to give us a full tour of the facility. I'm holding the sheet of wood that was on the back side of the Knut PCB's during the process of cutting the Knut's out of the carrier sheet. Ordinarily this is a disposable but I'm thinking of framing it...

So we've come a long way. FCC and CE are finished and we passed with no modifications of the hardware needed. We only needed a higher quality sticker and a modification to the manual to get through.

We are planning on shipping out these new units to beta testers and if they like them, we will give the thumbs up to Sunburst and Mass Design to do the full order.

In the mean time, I will be cleaning up the remaining software issues.

Shipping is in sight,
Richard

We stopped by the board house today and picked this up:

These are the final Knut PCBs. Tomorrow we are visiting the contract manufacturer to deliver all the parts so they can start assembling the final Knuts. I will let you know in detail on how it went.

Richard

As promised, here are the FCC and CE testing pictures:

Knut in a test chamber about to be hit with 3 volts per centimeter in air. The test chamber is shielded room covered in thousands of ferrite tiles. When the door to the test chamber is closed, almost all radio waves are blocked from reaching the outside world. (Sorry about the bad picture quality):

A prescan being done on Knut to see what radio frequencies is being emitted by Knut when no external interference is applied. The high peak on the left is 2.4 GHz (the frequency of Wi-Fi)

The graphs shown here are the result of a 4 separate scans called presweeps. Presweeps give the testing house an idea of how your device will perform for the rest of the tests. Not unlike pressing the scan button on your car radio, the equipment scans through a very large set of frequencies to see on what frequencies Knut is producing a signal. The straight line in the middle of each graph is the limit and if Knut exceeds a limit, Knut will likely fail subsequent tests. Knut does exceed 1 limit at 2.4GHz but is allowed to because Knut is designed to transmit at 2.4GHz.

This data is not official FCC and CE testing data and I don't have access to the official data until all tests are completely done. This picture is actually full resolution. You need to save this picture to your computer to see it in full detail.

Here is Knut being viewed by a camera inside the test chamber. No one can be in the test chamber during the test because intense radio waves are generated which are bad for human health. A test would take a few minutes and then they would re-enter the chamber and rotate Knut a different angle, and then run another test. Then after a few more tests they would enter the chamber and rotate an enormous antenna.

Knut being shocked with 4000 volts:

This actually went a lot better than I thought it would. Knut messed up a little bit but recovered on its own so it's still considered a pass. Knut had a moment of time traveling when it suddenly reported that it was 2:16:36 PM when it was actually 1:57:43 PM. The battery also indicated that it was empty but then recovered.

Internal Temp 1:56:44 PM 2/1/2013 73.4F
Battery 1:56:59 PM 2/1/2013 99.39%
Internal Temp 2:16:36 PM 2/1/2013 73.4F
Battery 1:57:43 PM 2/1/2013 0.32%
Internal Temp 1:57:44 PM 2/1/2013 73.4F
Battery 1:57:58 PM 2/1/2013 99.39%

Knut had to be field tested to determine how it would act in the real world. It's difficult to test in the real world in the middle of a snow storm. F2 Labs has an awesome inflatable bubble to deal with this. Its kept inflated with 2 huge air pumps and its always under positive pressure. The entrance to the bubble is 2 doors with an air lock in between. If you open both doors, the whole bubble deflates and breaks all sorts of expensive equipment inside. My ears popped a little when I entered, but the people at F2 said that they don't notice that.

A view of inside the bubble. This bubble is huge. You could easily play soccer in here. In fact a some grass is growing on the left. On the left, closest to the camera is Knut on a table.The table can rotate 360 degrees. In the middle, very far away is a gigantic antenna. The antenna can slide up and down. During the test they rotate Knut around and raise the antenna up and down to see what radio waves Knut generates.

Knut in another test chamber:

I had a lot more photos but somehow they disappeared... It's very strange. I took many of various antennas and many additional shots of the first chamber. They might have gone missing during the test that they applied 4000 volts to Knut because that was really the only time that my iPhone was exposed to any strange interference.

Oh and also, Knut passed FCC today. CE has some additional tests that need to be done like drop tests, high and low humidity tests, high and low temperature tests and other tests that take weeks.

Richard

So Knut got a facelift. Sort of. We updated the connector to be sturdier and easier to use, Our beta testing revealed that the old connector did not provide sufficient support for the sensors, nor was it clear which way sensors should be plugged in. In fact the first question we got asked from one of our beta testers was "What direction do I plug in the sensor?".

When we began searching for a replacement, we discovered that finding connectors for electronics is hard, really hard. Considering that we don't have the order quantities needed to get a custom connector (which is usually a 10000 piece minimum) we had to look for off the shelf connectors. We considered many options such as mini USB, mini HDMI, mini displayport (Thunderbolt), Ethernet (RG-45), telephone (RJ-12), and serial ATA, but none of them really fit our needs. A major concern was the connector being able to penetrate the case at the right height (which none of these do). Also we didn't want to have to create custom circuitry to deal with having someone plugging in a let's say a mini HDMI device into the front of Knut and having Knut safely handle the incompatible device.

So we arrived at this:

From left to right: Board to Wire, Board to Board, and Board to Ribbon Cable. And they are all polarized and very durable. Board to wire allows us to make a direct connection to devices on wires such as the waterproof temperature sensor. Board to board allows direct connection to expansions board such as humidity sensor and the accelerometer. Board to ribbon cable allows us to make extension cables easily so sensors can be placed in more remote locations. Based on some pretty extensive research, no other connector seems to be able to do this. But if you know of one, I would love to hear about it.

Also, because we now have 8 pins instead of 5, we are bringing out some additional functionality that will be very useful to people creating their own sensors. If you want to know what we added, shoot us a message.

Knut performs above and beyond our initial expectations and we are confident that this is the production ready Knut. We’re so confident, in fact, that we’ve sent this Knut for FCC and CE testing. I am currently in Cleveland visiting F2 Labs, where testing of Knut will begin tomorrow at 8:00 AM. I will be sure to get some pictures and if I get a chance I will try to get them up tomorrow as well.

It will take 2-3 weeks for Knut to be fully tested for FCC and CE compliance. Once Knut passes, we are going into full production.

Thanks for your patience,
Richard