The title of this post alludes to the pod races that are portrayed in Star Wars Episode 1.
Carnage, death and destruction abounds in this bloodthirsty sport. Parts fly, egos clash and only one is victorious at the end of it all. And yes, I am referring to Quad racing, not Pod racing.
Quadcopters have taken off (pun intended) and are quickly becoming the preferred means of entering into the RC hobby. They can take off and land vertically, are highly maneuverable and can be used to get pretty epic visuals from high vantage points. They are literally popping up everywhere, and nearly everyday there are reports of drones doing something they aren’t supposed to and making a break for freedom (DJI Phantom owners, you know who you are).
But those are the boring..er aspects of quads. A new breed of quadcopter is the 250 class racer. The 250 in the name refers to the motor-to-motor distance in mm. Hence a 250 quad has a motor-to-motor distance of 250 mm. These feature smaller propellers than their larger counterparts (5-6 inch compared to 9-10 inches), higher kV motors and are built for all out speed and maneuverability rather than endurance and load carrying capacity. Flight times range between 4-8 mins per charge, which is expected considering the rate at which they haul ass. These weigh about 400-600 gms fully loaded.
(The following pics are from a Sunday Fun Fly day we had at GeorgiaTech, more pics here: http://ufc.gtorg.gatech.edu/?q=photo-gallery)
But the type of quadcopter is only one aspect of this fledgling ‘sport’, if you can call it that, that makes it so interesting. Quads themselves have existed, in one form or another for about 10 years. The advent of better motors, battery technology and flight controllers which can handle independent motor control and perform complex 3D calculations in quaternions have enabled the development of faster, cheaper and lighter machines. The turning point came in the form of First Person View (FPV) systems.
FPV allows the pilot to fly the aircraft from the point of view of the aircraft itself. It puts you in the pilots seat without all the safety and costs involved in actually flying a full size aircraft. With all the insane flips and rolls they are capable of, you wouldn’t want to be in it without a barf bag. An example of what they are capable of:
An FPV system consists of a camera, a transmitter on the quad, a receiver and a viewing device. This can either be a screen or goggles (both shown above). People also attach secondary cameras to record their exploits in high definition.
This post was a long time in the making cause I wanted to finish it after I finished making my own 250 monster. And finally, here it is :
It’s a ZMR 250 clone frame with Emax 2204 motors, 12A ESCs, 5030 props and a CC3D flight controller. I’m using the El-cheapo Quanum FPV goggle set from Hobbyking. I haven’t actually flown FPV with it yet cause, being a noob, I definitely need a spotter as it drifts around a lot while flying. While flying FPV, the only direction you can move is forward (atleast when you’re starting out) as the camera has a narrow field of view which only points in the forward direction. Movement in any other direction doesn’t actually register in your head and you find yourself drifting all over the place. Pretty soon, you’ll find yourself casually drifting into a tree (incidentally, trees are the number two cause of quadcopter crashes, only second to Phantom flyaways……… I think).
Currently, I’m running a 1500 mAh 3S 35C LiPo battery. The number 3 indicates the number of cells in series which compose the battery. The 35C gives how much current the battery can supply, i.e. 35 X capacity of the battery. So this battery can provide 52.5 A at peak load. Considering that the burst current of the ESCs are 15A, I dare not push the motors as the peak current will be 60 A burst. Even with half throttle, this quad is a beast for my current skill level so I’m not complaining. It’s plenty agile even when the CC3D is in Horizon mode. The few times that I’ve flown in Acro mode, it spiraled into the ground even for slight touches of the stick so I’m not trying that for some time, until my reflexes improve.
The pros have varying setups but they’re generally high powered: 20A – 30A ESCs, 70C batteries, Naze32 boards (which are supposedly better than a CC3D at high speed) and 6045 props. Batteries range upto 6S which gives them insane power to weight ratios of around 4:1 in some cases. For what those are capable of, look below:
Well, this was long post. Will update when I get a video of me flying 😛
Until then, to infinity and beyond!