|Finished camera dolly made out of Makeblock and plywood. The plywood is painted black with a regular (alkyd) spray paint.|
Makeblock claims they have an open source hardware and software platform. Makeblock uses an Arduino clone, called Baseshield, and Arduino is truly open source software platform. The Baseshield uses the RJ25 a 6 pin connector (known for their use in telephone lines) to interface with their sensors. Although this RJ25 is easy to use it is not so easy to connect a generic electronic component to it. This can be avoided by just replacing the Baseshield with a regular Arduino (EDIT: something I haven't done in this project). Furthermore Makeblock provides free downloadable CAD drawings of their mechanical parts such as the beams and gears.
I found an example of a Makeblock camera dolly in the internet but unfortunately no documentation was provided. I therfore had to improvise using the Makeblock components that I had. My Makeblock dolly also has four wheels and only a couple of beams are needed. It is very sturdy. It uses two 6V motors that came with the starter set. Each engine has a simple transmission to a wheel via a belt and a couple of gears. The combination of the gears reduces the speed of the motor.
I needed a solution to attach the camera to the Makeblock beams. I decided to make a plywood frame for the camera since I have a lot of plywood lying around. Plywood is cheap but strong enough for this application. With this plywood frame the camera is able to tilt up and down and rotate. With the bolt and nuts I can fix the camera in a desired position.
|The plywood frame that serves as a mount for my Xacti camera. The frame is made out of 1/2" thick plywood cut in strips of 1-1/4" width. The frame is assembled with 1/4" bolds and nuts.|
|The camera mounted on the frame.|
|I had to place the camera a bit outside the frame to be able to open the display.|
I could have used any other material to make a camera dolly than Makeblock but that would probably have taken considerably more time. On the other hand using wood or plastic is much cheaper. The aluminium mechanical parts are fairly expensive. Some Makeblock parts can easily be replaced by cheaper alternatives. For instance all screw are 4 mm screws which can be bought at the local hardware store. Same goes for shafts and nuts.
|The dolly in action with the still unpainted frame.|
All in all I'm happy with the result although the dolly still needs some work. First the dolly has a slight tendency to move to the left. I exchanged motors, gears and wheels from left to right but that didn't made a difference. Also the dolly has no suspension at all which can lead to unstable video's.
I added a YouTube video below to demonstrate the camera dolly.