Thursday, December 28, 2017

Converged Drone Developer's Platform

I install the most popular 250 sized racing quadcopter's motor on the most popular hobby helicopter for IOT/MQTT/COAP research, and see what happens. 3S, 11.1 volts lifts the 240-249 gram(including Raspberry Pi Zero) take-off-weight at less than 4/6 throttle. The fuselage is Blade 230 sized heli(Blade BSR) body. Tail motor is the popular 1306 sized 3100kv intended for 130 sized quadcopters, tail prop is bull-nose cut from a 5040 prop , which produces counter torque thrust of 33 grams for cruising. Rotor head and blades are 210 sized helicopter parts from Oxy2 helicopter.

The helicopter fuselage is cheaper, at less than 7 dollars including shipping. The quadcopter motors and props are cheaper. The complexity of the system is about the same as a quadcopter with 4 pairs of folding blades. Either this helicopter, in direct drive configuration, or DJI Mavic Pro has exactly 16 moving parts of the vehicle. They are the main motor, tail motor, 3 CCPM servos, 2 folding blades, 2 grips, 2 halves of the swashplate, 5 linkage rods. And on the DJI Mavic Pro, they are 4 motors, 4 folding arms, 2 folding blades for each motor. So, the math is 2+3+2+2+2+5 = 16 = 4+4+2x4 .



My goal is to do a Trump tower diving with it, like this video below,

The cost is about 1 dollar per gram, including shipping cost, break downs in the bottom table. Shipping discount for multiple items from a vendor has been applied. No volume discounts are used.

The entire craft can be built without a machineshop. All built in my car while waiting in traffic and in between commutes. Only used light hand tools and light electric tools that can be powered from car battery.



CC3D configuration for LibrePilot 16.09+dirty is at https://drive.google.com/file/d/1S_8A7ODSe-Kncj7hl1GtejdZaLcz_qwL  And the flight video is below,

Sunday, November 19, 2017

Hybrid Drone Developer's Platform

Why can't drones do good for people?


I use the following direct-drive, sub-250-gram helicopter for IOT/MQTT research. See attached pictures. 4S 14.8 volts lifts the 249 gram(excluding Raspberry Pi Zero) craft with 2806 sized motor. The fuselage is Blade 230 sized heli(Blade BSR). Tail motor is 1306 sized 3100kv, tail prop is bull-nose cut from a 5040 prop , which produces counter-torque thrust of 33 grams for cruising.

The result is a combination of quad copter and helicopter. The helicopter fuselage is cheaper, at less than 7 dollars including shipping. The quadcopter motors and props are cheaper. The complexity of the system is about the same as a quadcopter with 4 pairs of folding blades. Either this helicopter or DJI Mavic Pro has exactly 16 moving parts of the vehicle. They are the main motor, tail motor, 3 CCPM servos, 2 folding blades, 2 grips, 2 halves of the swashplate, 5 linkage rods. And on the DJI Mavic Pro, they are 4 motors, 4 folding arms, 2 folding blades for each motor. So, the math is 2+3+2+2+2+5 = 16 = 4+4+2x4 .



The cost is about 1 dollar per gram, including shipping cost, break downs in the bottom table. Shipping discount for multiple items from a vendor has been applied. No volume discounts are used. The on-board computer is not included in the calculation.

My goal is to do a Trump tower diving with it, like this video below,
, using the alternative small prop blades noted in the breakdown table to evade authorities. And then the craft can perform military and industrial applications when using the proper prop blades with Raspberry Pi. 


And this setup allows forward compatibility when old helicopter parts run out and future replacements come. In the following picture, the fuselage, swashplate, and anti-rotation bracket are replaced with Blade 230s parts. The trick to allow different sizes of control balls to fit the 180 CFX main grips is at the DFC linkage. The threaded rod and the lower half of the linkage is the servo rod of 230s for 230s swashplate, while the lower attachment is the pitch control attachment of the BSR for BSR swashplate. The helicopters in either configuration look identical in the side view.

Sunday, August 6, 2017

Keeping Your IOT Drone Under 250 Grams


Nothing requiring government registration can become mass consumer product

So are drones. Helicopters offers better hover duration than quads. But, Blade 200S is moving away from the 250 gram realm of Blade 200SRX. Luckily there is a quick fix. Use Blade 200SRX and common quad parts on top of the 200S body. And I reduce it to 236 grams. The weight reduction is 1.7 grams from common quad components tail section, 1.6 grams from home-made ESC-BEC, 3.6 grams from Xtreme 8-degree blades, 3.4 grams from EC2 2mm banana plugs, 2.3 grams from Microheli main shaft, and 2.1 grams from removing battery strap and jacket. The 200S body gains 2.3 grams . CC3D Revo Flight board with FS-A8S receiver make the electronics reduces 0.2 grams weight from stock AR636H +AS3X .
246.6 - 1.6 - 3.4 - 3.6 - 2.3 - 1.7 - 2.1 - 0.2 + 2.3 = 234.0
Comparison to stock components follow,

Modified
256.8 - 22.8(stool) = 234

Stock
202.1 + 68.9(battery) - 24.4(stool) = 246.6
.

Breakdowns of the weight loss

The tail weight is 2.6(fin+screws) + 17.5(motor+mount+wires+screw+prop) + 3.8(boom) + 0.7(female part of 2mm EC2 banana plugs) = 24.6 . The stock tail weight is 1.9 (fin+screws) + 17.9 (motor+mount+wires+prop) + 2.9(boom) + 2.5(support booms) + 0.4 (horizontal fin) + 0.7 (male servo plug not pictured) = 26.3 .
Modified
Stock
The kit has a standalone shaft tightening bolt (upper left corner). But the kid does 
not need prop holder because the push configuration presses prop down.
Stock does not have separate tightening bolt.

Second layer breakdown of the motor+bracket+wires+screw+prop in the tail section follows.






Prop is 0.2 grams lighter in my modification. Motor is also 0.2 grams lighter then stock.

ESC without main banana plugs is 16 - 0.7 = 15.3 . Stock ESC without main banana plugs is 19.4 - 2.5 = 16.9 .




Xtreme blade has hollowed body underneath the decal skin.



EC2 2mm banana plugs is less than 1/3 the weight of stock 3.5mm banana plugs





Carbon fiber main shaft is less than half of stock steel shaft.




Battery strap and jacket removed from stock configuration


New 200S's body gains some weight



Here the retail AR636 is 11.5 . CC3D(8.8)+A8X(2.5) is 11.3 .


. And CC3D settings follow,








. The bug in CC3D prevents me from using vehicle type "FP" fixed-pitch. If I select FP, INPUT in the flight data tab is put in orange, vehicle not flyable.