Joe Polastre: August 2008 Archives

What do 15,000 Java developers have in common? Besides a love of object-oriented programming languages and an oddly-shaped mascot named Duke, Java developers act en masse. How do we know? Sentilla was commissioned by Sun Microsystems to instrument the Moscone Center in San Francisco with over 200 pervasive computers during the 2008 JavaOne conference. Sun wanted to have greater insight into the behavior of attendees during the conference so that organizers could adjust energy-usage in real-time and better plan for future events. Each morning, John Gage presented Sentilla's findings. At the close of the conference, he exclaimed, “We have enough data to establish new patterns of behavior.” For instance, Gage and organizers from Sun were able to correlate the actions of the attendees to spikes in resource consumption, coming up with ways to save significant amounts of energy. Gage insists that all future conferences at Moscone -- whether from Sun, Apple, Microsoft, Oracle, or others -- should use Sentilla's solutions to minimize their environmental impact.

By knowing how and when people use a building's resources, energy usage can be tightly controlled. A new application brief from Sentilla discusses the impact of intelligent management, using resources exactly when and where they're needed rather than the wasteful practice of keeping everything on all the time.

Read the application brief >>

This entire application was built by Sentilla's engineers over the course of a couple of months using the Sentilla Software Suite and some custom hardware. We counted each person that entered or exited each room and monitored the environmental conditions including temperature, humidity, and light. Not only did we know when resources were in use, but we could also gauge the popularity of each session. Jonathan Schwartz, CEO of Sun, told EVP for Software, Rich Green, "That's going to be your performance review for the year. I want to make sure that everybody stays throughout the session, and you'll get a pass."

Dual infrared emitters and transmitters were mounted to each doorway in the Moscone Center (shown to the right). The devices analyzed the patterns by which each infrared beam was broken to determine the direction a person is walking and count each entrance and exit. The devices were mounted using magnets; the units snapped right onto the doorways in seconds and removed quickly at the end of the conference without any impact on the facility. Additional pervasive computers were placed on the stages and in the audience to analyze the humidity and temperature. With these sensors, the analysis showed each time that the H/VAC system turned on to cool the room, and the frequency of H/VAC events was correlated with the quantity of people in the room. Light sensors also showed us when the lights were left on (for example, in the evening), and even the start and stop times of each technical session.

The data was brought back to a webpage, and shown in each morning's keynote presentation. Below is the data from the first day's keynotes, where you can see the first keynote had strong attendance while the second keynote occurred while other sessions were in progress and thus had more flux.

Further data shows us the environmental conditions in a session room. Using the temperature, you can see the H/VAC cooling events. Using the light sensor data, you can see the changes in light as each session starts and stops.

Want to know more? Read the app brief, now available on our website.

If you haven't been religiously hitting the reload button at the Sentilla Developer Forum, then you might not know that we've released Sentilla Software Suite version 1.1.1 for multiple development platforms. I switched to Mac early this year, and I was waiting with bated breath for the native OS X development environment. It is now here, with all the features available on the Windows version. And if you're a Linux guru, we also have an Ubuntu Beta release.

Included features of Sentilla Software Suite 1.1.1 for Mac OS X, General Availability (GA) release:

• Full Java compliance with CLDC 1.1
• Native Sentilla Work IDE
• Firmware burning for both gateways and motes
• Sentilla Hostserver for OS X for managing mote applications
• Samples, tutorials, and cheat sheets
• Download and run applications from Sentilla Labs

We received a ton of requests for OS X at JavaOne. We quickly released a Beta version, and now the full GA version is available. It is compatible with your Perk kit, whether you bought it at JavaOne or our online website. Sentilla Labs applications can also be downloaded and used with the OS X release. Go to the forum, download the Sentilla software update, and enjoy the native OS X goodness!

As mentioned in a previous post, the last couple of months have been filled with tons of developers talking to me about their ideas for pervasive applications. Sentilla has been busy building applications for large industrial customers, working to increase efficiency and decrease costs. But every once in a while, we come up for air and build some fun pervasive applications that we deploy in our world headquarters. With all of these applications, most with only a few lines of code, I started wondering: where should we put them?

This thought process has led to Sentilla Labs, a new website launched today that showcases all of the different applications that our developers are building. Sentilla Labs is full of developer-contributed applications (developers retain the rights to their ideas and code) with details on how they built the application, which sensors were used, and even code for you to download and try it out for yourself.

I categorize the applications on Sentilla Labs into three buckets:

1. Bite-sized versions of large-scale industry applications. One project is a refrigerator monitor. It uses two pervasive computers -- one inside a refrigerator and one outside -- to alert us when someone leaves the fridge door open. The same application has been used to retrofit large industrial refrigeration systems to save energy and control temperature.
2. Developer applications and prototype hardware. If you've wanted to set up a sensor to detect when your kids come home late at night, here's the plan. The Motion Detector project uses a Radio Shack infrared detector to alert you when there's movement. Think of it as a programmable home security system. You could extend it to turn your lights on and off, just like in your office.
3. Fun applications. No software product is complete without the presence of a game. And what game is more fitting than the classic, Pong. Built using accelerometers in the Sentilla Perk kit, two people go head-to-head and the score is shown on their pervasive computing "paddle". One of my favorite applications to demo!

Everything is built using Sentilla Perk which is available for $199. The kit comes with the full Sentilla development environment for pervasive Java, and you can download the code from Sentilla Labs and run it in a few minutes. Be sure to contribute your ideas back, we'd love to see what great things you've built.