If you have been following the development of Google Maps over the years, you are probably familiar with the Trekker, the backpack that includes a complete Street View camera setup for mapping anything from hikes into the Grand Canyon to walks through penguin colonies in Antarctica. On Thursday, a new backpack is joining Google’s mapping tools: the Cartographer for indoor mapping. The Cartographer uses a process called “simultaneous localization and mapping” (SLAM), a technique that’s typically used for mapping new locations and that Google is now putting to use to map anything from hotels to museums. As the backpacker walks through a building, the floor plan is automatically generated in real time, Google says. The wearer also uses a tablet to add points of interest while walking around the building (say room numbers in a hotel or the exhibits in a museum).