[CarlS] wanted to develop a low expense x y table for display on teletoyland.com. He realized that to keep expense low, he might use hobby servos instead of stepper motors. exact precision wasn’t a huge issue here, so the hobby servos would be perfectly acceptable.
Though Linear hobby servos are available, he chose that the expense was prohibitive. He used normal hobby servos, however had to modify their internals to get the exact amount of travel necessary. numerous people modify the hobby servos for continuous rotation, however this would cause a loss in the capability for exact positioning. Instead, he replaced the potentiometer that steps the position of the servo with a 10 turn potentiometer. This allowed him 10x the travel.
Using timing belts as well as drawer guides, he constructed the frame as well as motion assemblies. The timing belts were chosen for their inexpensive price as well as no slip building as well as are pulled by customized built pulleys.
The unit is controlled through some PHP scripts, that he doesn’t expand on, through a serial connection to a SSC-32 board. The servos link directly to the the SSC-32. Go ahead as well as give it a try, or view the video to see it in action.