Ride On With FOSS And GoldenCheetah

December 3, 2025 by Bryan Cockfield 4 Comments

If you exclude certain companies like Peloton, the world of cycling technology is surprisingly open. It’s not perfect by any means, but there are enough open or open-ish standards for many different pieces of technology from different brands to interoperate with each other, from sensors and bike computers and even indoor trainers to some extent. This has also made it possible for open source software to exist in this realm as well, and the GoldenCheetah project has jumped in for all of us who value FOSS and also like to ride various bicycles from time to time.

GoldenCheetah focuses on gathering data from power meters, allowing cyclists to record their rides and save them in order to keep track of their training performance over time. It works well with sensors that use the ANT+ protocol, and once it has that data it can provide advanced analytics such as power curves, critical power modeling, and detailed charts for power, heart rate, and cadence. It can display and record live indoor-training data, and in some situations it can even run interval workouts, although not every indoor trainer is supported. There are no social features, subscriptions, or cloud requirements which can be refreshing in the modern world, but is a bit of a downside if you’re used to riding with your friends in something like Zwift.

All in all, though, it’s an impressive bit of software that encourages at least one realm of consumer electronics to stay more open, especially if those using bike sensors, computers, and trainers pick ones that are more open and avoid those that are proprietary, even if they don’t plan to use GoldenCheetah exclusively. And if you were wondering about the ANT+ protocol mentioned earlier, it’s actually used for many more things that just intra-bike wireless communications.

A side view of an Asian woman with brown hair. She has a faint smile and is wearing an earring that looks somewhat like a large copper snowflake. Near the ear hole is a small PCB with a blinking LED. To the right of the image is the text "LED Earring, Recieved power 50 µW"

Power-Over-Skin Makes Powering Wearables Easier

November 4, 2024 by Navarre Bartz 33 Comments

The ever-shrinking size of electronics and sensors has allowed wearables to help us quantify more and more about ourselves in smaller and smaller packages, but one major constraint is the size of the battery you can fit inside. What if you could remotely power a wearable device instead?

Researchers at Carnegie Mellon University were able to develop a power transmitter that lets power flow over human skin to remote devices over distances as far a head-to-toe. The human body can efficiently transmit 40 MHz RF energy along the skin and keeps this energy confined around the body and through clothing, as the effect is capacitive.

The researchers were able to develop several proof-of-concept devices including “a Bluetooth
ring with a joystick, a stick-and-forget medical patch which logs data, and a sun-exposure patch with a screen — demonstrating user input, displays, sensing, and wireless communication.” As the researchers state in the paper, this could open up some really interesting new wearable applications that weren’t possible previously because of power constraints.

If you’re ready to dive into the world of wearables, how about this hackable smart ring or a wearable that rides rails?

Continue reading “Power-Over-Skin Makes Powering Wearables Easier” →

An image of the track system of the Calico wearable on top of a garment. Different possible positions of the device (elbow, shoulder, etc) are shown by red dots overlayed on the top of the image.

The Calico Wearable Rides The Rails

September 14, 2022 by Navarre Bartz 12 Comments

If you’re feeling underwhelmed by yet another smartwatch announcement, then researchers at the University of Maryland may have just the wearable for you. Instead of just tracking your movement from one spot, Calico winds around you like a cartoon sidekick.

Using a “railway system,”(PDF) the Calico can travel around a garment to get better telemetry than if it were shackled to a wrist. By moving around the body, the robot can track exercise, teach dance moves, or take up-close heart measurements. Tracks can be magnetically linked across garments, and Calico can use different movement patterns to communicate information to the user.

This two-wheeled robot that rides the rails is built around a custom PCB with a MDBT42Q microcontroller for a brain which lets it communicate with a smartphone over Bluetooth Low Energy. Location is monitored by small magnets embedded in the silicone and plastic living hinge track, and it can use location as a way to provide “ambient visual feedback.”

The researchers even designed a friendly cover for the robot with googly eyes so that the device feels more personable. We think animated wearables could really take off since everyone loves cute animal companions, assuming they don’t fall into the uncanny valley.

If you love unusual wearables as much as we do, be sure to check out Wearable Sensors on Your Skin and the Wearable Cone of Silence.

Continue reading “The Calico Wearable Rides The Rails” →

Workout Timer Has Its Own Fight Bell

March 8, 2012 by Mike Szczys 4 Comments

This workout timer turned out great. We think [Douglas] managed to end up with a professional look and a full range of features even though he was doing a lot of learning along the way.

He wanted a clock that was capable of counting up or down to time different segments of his workout. In order to be really useful it needed to have a remote control and a way to signal when time had run out. He grabbed an Arduino and started prototyping with an LED marquee at first, but after adding a second Arduino to deal with the display scanning issues he finally switched over to these LED segment displays.

The timer includes an IR receiver so that it can be controlled with a handheld remote. The large red bell to the side has a heck of a ding and is used to signal the start and end of timing. Perhaps the driver for that bell could be incorporated into the home automation project from Wednesday. Once the hardware decisions were finalized [Douglas] set out to build an enclosure that he could be proud of (mission accomplished!). Don’t miss the video after the break where he walks through all various aspects of the user interface. Continue reading “Workout Timer Has Its Own Fight Bell” →