Over these past few months, I have slowly been testing out various materials for absorbing vibrations in the Revision III tricopter. The goal was to eliminate the rolling-shutter effect (or jello-effect) from aerial video as much as possible.
If you don’t already know, this tricopter has its battery and camera equipment suspended from the main frame with three zip-ties. Dampening materiel is loosely compressed or adheared between these two subassemblies and is ultimately responsible for most of the physical vibration isolation. Usually this materiel is rolled into three separate ~1″ long by ~5/8″ wide cylinders and stuck between each of the three zip-tie loops.
Among the materials I have tested include vinyl furniture bumpons, Sugru blocks, double sided foam (vinyl) adhesive, and latex foams among other things. Most worked pretty well, but others were hard to come by or showed poor performance.
Here is a short list of my findings presented in a general order with the best (so far) near the top. Continue reading Obscure vibration dampener material tests for the Rev. III Tricopter
It’s alive! The tricopter went under a few more revisions and prints before finally taking to the air. My old Rev One Quadcopter has been reduced to it’s (over-engineered) frame and nothing more. Its parts (motors, ESCs, batteries, Crius AIO, etc.) have moved on to become this very tricopter.
Currently (in the picture) it is set up to fly FPV sans-GoPro. There is an optional part available to replace the camera pan/tilt servo mount/hole with an alternative “use-what-you-want” vibration-dampened plate.
Keep reading for a couple closeups and highlights of the tricopter.
Continue reading Tricopter Build Log part three
The frame is now prototyped and measurements are almost final. Several small changes were made to the source files as result of this prototype (now on internal-revision #24). These changes included primarily wider tolerances and smaller hardware requirements. Other potential ideas are still pending (in particular; optional “taller” landing struts, ESC/wire management, and AIO mounting).
Changes to the last update included primarily, universal motormounts. Now it’s not necessary to use a specific cross plate on a limited range of motors. I’ve adopted the standard 16/19mm hole spacing used on many motors appropriate for this size multicopter. Also, the mount’s face is now flat on both sides, so you can more easily mod them (drill holes) for a specific motor that doesn’t follow these standards. With this, you will need to use 8mm M3 socket cap screws (instead of the shorter, countersunk M3 screws often provided with your motors) to mount said motors to the mounts.
The arms fold back too!
Continue reading Tricopter build log part two
The frame still needs to be prototyped on my printer, though I have modeled the finished project to get an idea of the size.
The distance between motor-centers is roughly 625mm when the two front 1/2″(12.7mm) wood dowels are cut to 350mm and the tail to 310mm (-40mm). This was necessary to accommodate the inline motor hinge that pivots on the axis of the tail arm. These dimensions, along with other things, are subject to change after the prototype gets printed.
I modified Thingiverse user ennui2342’s tricopter body, based off of David Windestål’s RCExplorer tricopter, to support the stronger, more common 1/2″ wood dowels. Other minor modifications to the body were made as well. I also loosely based my landing gear/motor mounts off of jphillips’ designs. The shock absorbing bottom plates (optional setups for FPV shown above) are unique to this tricopter.
Continue reading Tricopter build log part one
At this point I still need to print and test the frame as well as make a shopping list (1/2in^2 wood dowel, wire, connectors, lights etc.). Currently waiting for new high-quality pulleys for my printer.