The Build Part 1

Instructions for Hovership MHQ2 can be found here. Skip over the BASE ASSEMBLY: HARDTAIL MOUNTING

Note: You should have the Flight Controller, Receiver, ESCs, Motors, and Power Distribution PCB all wired up before beginning the Setup Wizard.

Useful notes:
EMAX MT2204 motors they are sold in pairs, one clockwise thread for props with a silver prop nut, one counter clockwise thread for props with black prop nuts. Now here is the part that got me, the CW thread shaft, is on a CCW spinning motor! Obviously this makes sense if you think about it, BUT they don't tell you that on every website, and being a newbie I messed that up so my motors are mounted backwards... So in this case the CW in the motor title refers to the threads, not the direction the motor spins.

Clockwise Threads (CCW spinning motor!)

Counter-clockwise Threads (CW spinning motor)

First I decided to set up the flight controller (openpilot CC3D). Tried to get on the openpilot wiki for the documentation, and guess what? The wiki is down because they couldn't pay the bill... Not looking good for future support on this product...

Thankfully hobbyking did a tutorial on how to set it up.

First download the openpilot ground station here be sure to downloard release 15.02.02. 15.05.02 does not support the CC3D.

Then follow along with the tutorial here

Well obviously things won't work correctly and be easy :(. The CC3D will not upgrade firmware, I keep getting a timeout error. I am using my Mac, so I'll switch to windows and see if that makes a difference. Getting frustrated already with this thing.

The board is working though, I can see data coming back. So this post actually worked to get it connected on my windows 7 laptop

"Perfect thanks.. Plug in card (No GCS) and Right click on start > Control Panel > Hardware and Sound > Devices and Printers And right click on icon copter control Should look like the attached pic) and Remove Device then unplug CC3D
Start GCS > Firmware page click "Upgrade and Erase" plug in card and wait at least 2 min then unplug card and restart GCS and when you plug in the card this time I hope that you going to see the connection and you can run the wizard. Cross fingers and a little pray :)"

Simple instructions 

• start up GCS, DO NOT HAVE CC3D board plugged in
• go to firmware tab
• hit the upgrade and erase button (it will not find the board and give you 20 seconds to plug it in)
• Plug in board before 20 seconds is up
• Board will be recognized and firmware will be upgraded

Very surprised and happy that it worked haha.

After that upgrade on the windows 7 machine, it worked as soon as I plugged it into my Mac. Another card failed on my Mac so I repeated the above procedure with it and it worked like a charm. Looks like they have a bug in their ground station software where it will not see the board when you push upgrade if it already is plugged in, but if it is not plugged in and it is waiting for you to plug it in it will work.

When you have successfully updated the firmware you will see a screen like below.

Onto the setup wizard!

Made it to the next screen before I hit another snag. Apparently the OrangeRx R615X uses CPPM not PPM output, and of course the CC3D has PPM, not CPPM as an option. It is unclear if CPPM will work with PPM, so I will have to do some more research. I chose PPM for now.

For multirotor configuration I chose Quadcopter X.

For the ESC setting this page states EMAX SimonK 12A ESC should be set up with 490Hz

Here is my generated connection diagram.

So in the above picture you want to put a CCW thread black prop nut (CW spinning motor) in position 1. Same with position 3. You want to put a CW thread silver prop nut (CCW spinning motor) in positions 2 and 4. 

Next I calibrated the sensors.

Well I need the ESCs connected for the next part so I guess I need to build up the quad now.

Jumping back to the CPPM question quick according to the hobbyking video the flight controller will be able to detect CPPM. So hopefully that is the case. At the end of a tutorial they say to use PWM, not PPM. So I used PWM and it worked so I guess PPM might work, but PWM does for sure.

Wiring from Flight Controller to Receiver. Used the following description and picture. 

"Yes, that one, first is the plug with 3wires white red and black, signal white to the top of the rx, this goes to throttle, then blue the alei,yellow to elev, green to Rudd, brown to gear and purple to aux, all these must be at the top"

for Orange R615X see wiring pic at end of post

Next I plugged the Flight Controller back into the computer using the USB cable.

Next I need to Bind my Transmitter TX to my Receiver RX. Making sure that the bind jumper is plugged in, if it is not the RX will not turn on, also the CC3D needs to be powered from battery, not from USB. When powered from USB the 5V out to the RX is disabled.

When wiring up the motors you can wire the three motor wires to the three ESC wires in any order, when you check that they are spinning in the right direction as part of the GCS setup wizard if they are spinning in the wrong direction you simply swap any two of the wires and they will spin the opposite way.

Good Website for setup wizard tutorial Part 1 Part 2

One thing that they don't go over is setting up the flight controller offset if you rotated it like I did to have access to the programming port on the side. Adjust the setting in the screen below to whatever rotation you have. 

The other setting that you have to be aware of is the flight mode setting. See this post for a description of flight modes. There is a switch on the Orange T-Six transmitter which is mapped to these three flight modes. When the switch is down it is in flight mode 1, middle flight mode 2, up flight mode 3. For a beginner you want to be in flight mode 1.

After setup (arm is set to throttle down and roll right) I tested out the TX and RX and everything worked as it should :).

To arm you have to hold right roll for a few seconds. If you have the ground station software open and connected to the CC3D it will audibly tell you that it is "ARMED"

All other settings were default.

Wiring Up

My wiring schematic

Another challenge has been figuring out how to wire everything up. First thing I learned is that the Electronic Speed Controller I have (EMAX SimonK 12A)  has a BEC. What is a BEC you ask? Check this page out. So basically it is a battery eliminator circuit, which in simple terms means that 1) it has a voltage regulator that will drop the battery voltage down to 5V and in my case supply up to 1A to the flight controller or receiver, 2) it will shut power off to the motors when the battery reaches a certain low voltage, but will continue to deliver power to the control surfaces so that you can land your model (this is only useful if you are flying a plane since cutting the power to the motors on a quad will cause it to drop out of the sky like a bat out of hell). Anyway this confirms that I can power the CC3D flight controller off of the ESC. 

I rotated my flight controller so that the usb port is facing out the left side of the quad.

I know some people say you have to cut the red wires from the other ESCs so you only power the flight controller from one ESC. Is that necessary? Well if the flight controller board doesn't do something smart then you would have four voltage sources in parallel. As anyone familiar with Kirchoffs Voltage Law knows voltage sources in parallel will violate the law that all voltages around a loop must sum to zero if the voltages are not EXACTLY the same. I'm sure that the ESC voltage regulators do not supply the same voltage, so I really should remove the other three voltage wires. See this post for more discussion on the topic.

Simulators, or How I Learned to Stop Worrying and Love to Crash

Simulators

After realizing that I've spent ~$350 on just my Quadcopter parts I was starting to get really nervous about actually flying this thing. When we started talking about racing we all were very nonchalant about the prospect of crashing. There was a lot of "dude we are going to be having some sweet crashes during the race!". At the time it sounded fine, but once I spent the money I was not as excited to "have a sweet crash".

So I started researching simulators. I used to fly RC airplanes and back then I had the Real Flight simulator. It was certainly not what I would consider "real", but hey this was 8 or 9 years ago. I hoped that the current simulators would have a bit more realism than the simulator I used way back then.

Since I have found so many helpful posts on http://blog.oscarliang.net/ I started there. Sure enough there was a great post reviewing a bunch of the top quadcopter simulators. I suggest you read it if you want to get a complete picture of what the simulators today are capable of, and how they compare to one another.

After reading through the post I decided to go with FPV FreeRider.

Why? Well, first off there is a demo ($5 for the full program). This is great because I bought the Hobby King Orange T-six transmitter, and while this does have a trainer/simulator port it need a PPM to USB converter in order to work with a simulator. I didn't want to buy a $100 simulator program just to find out I couldn't use my transmitter with it. 

I bought this Universal USB Flight Simulator FMS Cable Set to use with my transmitter. I tried it out and and of course it didn't work out of the box. The Orange T-six needs to have two of the pins be wired together in order for the transmitter to be put into simulator mode, see picture below. 

So I cut the cable that came with the USB converter and found to my surprise that only two of the pins were wired up. Crap... So in order to get it to work I soldered a small piece of metal as far down in the s-video connector between the two pins as I could. Not optimal, but hey it works for now until I can get a proper s-video cable and solder it to the usb converter cable.

Back to the simulator. FPV FreeRider has been great so far. Obviously it is not ultra realistic, but for $5 for the full program, I didn't expect it to be. It work on windows XP through 10, Mac OSX, and Linux! It is very light weight with respect to system requirements (I can run it on my 10 inch Winbook TW100 from microcenter). You can even switch the camera view to FPV, which is great since that is how I will be flying my quad. All in all I really like flying in it and I think it is an invaluable tool for someone that has never flown quads before.

How to set up the Orange T-Six for Simulator Use

So in order to get the transmitter to work with the simulator there are some settings that need adjusted. Basically if you try and use the transmitter out of the box the controls are inverted, and offset really bad i.e. the quad is always at full thrust, rolled to one side, and spinning like crazy. The settings I have will stabilize all of that, but one side of the yaw and roll will be a bit faster than the other, oh well close enough.

First lets turn off that annoying beeping every time you do something.

First hit the List Button

Scroll to TX Settings

Turn Sound Mode to OFF

Next create a simulator model on your transmitter.

Hit the List Button

Then Scroll to and select FUNC. LIST

Choose Model Sel

Select 10 Model and wait for it to download

Rename 10 Model to "SIM" by hitting LIST Button

Select MODEL NAME and change name to SIM

Next set the type to ACRO by hitting the LIST Button and then going into MODEL TYPE and selecting ACRO

Next invert all the channels that are used for controlling the quad. (LIST-REVERSE-change N to R)

Next set the travel adjustment to the following values. (LIST-SETUP LIST-FUNCTION LIST-TRAVEL ADJ.)

Next use the following values in SUB TRIM. (LIST-SETUP LIST-FUNCTION LIST-SUB TRIM)

Next change the D/R&EXPO to the following values.

Finally use the black switches next to the control sticks to move the cursors on the main screen next to the plane to the locations shown in the picture.

What did all that do? Well the manual explains it kind of well, but here is the gist. Reverse obviously inverts the controls. Travel adjustment basically moves the neutral point of the control to the left or right (up or down) of where it currently is, in other words it is an offset. Same with Sub Trim and the little black switches next to the control sticks. The D/R&Expo is a little different. Dual Rate affects the overall travel which the control is allowed to use. For example you start at 100% thrust available, if you reduce the dual rate to 80% you now get 80% of thrust when you move the stick all the way up, not 100%. Exponential on the other hand is more like padding. It can increase or decrease the sensitivity around the center of the control stick. I reduced the sensitivity so that it is a little easier to control the quad.