At the top of each hour, a proprietary controller sends a signal via RS-485 link to twin controllers, causing them to execute a motion profile program that drives each of two sculptures. A NEMA 34 stepper motor running in the open-loop mode in conjunction with a 15:1 right angle gearhead provides enough torque to drive the system. An open gear reduction of 5:1 between the gear-head output pinion and the slewing ring gear on the stage platen maintains a favorable inertia ratio between the rotating sculpture and the motor. This configuration allows the system to accelerate the sculptures at approximately 1 rev/sec2 to speeds in excess of 20 rpm when executing their motion profile. The completed rotary stage is repeatable to ±2 degrees, with most of the position error due to backlash in the open gearing comprising the final stage of the drive train. The easy programmability of the ZETA system allowed for a dynamic and realistic motion profile.
The fun factor continues to draw developers to Linux. This open-source system continues to succeed in the market and in the hearts and minds of developers. Design News will delve into this territory with next week's Continuing Education Class titled, “Introduction to Linux Device Drivers.”
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.