Trickle Pendulum (TP). Details and history.

TP differs from “simple” pendulum, where mass is hanged at a fixed point on a friction-less pivot. TP actually has opposite characteristics. TP mass - “trickler”, has no fixed pivot point. Besides swinging motion about pivot point, “trickler” moves to the new pivot point every swinging cycle. For this reason TP could have another name: “Self changing pivot pendulum”. The other property contrary to “simple” pendulum - TP function unavoidably affected by friction. Abilities to swing and propagate down depend on friction properties of used materials. Therefore reliability of small TPs is not 100% (unless it placed in vacuum). Small TP (meaning small mass) has proportionally small driving moments created by the mass and any kind of obstacles from the environment (humidity, dust particles, human hands oil, etc.) may prevent movement. So, don’t touch “trickler” and holes on the “base” and don’t be upset if “trickler” will stop sometime. Usually it cleans it’s way up by going several times through the path. If it stops it may indicate that environment is dusty or it was touched inappropriately. For toy convenience “trickler” geometrically designed to be permanently attached to the “base.” It can’t be removed without deformation.

It all began with an observation.

For many years I was working designing and developing mostly small mechanisms for variety of industries. And during the course of one simple procedure, where small parts were subjected to ultrasonic bath, I noticed something undesirable, unusual and annoying. Procedure where parts being “C” shape were placed in perforated basket with perforation pattern and size accidentally matching the size of “C”. What was happening - after the procedure several parts would stuck in the middle of the basket perforated surface and there was no easy way to get them out. “C” would not disengage from perforation unless it would be wiggled out to the edge of it. That’s how the base feature of TP - “C-CLAW” was discovered. It described in the patent application, but is not a subject of invention and it can’t be. Based on C-claw properties I developed a concept of warehouse storage system and filed patent application for it. Similar concept of “Vertical parking garage” was presented to “Create the future” design contest in 2010. Still can be seen on the web at https://contest.techbriefs.com/2010/entries/transportation/530 (It was fun to make presentation using several CAD systems).

But development of TP was not finished at this point. The fact that C-claw can move on perforated surface under ultrasonic frequency vibration, made me think that the other source of energy - gravity can work too. From there I theorized the shape of the “trickler” with offset mass (this is patentable) and went through dozens and dozens of prototypes to find out that this seemingly simple mechanism will perform as intended only under very strict conditions of proper mass distribution, high precision, and properly matching materials (low coefficient of friction).

Many TPs of different materials and sizes were made. It was demonstrated that “trickler” can follow not only straight pass down the gravity line, but also sinusoidal wave shape path. This type of TP required even higher precision of parts. Tilt angle of base plate has an affect on a time period of pendulum swing and abilities to move at all. It is easier to make TP to work on tilted back plate, but moving on negative tilt angle plate is possible. This pendulum’s properties are true to the general pendulum theory: swing period of pendulum is longer for larger size TP. Most likely the story of TP will continue to evolve. Some other applications besides the toy may be found. Only three type/size TPs of dozens tested presented on this website.