Hey y’all. Joey here. It’s been about a month since I told you Sensor Watch would be shipping in about a month, and hey, good news everyone! Sensor Watch Pro orders for backers are set to ship to Mouser next week. With 1-2 weeks for processing at Mouser’s warehouse, they should be going out to you in early to mid-June, which means now is the time to double check that shipping info!

Aside from manufacturing moves, this past month has brought a ton of improvements to the new firmware, Second Movement, that I’ll get into in a moment. But first, I want to give the full info dump on logistics.

Logistics Update, and the Backer Box

Last month I mentioned that I’d hired my buddy Ben to help with the testing, packing and shipping of your orders. At this point, Ben has tested all of the accelerometer boards, and bagged up all of the custom LCDs.

He’s also folded up 700 of these:

We always knew that we’d need some way to kit up the three parts — the main board, the accelerometer and the custom LCD — that are going out to backers. One option was to ship everything solo, like we did with the 2022 Sensor Watch. Still, I liked the idea of doing something more fun here. To that end, I designed this custom box, with a starry vaporwave aesthetic inspired by the traces on an early purple Sensor Watch prototype from OSH Park. The box is very nice, printed on glossy white paper that really makes the colors pop, and I hope it’ll remain a useful box for all your Sensor Watch paraphernalia after it serves its main purpose.

Anyway: all of these boxes are currently packed with one accelerometer sensor and one custom LCD. The missing piece is the Sensor Watch Pro main board, and the good folks at Cyber City Circuits have been hard at work on that front. So far, they’ve finished manufacturing, testing and flashing firmware to 700 boards: enough to fulfill all backers. Even as I write this, they’re being individually bagged and packed up for shipment.

These 700 boards will be headed my way tomorrow. As soon as I get them, we’ll finish packing them into those boxes so we can ship them to Mouser. At that point, phase 1 of the shippening will be complete. From there, CCC will finish up 400 more boards in early June to fulfill all post-campaign pre-orders, then delivering one last batch in late June to give Crowd Supply more stock for the rest of the year.

Movement Improvements

This last month has also seen massive improvements to Second Movement, the new community firmware for Sensor Watch. Perhaps the biggest change, the one likely to spark the most joy, is Second Movement now stores your configuration on the little file system on Sensor Watch! This means after you change the battery — or simply crack open the watch to swap out the firmware — your preferences, time zone and location will be right where you left them.

Another big change involves the work we’ve been doing adding custom LCD support throughout Second Movement. The firmware that ships with Sensor Watch Pro supports both LCD’s right out of the box; all you have to do is press the bottom left button at boot to select the Classic LCD, or the bottom right button to select the custom LCD. You saw a preview of the LCD improvements in a previous backer update, but now it’s much more integrated. Take this example:

In the image above, the Sunrise/Sunset watch face shows “SET” on the new LCD instead of “SE” for sunset, which is helpful. But it also helps disambiguate a sunSET from, say, a world clock for SEAttle:

More generally, these extra letters and general improvements help all over the place. In the Temperature watch face, the new LCD offers an additional digit of precision after the decimal point, and a new API for stretching a word across the whole top row allows for the more descriptive “TEMP” instead of “TE”:

The Countdown Timer watch face also benefits from this longer title — but it also leverages a new feature of Second Movement: tap detection. If you bought the accelerometer sensor board, the countdown timer in Second Movement will automatically detect its presence and enable tap detection, so you can quickly set the timer’s duration by tapping once on the watch for each minute you want to add.

At this time, the countdown watch face is the only one making use of this new functionality, but I’m very stoked to see what folks make with this new feature. Like everything in Movement, it’s exposed via an API that aims to be as simple as possible: just call movement_enable_tap_detection_if_available to enable tap detection, and movement_disable_tap_detection_if_available when you’re done.

Activity Updates

One important point: while the default firmware on Sensor Watch Pro will support the accelerometer in the form of tap detection, it’s not going to come with activity tracking. To get that, you’ll have to download a firmware image with the new “Activity Logging” watch face. The reasons for this are twofold: first, I’m not certain that everyone who bought Sensor Watch Pro plans to use the accelerometer board, and second, activity tracking is still something that’s actively being worked on.

The Activity Logging watch face currently logs “active minutes,” which requires a bit of explanation. I’ve configured the accelerometer to sample acceleration 1.6 times per second. If, when it takes that sample, it’s experiencing an acceleration change of more than 1g on any axis, it asserts a signal that indicates the wearer is in motion. That signal stays set for about 10 seconds, and if in that interval it experiences another change greater than 1g, it resets the 10 second timer.

The activity logging watch face samples this signal at the top of every minute, and if the wearer is in motion for two minutes in a row, it counts that as an “active minute.“

This method seems to work well at detecting workouts. Or rather, I should say: it seems to work well at detecting workouts for me, but I haven’t had a chance to test it on people of different genders, ages, body types and lifestyles. There’s a lot of fine tuning to do here! For example: is 1g the correct threshold value? Right now my workouts consist mostly of running. Would a configurable threshold allow people to capture a brisk walk? Do we need to count two consecutive minutes of motion, or maybe extend that to two out of the last three minutes? And what of sleep tracking? I’ve got some ideas there, but the code needs work to get its power consumption down.

Anyway: I’m eager to get feedback from folks once they have this gadget on their wrists, as more feedback will give me more confidence in the feature. I’m also more generally stoked for folks to start experimenting with the accelerometer in different directions! In the meantime though, I’m continuing to work on the feature, and hope to have more to share soon.

Sensor Watch Pro at Crowd Supply’s Teardown!

Finally, just a quick note that I’ll be at Crowd Supply’s Teardown conference in just a few weeks! I’m giving a talk, “From Milliamperes to Microamperes: Lessons in Low-Power Gadgetmaking”, that’s heavily inspired by my work on Sensor Watch, and more generally I’ll have Oddly Specific stickers and swag to give away. Reach out if you plan to attend! Perhaps we can get hacking on some cool Sensor Watch Pro features while we’re there.