Most video jibs that we share have a similar design, they are build with dual bars. It is those dial bars that keep the camera in the same orientation no matter how you tilt the jib. Think those ancient desk lamps.
The Wooster Sherlock design by Noack is kinda different, and is more like the CobraCrane Single Bar series where jibs only have one bar and a parallel wire that keeps the camera in a constant orientation.
The bar is basically a Wooster Sherlock painters poll, which is how the jib got its name.
The clever part is using K’nex gears to control a plate that is on the other side of the poll. The gears make it possible to create a tilt movement right from the base.
Here is a small demo of the jib.
For complete build instructions visit the original post over at Instractables.