Tracking time in the Internet of Things

By mvuilleu, in Measures and Internet of Things, june 21,2015.

In an computer system, measure and event timestamps are considered an evidence and, nowadays, no one expects to encounter difficulties in this domain. However, knowing the exact time at any time is far from obvious, in particular if you work with autonomous sensors with limited resources.

Using Emoncms on a private server

By seb, in Measures, june 10,2015.

A few months ago, we explained how to configure a YoctoHub or a VirtualHub to automatically post sensor values on emoncms.org. Emoncms is a web site which allows you to store measures in the cloud and to display them prettily. There are numerous sites which offer this kind of services (either free or for a fee), but Emoncms is, to our knowledge, the only one which is Open Source and which can be installed on a private server. And this is exactly what we are going to do this week.

Viewing temperature flows

By mvuilleu, in Reviews and Measures, june 07,2015.

Summer is coming and, with it, heat waves that put a strain on the air conditioning of server rooms. How can we know if an air conditioner is of the right size or if it labors to cool the room and risks to fail at any time? How can we know if fresh air is distributed everywhere, or if the addition of a simple air circulator could save a few KWh?

YoctoHub and Web-Applications

By martinm, in Programming, may 29,2015.

As you may have noticed it, all Yoctopuce modules are essentially peripheral devices. Sensors provide values, actuators perform explicit actions, but the actuators cannot automatically activate themselves depending on conditions on the sensor values. In short, there is no room for any kind of user logic in our modules, you need a CPU somewhere to drive your modules. Why not use that of a web browser? It's quite possible to host a Web-App on a YoctoHub. It's a technique that we have used before, but never really took the time to explain...

Creating crystals

By martinm, in DIY, may 22,2015.

One of us recently bought one of these scientific kits for children. Yes, at Yoctopuce, we still are big kids :-) The idea was to grow crystals, but frankly the result wasn't very convincing. We ended up with a pile of ridiculously small crystals at the bottom of a plastic cup. Nothing like what was promised on the box. We wondered if we could better the concept with some Yoctopuce modules. Let's see if we can do as well as Walter White...