DJI Phantom 3 Versus Custom Built Camera Drone

Anyone reading this blog (does anyone read this blog?) would know that I have built quite a few camera drones - SK450, SK450 Deadcat, S500, S500 Hexacopter.  Most of them used commercial frames, APM or Pixhawk controller, and Gopro or similar cameras.  They all worked, some of the time, and I enjoyed building them.

But I was tempted by a very low price on a DJI refurbished Phantom 3 Standard and bought it.  What was it like getting a pre-assembled and integrated drone working?  In short, very good.

I will not do a full review but just highlight the big differences between a home built drone and the DJI.

Debugging - no debugging needed, just follow the instructions, watch a few Youtube videos, update the firmware and it was ready to fly.  Contrast that with hours and hours trying to get a DIY drone working well.

Features - The DJI has more features than my homebuilts, although I could add more.  Specifically, the DJI came out of the box with failsafes, FPV, full camera control from the ground, auto takeoff and land, as well as full OSD (on screen display).

Flying - I guess DJI has a lot of experience with people crashing their drones and complaining.  The Phantom is easier to fly and has a beginner mode to keep you safe.  The auto takeoff and land also prevent a lot of crashes.

Camera - The DJI camera is pretty good, maybe not quite as good as the Gopro Hero line, but acceptable.

Accessories - Good and bad things here.  Accessories like carrying cases, landing gear extensions, and props are readily available at reasonable prices.  DJI batteries are proprietary and expensive.

So all in all a very good experience with DJI Phantom 3 Standard for about $300 USD.  If you are more into flying and photography than building and debugging, I definitely recommend it.

Quanum Q-2D Brushless GoPro 3 Gimbal Test

Gimbal Mounted on S500 Quadcopter

Attached a 2D camera gimbal to the drone and did a quick test flight with my Gopro Hero3+ Black.

The included Gimbal mount on the S500 frame was not useable as there was only about 1-2 cm of clearance between the bottom of the gimbal and the ground and I was sure that the gimbal would be damaged in a hard landing (see previous review of the S500 frame).

The gimbal is the HobbyKing Quanum Q-2D Brushless GoPro 3 Gimbal.  I could not get it to work attaching the gimbal controls to the Pixhawk so I connected the servo cables to the FlySky i10 receiver directly.  The only adjustment was limiting the maximum throw on the transmitter for the gimbal controls to +/- 30%.  This makes the gimbal less sensitive to the movement of the rotary controls on the transmitter.

Successful indoor Test Flight is shown below:

Unsuccessful outdoor test flight (gimbal worked, quadcopter not so much) is also below:

Hobbyking S500 Frame Review

S500 Quadcopter

I am building a new quadcopter for higher quality photography using the hobbyking s500 frame, which is similar to the sk450, but slightly larger.  It is now flying and I can comment on its pros and cons.

Pro

• Slightly stiffer arms than Sk450
• Plenty of space for electronics
• Higher landing gear to allow for camera gimbal
• Adjustable mount for gimbal - can shift gimbal forward and backward 
• Integrated pcb for power distribution 
• Spare parts available
• Low cost 

Con

• Landing gear not too sturdy 
• Landing gear too low to use included adjustable mount with 2 axis gimbal, have to hard mount to pcb

Note Top of Landing Gear, too flexible, not well attached to frame

I used sunnysky 2212 motors and they are much better than the turnigy motors on the SK450 - powerful, quiet, less vibration, smaller. I was also able to use my pixhawk controller which would not interface properly to the turnigy plush ESCs when I tried it on the SK450. For the S500 build, I used low cost Spider ESCs with SimonK firmware, which worked well with the pixhawk. Carbon fiber props and the previously reviewed Flysky i10 radio rounded out the build. 

First outdoor test flight is shown below. 

Summary 

The S500 is a good frame for a camera quadcopter, but it is not recommended for a beginner builder. Modifications are needed for camera mounting, the landing gear, and perhaps for power wiring so it helps if you have some experience with building  quads. 

S500 fully assembled with Gimbal, Telemetry

Flysky i10 Review

I recently bought the Flysky i10 radio for my latest quadcopter project.  I love this RC unit.

The system, as delivered, includes the transmitter with rechargeable battery, receiver, external voltage sensor, rpm sensor, and temperature sensor along with a useful manual on CD.  The manual is actually well written and useful, unlike many Chinese radios.  Build quality seems good, no obvious cheap parts or poor assembly.

Transmitter

The transmitter has a touch screen interface, somewhat Android-like, and it is easier to use than the older text menu driven systems.  You can set up almost anything through the interface: limits, mixes, switch assignments, delays, failsafes, etc.  The transmitter itself is slim, with rubberized grips, making it easy to hold.  There are many different switches and knobs which can be attached to any channel.  This was great for the quadcopter as you could get 2, 3, or more flight modes on one switch or knob without using cumbersome control mixing.   Camera gimbal control is also easy with the two variable control knobs on the top corners of the transmitter, easily manipulated by your index fingers while your thumbs work the joysticks. Joystick feel is good.  The transmitter can also be programmed via USB, which I have not tried yet, and it also has an SD card for storage.  Telemetry data from the receiver and sensors is shown on the transmitter LCD display.

Home screen

Icons for customizing transmitter

Receiver

The ia10 receiver has 10 channel ports which work well with my Pixhawk and standard servos.  It also has an "Ibus" which can be used to output PPM (I have not figured this out yet), or take inputs from the telemetry sensors.  Ibus documentation is not great, so check back in a while and see if I can figure out how to use it for PPM and other purposes.  Range seems very good in my experience.

Receiver as installed on my Quadcopter

Testing

I installed the system on an S500 quadcopter and used a generic PPM converter to generate PPM for my Pixhawk controller.  It was relatively simple to set up the control functions, map the flight modes to a three position switch, and range check the system.  Performance during test flights and a long hot outdoor flying session was excellent.

Summary

I highly recommend this radio for quadcopters and believe it will also be an excellent choice for airplanes, traditional helicopters, and other vehicles.  The price, about $200 US, is unbeatable for the value received.

Sensors included with the System

Pixhawk Versus APM Comparison Review

This blog entry compares two flight controllers from the Ardupilot 3DR-Open-Source stream: the generic APM 2.X controller and the Pixhawk.  I am an intermediate multirotor builder and flyer, so this comparison will focus on functionality and useability, not on advanced features.  Also, this review is based on my experience with 5 different APM modules (none sourced from 3DR) in three different physical forms: standard, mini, and micro (also called mini by some) sourced from Hobbyking and generic Chinese manufacturers.  The Pixhawk is available from multiple domestic and Chinese sources and you should check the reviews to make sure you are getting one with decent build quality.  Each was used with corresponding GPS/Compass units from the same manufacturers.  I built three different quadcopters and used them with different controllers.

Feature/Characteristic	Generic APM 2.X	3DR Pixhawk	Comment
Size/Weight	Small	Larger	APM is available in 35x35x5 mm board.  Pixhawk is 81x50x16 mm
Cost	Low	Higher, about 4X	APM with GPS ~$65
Quality	Variable	Better	Inspect a generic APM after you get it for poor soldering, loose USB..
Support	Good	Good	The best support is from peers on DIYdrones and APM forums
Flight Stability	Good	Good	This is my experience with a well setup APM and Pixhawk, your experience may vary
Accuracy	Good	Better	It does depend on your GPS and its accuracy.  Pixhawk has a more powerful processor and more memory
Onboard indicators	Poor	Good	Pixhawk has multiple LEDs and tones to tell you status, APM has a few LEDs
Ease of Setup	Moderate	Moderate	More components to interconnect on Pixhawk, but well documented. Cables and connectors often an issue with APM and documentation must be found on the Internet.
Ability to fly autonomous missions	Yes	Yes
Mission Planner Ground Station Compatibility	Yes	Yes
Flight logging Capability	Good	Better	Pixhawk logs more information and has a microSD for storage. APM has limited storage of most important variables.
Upgradeability	None	Yes	APM code is now frozen to my knowledge, but Pixhawk software with improvements still being released
Debugging difficulty	Good	More difficult	APMs seem to always work, Pixhawk is more finicky about ESCs, setup, etc.

Overall, both controllers are excellent and have worked well for me.  The APM is a better fit for small quadcopters and is probably better for the beginner builder due to its simpler setup and low cost.  The Pixhawk is very good but it takes more time to set up and it is likely higher quality and performance, so it works well in larger camera quadcopters and similar expensive vehicles.

APM equipped SK450 "Dead Cat" Quadcopter

S500 Quadcopter with Pixhawk