Lately we've seen some really interesting applications that depend on devices that have sensor hardware such as accelerometers, light sensors, touch sensors, and global positioning system receivers. Most of the innovation has been on mobile devices such as the iPhone. With Windows 7, Microsoft is trying to make sure it won't miss this party.PCs have had sensor hardware for several years. For example, some ThinkPad notebooks have an accelerometer that detect when the notebook is falling, and they quickly park the disk heads to prevent damage. (After all, it's not the fall that damages the drive, it's the sudden stop at the bottom.) Several models, including ones from Dell and Asus, have ambient light sensors that can automatically adjust the screen backlight based on the room lighting.

Although these sensors already are present in many PCs, they've been used mainly by the hardware makers and not easily available to software developers or users. That's because they tend to be proprietary interfaces that work differently on each PC, and they often require low-level hardware access. There are no Windows interfaces that allow either the operating system or applications to use these sensors in a standard way. That will soon change.

At both the Professional Developer Conference and Windows Hardware Engineering Conference last month, Microsoft was exhorting both hardware and software developers to take advantage of new Windows 7 interfaces that make it easier to integrate sensors. They will standardize and simplify the way sensors are interfaced to the system and give users the ability to control which applications are allowed to use a particular sensor. Games, for example, could take advantage of the accelerometer to react to the motion of a notebook.

There's a great overview of all the new sensor-related information at Microsoft's Windows Sensor and Location Platform page. To further encourage its use, the group responsible for evangelizing these interfaces was liberally distributing a Sensor Development Kit at the conferences. It's a small circuit board with a USB interface that provides access to the board's accelerometer, light and touch sensors, plus software and documentation.

Although it's great to see these innovations for Windows 7, I'd love to see Microsoft make this new sensor interface available for Vista and XP. Otherwise we'll be in the classic chicken-and-egg situation where neither software makers nor hardware vendors see enough near-term benefit to justify the expense. This is just too cool to let that happen. Let's not wait for Windows 7 before we see this technology in action.