Category: 3D Print Models

Summary
Yet Another Poor Man’s Handheld Brushless Gimbal
Ever since I got the Mavic pro i haven’t been using my home built drones for aerial photography anymore. So I figure I’ll turn my cheap chinese 2 axis brushless gimbal into a handheld one so i can use it when i go traveling.
I’ve looked at the other designs on thingiverse but i didn’t like that they all left wires hanging about in the open. No offence to the other designers… I wanted one that would look much cleaner and travel better without having to worry about wires snagging on stuff. So I set out to design my own.
I designed this to be used with an EKEN H8 Plus and action cam with the same body format as Gopro Hero 3.
This design makes use of contact adhesive to glue the parts together and requires soldering and basic electronics skills. Some filing and fitting of the parts may be required. Do not attempt if you have a problem with any of the above.
Print Settings
Printer Brand:
Prusa
Printer:
i3 MK3
Rafts:
No
Supports:
Yes
Resolution:
.20
Notes:
Infill doesn’t matter as most of the parts are “thin wall” so most slicers would automatically do 100% fill anyways.
I printed this in PLA and the parts fit quite nicely. Where it’s too tight i used a file or sand paper to open it up a little. if printing in ABS it will shrink and make it too tight for the motors to move freely, so scale it up appropriately. I haven’t printed this in ABS so i can’t say how much to scale up.
Post-Printing
0. Required parts
Printed parts
No name chinese 2 axis gimbal like this one https://goo.gl/GvutmB
Mini rocker switch like this one https://goo.gl/tPpHTY
RC radio battery like this one https://goo.gl/znMdYC
JST connectors like these https://goo.gl/r9qnca
4 M3 x 14mm bolts and nuts, i recommend just getting a box of assorted ones like these https://goo.gl/eiZ4qW
Heat shrink tubing to fit over the legs on the power switch
Contact adhesive to glue PLA parts together
1. Disassemble the aluminium gimbal
Disassemble the aluminium 2 axis gimbal.
Remove all the header pins and the JST power connector on the control board.
I chose to eliminate header pins to make it more compact, the motor wires will need to be direct soldered to the pads during assembly. Make note of which wire connects where if necessary.
2. Remove support material
Remove support material from the parts. The support material inside the wire ways is a pain to remove; some spit grit and good ol’ elbow grease may be needed here.
It may be possible to print the motor arms without supports, but that will depend on your particular printer’s abilities with overhangs. i opted to go through the work of removing support just to make sure everything comes out right.
Take this time to ream out all the bolt holes with a drill bit.
3. Glue parts together
Apply contact adhesive to flat flared part of the part named “handle” and glue it to the flat side of the part named “bottom case”. Try to get the back edge to line up and left right centered on the bottom case. I measured the distance on each side and marked the position by scoring with an exacto blade to help me position the handle.
Take the part named “top case” and the part named “roll motor”. Use a file and an exacto blade to get the mating surfaces free of residual support material and as flat as possible. Apply contact adhesive to the indent in the top case around the opening and glue the “roll motor” part to the top case.
Take the parts collectively named “camera mount” and glue the two larger parts together. refer to the pictures to see how it’s supposed to go together.
The little “M” shaped clip is to hold the IMU sensor in place and will be needed during assembly.
Set aside and allow adhesive to cure.
4. Mounting the motors
Take the IMU sensor liberated from the aluminium gimbal and disconnect the cable on both ends. Feed the cable through the wireway in the part named “pitch motor”.
Take one of the brushless motor that was liberated from your aluminium gimbal, feed the motor wires through the part named “pitch motor” from the opening with the 4 hole bolt pattern and mount the motor with the 4 M3 screws that came with the original gimbal. You may choose to use other bolts, but be careful not to choose ones that are too long as it will damage the motor windings.
The parts was designed such that where the wires comes out of the motor points directly down the wireway. There is a gap between the motor and the edge of the opening on the inside face of the arm to accommodate free movement of the IMU sensor cable.
Now take the “pitch motor” assembly and feed the motor and IMU sensor wire through the gap between where the other motor goes on the “roll motor” part and then down the wireway and through the opening in the top case.
Take the other brushless motor and feed the motor wire down through the wireway the same as the other wires and mount the motor onto the part named “roll motor”. Also mount the pitch motor assembly to the roll motor.
Rotate the assembly throughout its range to ensure there is enough free play such that the wires are not strained from the movement. I used tweezers to reach in and pull some wire back into the wireways so that there’s some slack to allow for free movement.
5. Wiring it up
At this time the control board should be relieved of its header pins and power connector.
Solder a JST female connector to the mini rocker switch in series on the negative (black) side of the wire. Put some heat shrink tubing over the legs on the switch to give it some protection. Now feed the wires coming from the switch through the switch opening on the handle and snap the switch into place. bring the wires to be soldered onto the control board up through the bottom case opening and solder them to the control board.
Observe correct polarity as there is no diode protection on these boards. A mistake here could let out the magic smoke and render the board defunct.
Now take the top case/roll motor/pitch motor assembly. There should be 3 sets of wires dangling down from the top case wireway opening as follows
IMU sensor cable
Roll motor wires
Pitch motor wires
Cut the connectors off the motor wires, strip the wires and solder onto the corresponding solder pads on the control board as noted in step one during disassembly.
6. Affix the IMU sensor, camera mount
Place the IMU sensor into the slot on the camera mount and install the “M” shaped clip. The IMU sensor should be affixed into place. Run the IMU sensor cable along the space around the motor and connect to the IMU sensor. Mount the camera mount onto the pitch motor with the 3 screws that came with the original gimbal.
Rotate the camera mount assembly 180 degrees and ensure there is enough slack in the IMU sensor cable to allow for free movement.
Connect the other end of the IMU sensor cable to the control board.
7. Apply power and test
As i didn’t design an opening to allow for USB connection for PID tuning, at this point i recommend connecting the battery and testing before final assembly.
Just like tuning the gimbal on a drone, the action cam should be installed in the camera mount for weight balance.
8. Case closed
Use 4 M3 x 14mm bolts and nuts to assemble the top case and bottom case assembly together with the control board in between. The top case was designed with enough space to hide all the wires inside without pinching them, but do be careful not to pinch any in between the bolt posts.
Now the gimbal should be ready for action. Connect the battery and shove it up the handle, shove the extra wires and connects from the battery in the free space around the battery. Snap in the pommel cap. The positioning tabs on the cap may need to be filed down a bit for an easier fit.
Enjoy.