Markus

Markus – First custom drone I've made (ZMR 250) (Built in early 2016)

  MarKus is a 250 size custom built drone using then popular ZMR clone frame back in 2015 when I was serving in the Airforce. I was marveled by the movie Gladiator and just had to name my first drone after a vicious Roman name. It was supposed to be Marcus but I changed “c” to “K” because I thought it would look cooler that way.

Goals for the build was to:

• make it as cheap & light as possible
• fly FPV

Parts I used for the build are:

Frame: ZMR 250 glass fiber 250mm

Flight controller: Naze32 6DOF
PDB: Hobby King Quadcopter pdb lite
Motor: Emax 2204 2300KV *4
ESC: Simonk 12A *4
Receiver: V8FR-II
Propeller: Gemfan 5030 2-blade
Battery: Zippy 3cell 2200mah 25C

Pre-assembled - This is what it should look like with the original frame design

The top section of the frame along with the aluminum standoffs were removed for weight reduction. 

Wires are relatively cleaned up.

Camera attached for FPV flights. It is attached to the 9g servo for camera angle adjustment in 3 positions. 

I didn’t have on screen display features back then so here is a ghetto way of checking voltage in mid-flight: just attach a voltage checker on the quad.

  I built this quad while I was serving in Airforce at Kunsan. With my hourly wages of about 30 cents (that’s a normal wage for soldiers serving military in South Korea for mandatory citizenship service), I had to compromise with the amount of budget I spend on the build. At the end, I got a flying quad with crappy flight characteristics. The quad was already overweight (approx. 380g w/o battery) and was flying with 3cell 2200mah lipo battery which was no good. Even with the large battery, the flight time was only about 10 minutes hovering. The PID adjustments were inconsistent (this is probably my fault) so the quad liked to oscillate even from small movements or external forces.

For improvements,

• reduce weight
• use lighter (less capacity but higher voltage) battery
• better electronics (motor, escs, flight controller)
• shorten the excessive wires (battery wires were dangerously exposed to propellers)
• use proper fpv goggles (I tried to save money and used my galaxy s4 as a screen. Latency was at its greatest)
• replace dipole antennas with clover leaf antennas
• use more “punchy” props
• install proper OSD 

  There are more improvements I could think of but that seems like the most important things that could affect the performance at the given state above. Anyway, building this drone was a good practice for a starter like me and will be helpful in future upgrades/ new builds.