Hobbyking KK 2.1.5 flight controller

The Hobbyking KK 2.1.5 flight controller

You might like to take a look at my build with the KK2.1.5 here
Turnigy Talon Carbon Fiber Quadcopter Frame build

If you are looking for a serious contender to the KK2, you might want to check this article her
CC3D flight controller

Well i will be the first to admit that when  i originally weighed my flight controller purchase options I neglected to look at the KK 2.1.5. My buddy recommended it to me saying it was quite a good controller, but I was looking for GPS, bluetooth, telemetry and plus all the options that megapirates flashed board has to offer and yes i was probably way off due to the fact that this was my first quad build, but don´t get me wrong it has been a fun process learning about how quads work , configuring Bluetooth and getting the GPS to connect, smoking a thing or two,  i would do it again, but if you looking for flight time, easy installation, simple no fuck around controller the KK 2.1.5 is for you.

 Firstly the price is very attractive 24 bucks off Hobbyking, compared to 70 bucks for a Crius or MultiWii pro, the board comes in a foam casing that you can use to mount the controller with on your multi-rotor to protect it from water and light knocks. I believe that you can for a few bucks more purchase a hard case version.

Secondly there are roughly eight or nine wires that you need to get connected and then you are off, all configuration is done on-board the controller using the LCD screen and this is specially handy to making small adjustments to your multi-rotor between flights.

The board has a built-in voltage sensor, once configured the flight controller monitors the battery voltage and gives you a series of warnings  when the battery is close to running out of juice.

The flight characteristics of this board are fantastic, the first flight went well with no adjustments made to the settings, it was simple control and very stabil in flight, it had a slight oscillation, but that could be taken care of by simply dropping the quad and adjusting using the LCD screen and then testing again, much faster that the Crius or MultiWii pro that often require a laptop or telefon.

This board comes with a stabilization or auto-leveling, this can be activated by either flicking an auxillery switch on the radio or using the stick control. Which ever method you choose requires a simple in the menu activation. Auto-level works very nicely on this board, Even though i gradually am learning to navigate a multi-rotor, i still crash with the Crius/MultiWii due to wrong PID settings and so one. They have and still do give me problems setting up. With the K.K i was able to drain several  batteries with out a single crash. You can download newer firmware and a well made manual from this guy http://www.rcgroups.com/forums/member.php?u=367321

Bottom line, i will stick with this board for a while and become more experienced with the sticks, in the mean time I can play around with the telemetry/FTV and all the other fun stuff on my new build. If you are looking for a good simple board that will start you up quick, give you success on your maiden flights and help you gain experience then this is a clear choice compared to the more expensive board that require more additional knowledge...Happy flying

Hobbyking H4 Quadcopter motor mount repair

Just a quick tip on the fixing the weak motor mounts on the Hobbyking H4 quadcopter, i mentioned it in an earlier article, but thought that i would dedicate a small article on this matter.

I purchased a set of aluminium mounts off ebay at hobbycnc for £9 + shipping, he has the original H4 equivelent in alu, but at the time of ordering, his stock was depleted so i opted for another design, this required that i re-drill the mounting holes on the tube.

The package comes with 16 screws for mounting the motors.

I weighed the original mounts as i thought the alu version would be much heavier.

It turns out to weigh exactly the same 10 grams.

I weighed the mounts for the Hobbyking X60F, which were currently mounted on the quad, they weighed in at 33 grams, so a bit of weight saving can be done here.

Mounting required drilling a new hole through the arm.

Simple.

Mounting the motor was pretty easy compared to the original H4 mounts, the motor aligns nicely and the screws are easily mounted.

Bought some replacement square tubes off ebay, for $8 http://www.ebay.com/itm/300774845368?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649 for future needs, in case of bent or broken arms.

Have now had these motor mounts on my quad for about 1 year, they are solid and almost unbreakable, they bent under heavy crashes, but can quickly be straightened with a rubber hammer. They can take a lot of strain from bending and straightning without structure breaching. This is a five star upgrade to your quad.

Why not to throw away broken things!

Well novices like myself, will often run into broken propellers,  motor mounts, motor arms and so on. Getting replacement parts takes time getting and costs money, as an example just ordered the H4 quad and after 3 flights the motor arm and motor mount broke...so another break from quad fun....no, get your broken stuff and DIY. The previous frame i was using the, Hobbyking X650F Glass Fiber Quadcopter Frame had a broken motor mount so i striped the whole unit and grabbed two motor mounts and arms, i was able to mount them on the H4 despite the fact that the width of the H4 tube is 0,8 mm and the X650F is 13mm. Not sure if the frame will hold but it is worth the try. I didn´t have a drill to drill new holes to mount the front two arms in a H form, so i used the two holes in the front of the frame. Not sure whether this construction will work, will have to just try, if not then i just re-drill the holes and go back to the original design.

Hobbyking H4 Quadcopter frame

Hobbyking H4 Copter Multi-Rotor Quadcopter Frame 470mm

You can also check this article Hobbyking H4 Quadcopter frame remodelled
You can also check this article Hobbyking H4 Tuning for better flight and video

Well after a number of crashes the carbon frame on the Hobbyking X650F Glass Fiber Quadcopter Frame, could only take so much of a beating, bits and pieces are now falling off, even after minor crashes. So i decided to purchase a new frame.

The Hobbyking H4 Multi-Rotor Quadcopter Frame is relatively fair priced, $29 + shipping, i was to choose between a cheap ebay multirotor quad frame or the H4, the choice fell on the H4 as i has tubes to get rid of the wiring.

The package comes neatly packed, with the bits and pieces bagged in sealed plastic bags. There is no boxed manual but it can be downloaded off the Hobbyking website and the H4 is pretty simple to construct.

 Note if you going to hide your wiring, construct the frame leaving either the top or the bottom frame  unmounted until your wiring is done and tested, it takes quite a while to get all the nuts undone if things go wrong.

Other things to be aware of on this frame, the flight controller mounting holes on the top plate, are partially covered under the parallel green tubes, this is a slight drawback, screws can be mounted by lifting the tube, but when tightening the whole frame, you will notice a slight uneven crest on the carbon plate, after mounting the whole frame and tightening the screws. So live with it or re-engineer it.

 

You have to find/buy a special small tool to mount the nut through the motor mount hole, I simply reversed the nut and bolt, so the bolt goes through the bottom, put the bolt and balanced it on an Allan key and then fed it gently through. The nut was tightened from the top, not very neat, but it did work.

The Landing gear is the biggest con on this unit, during flight even smaller rough landings, causes the landing gear to bend or flatten. They can be put back in place relatively easy, but at the cost of wearing the metal out. This is where I see my first breakdown, unless i engineer some way of strengthening it.

 The tubing is pretty tight, so feeding cables through them takes some patience and some relatively stiff wire.

I could not align the holes to mount the motor the way i wanted so i could run the cabling from the as in the picture. I can only fit 3 of the 4 screws, making it vunerable when crashing. I might have to r-drill the last hole.According to some users the motor mounts are susceptible to breaking when hitting the ground, even at low speeds.

Things got messy with all the wiring, but all the more fun to build

Power distribution mounted

Flight controller - With the cabling in place, I had to remove the upper middle plate, the cabling is too high, because of having the power distribution board

Notice the red and black cable to the Power disribution. They are over the edge of the frame, doe not look good, will have to think of how to take care of that.

As a novice, one of the great things about this frame is once the quad is airborne, its stability outclasses the X650F, keeping the quad in the air was much simpler and leveling was achieved almost from the first flight. Due to the reduced weight of the frame compared to the X650F, this frame archieved longer flight times, so to break it down, cool frame, stabil, good for longer flight time, but very easily damaged compared to the X650F, Much of the energy in crashes on the X650 is absorbed in the flexible landing gear, and also the tubes connecting the motor arms to the frame will also give as the outside bolt is designed so that the arm will give, when an arm hits an object, causing it to absorb the energy from a crash. The X650F can take a bit of a beating, before something breaks. The H4 does not have this play, an unfortunate crash on the motor tube will break it.

Be aware that Hobbyking does not seem to stock spare parts for the H4 frame as of yet, a look at the International warehouses website, shows that spare parts for this frame are not available so if something breaks, well either a new frame or get busy engineering.

Took the quad for a flight, while banking at a relatively slow speed, the one motor seem to cut out, dropping the quad from a height of 3-4 meters. It broke the motor mount, so have to re-engineer the prop mount.

Also broke the aluminium tubing, so as mentioned previously this frame is easily damaged/broken

Bent tube.

I decided to strengthen the frame by mounting the old motor mount tubes, this helped in making the quad withstand a bit more. The X650 which i used earlier has stronger tubes and thicker motr mounts. The tubes here are angled because my drill was out of action so just mounted them angled until i found a drill to mount the tubes at a right angle.

 I removed the original landing gear and mounted the landing gear from the X650F, i did it by simply drilling 8 x 3mm holes in the bottom plate for the landing skid mounts, making sure that the holes did not collide with the exsisting holes for tightening the bottom plate. There is a small bulge in the bottom plate, where the screws are tightened. That i can live with.

The mountd Landing gear seen from the bottom

The landing gear has given me enough clearance to mount my gimbal.

The Gimbal was mounted with three screws on to the bottom plate, making sure that i kept the holes for the motor mounts free.

If you are looking for reinforced motor mounts  for the original motor mount arms, you can order these aluminium mounts from Hobbycncoff ebay. The direct link follows below the picture.

http://www.ebay.com/itm/H-Copter-H4-QuadCopter-Multicopter-Aluminum-Motor-Mount-HobbyKing-4-/301643548846?pt=LH_DefaultDomain_3&hash=item463b5b48ae

SimonK firmware

I heard quite a bit about the SimonK firmware and thought i would try to fiddle around with it and  try to get the firmware programmed on my Turnigy Multistar 20A ESC´s. The SimonK firmware apparently give you a smoother flight, a more responsive quad by changing the timing provided by the ESC. It also removes features that work well for planes, but are not good for multirotors, like the low voltage cut off, saving your battery. This procedure is specific to my hardware setup, not all ESC´s have the ATMEL chip, so be sure to check out this site https://docs.google.com/spreadsheet/ccc?key=0AhR02IDNb7_MdEhfVjk3MkRHVzhKdjU1YzdBQkZZRlE#gid=0 to check your configuration. All that i have done is of coarse your own responsibility if you do decide to try it, things can go wrong and you might end up buggering your ESC.

You can off Hobbykings site purchase several preprogrammed ESC´s pre flashed with the SimonK firmware like the Afro ESC series saving you the hassle of what I am doing, but I love to do it the hard way. So I purchased a USBasp programmer for 3 dollars off Ebay. 

The USB ISP programmer

The USBasp comes with a 10-pin connection cable, so i needed to create a tool to do the flashing. You can purchase a Atmel Atmega socket firmware flashing tool from Hobbyking at quite a steep price, $19, this does the job pretty quickly and does it by simply placing the tool on the MCU socket and flashing, but i prefer to save the 19 bucks, so I set out to build a tool to take care of the job.

I grabbed two, JR servo extensions leads with three wires and some header pins and a broken ESC for testing purposes.

I then broke off two rows of the header pin, keeping the plastic intact to keep the pins stable and straight.

I inserted the header pins into the JR servo leads with the long edge inserted first

 

I placed the two JR servo leads adjacently and taped them together, I was careful not to cover the wiring as I needed to follow the wire when connecting it to the asp unit

I cut the ten-pin cable and split the cable as shown above, striped the ends so I could solder the JR servo leads to the 10-pin cable.

 I found this diagram on the internet and used it to solder the cable correctly.

The Cables have to paired together and soldered, remember the correct direction as one can easily get confused and end up swapping the direction when flashing, I used a piece of tape to help me remember left from right.

Once done the cable looked like this and ready for flashing. I downloaded the flash tool and the driver for the USBasp http://lazyzero.de/en/modellbau/kkmulticopterflashtool. I installed the software and the driver, fired up the software. 

My software settings were as above.

Prior to flashing my quad ESC´s I took my broken ESC striped off the heat shrink and ran a flash test with the new cable to see if things went as planned. The USBasp provides power via the VCC cable so keep the 5volt jumper shorted on the asp

On my quad I cut out  a small section of the heat shrink, that was equivalent to the ESC that I had stripped, took off my props and simply did the same flash procedure. After flashing I simply taped the hole that I used for flashing.

A quick Ebay tip

The X650F comes with a stack of M3 plastic screws, Nylon Hex Spacers, stainless steel hex screws. The Hex spacers tend to wear and the threads become useless, this will in time require changing the screws. Around the motor mounts some of the stainless steel screws tend to fall out, making the motors vibrate more, this problem can be as mentioned in a previous article eliminated by using loctite on all the screws prior to mounting them. Hobbyking has most of these spare parts but at an expense. 10 plastic screws at $9 dollars is quite steep and on top of that you have to deal with $3-4 dollar postage rate. I searched Ebay for nylon hex spacers and here, there were bucks to be saved a whole box of assorted hex spacers and screws for the sole price of $8,89 including postage seemed like a good bargain, there should be enough parts in this box for replacements on this model and future models for a while. The only drawback is the three week delivery time.....

 This set will cost you you $8,89 including postage

This set is a bit more expensive $11,98 was the total charge.

This set like the above cost $11,98