An Undulator is a reciprocrator "on steroids". The key difference is that one of the cams is replaced with another which is not round. There are many shapes, many with shapes like a rosette.
These cams are similar to the oddly shaped cams or gears in a Spirograph, and similarly amazing shapes can be thusly produced.
Books and Papers
- Hotzapffel, Volume VI by John Edwards. John compiled a great amount of information about this device, starting on pg. 521. The drawings of various cams and associated waves produced explain this topic far better than I could.
- Scott Barrett gave a demonstration to the club about his undulator. The recording for this video is in the Ornamental Turners Int'l (OTI) member meeting videos, August 2023.
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