Creep 2.0 - Tricopter
Building on the success of the Creep 1.0 Tricopter, here is the newly designed Creep 2.0. Airframe is made of laser cut light plywood, nylon motor mounts and arm clamps produced in a 3D Laser Printer (Laser SLS ) and 450 heli tail booms.
-Airframe parts are laser cut or laser printed
-DT-750 motors are modded with thrust bearings for maintenance free flight
-1.9 lbs. total weight (configured with Paris Wii, AR8000 Receiver and TM1000 telemetry unit)
-Airframe has pre-cut holes for Paris Wii board
-Arms are standard 450 heli tail booms
-Yaw mount is mid frame and entire rear arm rotates on precision bearings for smooth operation
-All three motor mounts are identical/interchangeable
-Rear motor sits as the same height as the front motors for more uniform control
-Nylon arm clamps and motor mounts naturally absorb motor vibrations so no extra vibration dampening hardware is required
-All motor/ESC wiring is internal to the arms for a super clean look
-Custom wiring harness allows for motors, ESC or entire arms assemblies to be removed and replaced easily and quickly
-Arm clamps and motor mounts can also work for a quad, hexa or octo copter. Motor mounts can be set at any angle to help with poor yaw tendencies of hexa and octo copters (no need to add expensive angled shims)
It all started with a CAD drawing.
Files are emailed off and airframe parts are produced. (this is actually the first design but they weren't good enough. A redesign was done and parts reordered)
Airframe parts are painted.
DT-750 motor mounts are installed with nylon screws and nuts. Screw heads are blackened with a Sharpie.
Skids and arm clamps are mounted on the main board. Arm clamp screws are installed from the bottom during the wiring and electronic install process.
Nylon standoffs for the Paris board is installed. NO EXTRA ANTI-VIBRATION HARDWARE REQUIRED.
The heli booms can be used "as is" if a stock gyro only configuration is used, but if a Paris board is used then the rear arm needs to be cut 18mm so it will sit flush with the inside of the arm clamp like the front arms do.
Here is a gyro/Flymentor install where the rear arm does not have to be cut.
Test fit of Paris board and arms.
Wii components are installed on the Paris board and then installed on the nylon standoffs.
The top plate gets the receiver, servo and telemetry unit installed and a custom wire harness made for the receiver.
The rest of the wiring is completed to include the battery to ESC wires.
Here's a great photo of the rear arm, yaw assembly and the wires that travel through the rear arm. The entire arm will rotate.
Wiring/connections are prepared at each motor mount. The ESC signal wire connection will be tucked into the end of the arm. The small red and black wires will be cut off except on the rear arm. The rear ESC BEC will power the electronics.
The top plate is installed on the upright screws. Then one by one each screw is removed and reinstalled from the top.
The excess screw length is cut to allow the battery mount to be installed and reduce weight.
All the screws are installed with a nut, tightened and then blackened. Here you can see the blue wires that make up an umbilical chord for the USB programmer.
Receiver wiring harness is connected to the Paris harness.
Motor and propellers are installed. Wiring is tidied up. Motors are modified with thrust bearings that won't wear out like the stock ones. (Note: this same motor mod reduced current draw by 3 amps on my quad and makes the motors wicked quiet ).
Here is the rear motor and mount. It is identical to the front motors except for the 2 extra (red and black) wired that run from the BEC to the electronics.
The battery mount is installed.
The canopy magnets are epoxied onto the top plate and the canopy. Here, extra magnets hold the canopy magnet in place while the epoxy dries.
The servo wire is cut short and a connector is installed. This allows for the top board to be removed much easier.
Thanks HK for laser engraving my tail boom!
Weight = 1.9 lbs (configured with Paris Wii, AR8000 Receiver and TM1000 telemetry unit)
Last edited by johnorama; Jul 19, 2011 at 07:42 PM.
DT-750 Motor Mod
I do want to share the bearing modification that I am using. After all the help I have received from others in the Tricopter community, it's the least I can do to give back. When I do the next mod I will photograph the steps but for now, here is the short version.
The heart of the mod is a 4x9x4mm thrust bearing. You need to add this to the bottom of the motor. Here are the basic steps:
1. dismantle the motor
2. loosen the set motor shaft set screw on the motor bell
3. use a small file to flatten a spot on the motor shaft 4mm above the point where the set screw currently makes contact with the shaft.
4. push the motor shaft down at least 4mm
5. lubricate the stock bearings
6. reassemble the motor just like it was but do not install the bottom e-clip
7. slide the thrust bearing onto the motor shaft at the bottom of the motor and lubricate it
8. install the e-clip
9. thread a 4mm nut onto the motor shaft all the way to the bottom
10. tighten the nut slowly until the e-clips removes all the slop from the thrust bearing. Spinning the shaft will cause the bottom race of the thrust bearing to spin twice as fast as the middle bearing when installed properly.
11. tighten the motor shaft set screw
12. remove the 4mm nut
13. don't over tighten the prop nut or you could compress the thrust bearing. I install an upside down flange nut finger tight first, then the prop and then another flange nut. Then tighten the top flange nut while holding the bottom flange nut.
Note: this only works with the newer style DT-750 motors
|Category||Thread||Thread Starter||Forum||Replies||Last Post|
|New Product||Tricopter - The "Creep 1.0"||johnorama||Multirotor Talk||439||May 16, 2012 10:24 AM|
|Discussion||12FG Software version 2.0/2.1 Manual Needed||skyboyken||Radios||2||Jul 02, 2011 01:30 PM|
|Build Log||Tricopter v1.0||3qUInOc||Multirotor Talk||10||Dec 28, 2010 12:04 AM|