Wired News writes:
The mind-boggling speed and reach of Internet search engines mask a severe limitation: They are powered by words alone. But the world is full of objects and patterns. Now computing researchers have developed search engines that can mine catalogs of three-dimensional objects, like airplane parts or architectural features.
All the users have to do is sketch what they’re thinking of, and the search engines can produce comparable objects.
“The idea of information and knowledge, and retrieval of knowledge, has been something I’ve been intrigued with for a long time. This gives it a more solidified meaning,” said Karthik Ramani, a Purdue University professor who created a system that can find computer-designed industrial parts.
Ramani expects his search engine will serve huge industrial companies whose engineers often waste time and energy designing a specialized part when someone else has already created, used or rejected something similar.
With the Purdue search engine, designers could sketch the part they need and instantly see dozens in inventory that might fit the bill.
If an item seems close, but not quite right, designers can see a “skeleton” of the part and manipulate it on their computer screens — make it longer or shorter or curved, for example — and then query the database again.
So how can computer programs look for objects? The breakthrough is the voxel.
Digital camera owners are familiar with pixels — the basic element of a digital image. Each pixel is a tiny grain of color.
Similarly, a voxel is the basic element of a three-dimensional object that is represented in a computer. Each voxel represents the volume of the object at any given point.
In Ramani’s program, for example, stored CAD designs and entries sketched by users are converted into voxels. Then voxel patterns are compared for similarities. Because the voxels represent volume rather than just shape, the program can sniff out, say, a coffee cup, which is mostly hollow but might have a solid handle.