We had our first opportunity to use the sandbox with students in science class this past week. Working with the 5th grade science teacher, Ms. Waid, students reviewed the key elements of topographical maps and explored live changes to topography as they recreated real-life maps in the sandbox. They replicated the Santa Monica mountains and coastline, and rebuilt Crater Lake in Oregon. 

The groups discussed contour lines and intervals, what it meant when lines were closer together or farther apart, and what the different colors on the map represent. In addition to reviewing these core topographical elements, students were asked about water sheds, where local water sheds reside, and how rain water should flow given certain geographical formations. We then ran the rain simulator so that students could test whether their hypotheses regarding water shed locations were true, and discussed the impact of unusable rain water that drains to the ocean, and scarcity of water in times of drought.

Discussion also included the formation of Crater Lake, an existing caldera, and how over time, rain water and snow fall can build up to form a lake.

Below, students are generating rain fall by placing their hands above the surface. At the right height, the XBox Kinect sees these objects differently, and the software is directed to run the water simulator.

I look forward to future classroom uses of the sandbox. Volcanos are a natural fit with this tool, but as new software is developed, I am hopeful there will be many more avenues for inclusion at different grade levels and subject areas.

We hit another milestone today, with the successful configuration of the water flow simulator. It turns out, our first attempts were on a graphics card that couldn't handle the calculations that were required to make the simulation work. We upgraded to an Nvidia GT720 with 1GB of video RAM, and that made the water flow a bit more smoothly. Here are some short clips of the original water simulation.

Next up, on the software side, we will make some modifications to allow for lava simulation. On the hardware side, I would like to integrate USB buttons so that frequently used settings can be accessed with the touch of a button.

The project moved forward this week with the next level of calibration. While the initial Kinect RawViewer application allowed the Kinect to see the perimeter of the sandbox (the X and Y coordinates) and provided a basic level of use for testing the AR Sandbox software, we needed to refine the Z axis calibration between Kinect and the projector to more precisely pair the sand with the projected topographic elements.  Below are some initial views after projector calibration. We dimmed the lights in the room, which gave the sandbox a luminescent appearance.

* For background information on RawViewer and Projector Calibration, see the step-by-step directions from the UC Davis project.

While the initial tests after projector calibration appeared accurate topographically, we didn't feel the look of the sand compared well with what we were seeing online. We decided to add more water to the mixture to allow for shaping the sand in greater detail.

Below are photos after the water is mixed in. Charlie is seen working with a small disc during the projector calibration process. And because word spread quickly that the sandbox was near completion, we had our first class visit. Preschoolers came in to explore the sandbox, learn a little about topography, and receive an introduction to PIRL.

Where do we go from here? There are still some issues to work out with the software, including the introduction of fluid water and lava simulation, which requires the correct video graphics driver. In addition, we are currently connected via VGA, which will be swapped out for HDMI next week.

These past couple of weeks have flown by. With our Spring Musical taking place last week, finding times to meet has been challenging. Rehearsals and special schedules left few openings. However, we were back at it this week for a couple of days.

We've added the Kinect into the project, and began testing calibration. Because of the sensitivity, and need for accuracy in the readings, we stationed the sandbox in PIRL, which may end up as its regular home. The open floor space and smooth, level surface make for an ideal location.

We didn't have time to do a full calibration of the Kinect, using the Raw Viewer application, but did a test run of the sandbox software anyway. I think for both Charlie and me, getting to this point in the project was a milestone. It became real for the first time, as we worked our hands through the sand and witnessed the change in topography as the data was read by the Kinect. There is more work to be done, but this was a huge step forward.

Below is a photo slideshow of the week, and at the very bottom, a short video clip.

The framing of the sandbox is done. We have fastened the support structure for the projector and Kinect, and now need to adjust projector settings precisely before finalizing its position. The sand product that we chose is called Sandtastik, a synthetic material that is safe, non-toxic, and free of silica or quartz. We have 100 lbs. in, with another 50 ready to top off. As suggested by the UC Davis project, we added a bit of water to allow for better sand shaping and holding.

This part of the construction has been challenging and fun. There are no detailed plans for how the framing is to be built, so exact measurements and design are left to each maker. I believe we have a build that is stable and yet flexible enough to allow for minor adjustments. Since we chose to use an older short throw projector (made available after a recent SMART Board upgrade), it is likely that the projector itself will be replaced in a few years. Our design must allow for modification of the support structure as necessary to accommodate different projector models.

With the framing complete, it is time to test out the Kinect. Next week, the plan is to fine tune the projector's position, then mount the Kinect and computer for testing. Everything that I have read about calibration of the software is that this is the most time consuming part of the project. Wish us luck!

We've done quite a bit of work to advance our mobile sandbox structure. During the measuring, cutting, sanding, and fastening of our component parts, Charlie has enhanced his woodcraft and tool use over the past few days. There is only so much you can learn from reading about or watching someone else work with hand tools and machine tools. Ultimately, you just have to dive in and do it. I can see his skills in this area increase by the day, it's all a part of experiencing things first hand.

This week we have measured out, cut and assembled most of our sandbox, including the bottom shelf and casters. We decided to model it similar to a shopping cart, two front wheels that remain straight, two rear wheels that rotate and in our case, also lock. This should provide the most flexible, yet stable, build.

Charlie had the idea of creating a bottom shelf so that we might store sand castle "tools" for the smaller kids to use during their exploration of the sandbox. It will also serve as the location for the PC, keyboard, and any other equipment.

Next week, we plan to work on the support structure for projector and XBOX Kinect. We may also benefit from some type of handle(s) to push the cart when moving from class to class, so that's on the shopping list.

You've seen one online by now I am sure. You may have even tried one out. These are amazing, and seem feasible enough to actually make. What I am referring to is the Interactive Topographic Map Project which originated out of a U.C. Davis project. I first experienced one at the Discovery Cube here in Los Angeles, and was most recently inspired by a colleague at another school whose team built one for their campus. Here's a sample of what this interactive sandbox can do, from the East Carolinian Geology Department:

I am collaborating on this project with an 8th grade student, Charlie. Charlie and I will take the next few weeks to build one for the school. Our objective is to create a sandbox that is mobile, so that it can be used by the upper school science department, primarily, but also by other students and teachers across campus.

The main components for this project are:

• Sandbox and sand
• PC running Linux
• XBOX Kinect
• Projector
• AR Sandbox software and supporting software

During week one, we began building out the frame for the sandbox and setting up the PC with Linux and AR Sandbox software. We were able to get much of the materials for free or very low cost, but I did purchase the PC new in order to have the faster graphics card.

Pictured above, Charlie is measuring out, cutting and sanding the framing. Once set, wood glue was applied to the frame, and the base was screwed into place.

As recommended by the originators of this project, we are using the Linux Mint distro for this project. Interestingly, the Linux Mint site was hacked into during this same week, so the site was down temporarily until they could ensure a safe new version. This was the first attack of this scale that the organization had experienced.

Next week, we will continue work on the mobile part of our sandbox and hopefully have time to test the Kinect.