How to Make a Camera Dolly
Using a dolly for motion camera shots is likely a little out of the norm for home movies. For tracking motion or creating perspective motion in a video shot, it's an absolute must because you can't get a smooth sequence without a dolly. In most cases a camera dolly consists of a platform with a tripod mounted camera and seat for a camera operator elevated on a track to obtain smooth precise motion along the path of a planned shot in a video sequence. While doing some online research for a little video project I want to create, I ran across several inventive solutions for do-it-yourself dolly rigs from common parts available at the local hardware store (or possibly the local skate shop).
For tracking a shot in a confined space like a large room, a dolly mounted on a small track like the one at Andersson Technologies, pictured here is likely an easy solution. If you ran a track on the ground using this type of setup, you could build a path to emulate a dog's or cat's eye view perspective run through the house. The hardest part in shooting is likely keeping the track out of frame because you're dealing with potentially narrow entryways between rooms.
In larger spaces or for outdoor shots, building a track using a combination of PVC, skateboard wheels and a plywood platform creates a dolly large enough to support a person, a tripod camera mount and a way to power the dolly for smooth motion throughout an entire shooting sequence like the two examples below. It appears the more detailed directions from Joren Clark are essentially the same dolly stucture as what's found in the Matt Hawkins How to Make a Dolly schematic, although I have no idea which came first.
Regardless of the size of your dolly, keep in mind that you need extra track to build up momentum to get smooth video throughout the motion shot with enough extra track at the end of the run to avoid running out of track before your shooting sequence ends.