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Posted by askman | Jul 03, 2012 @ 04:32 PM | 12,877 Views
well, I get a lot of queries about various things related to AP/AV as well as multicopter, so I decided to distill it down to this entry. In realtiy, the answer is TANSTAFL. So, that is the theme of this blog. If you are a reader of Robert Heinlein, you will recognize this term from the novel "moon is harsh mistress" It means "there aint no such thing as free lunch" and this really fits my answer. With new technology and competition, the price of things are dropping, but this rule wills still remain true in every aspect.


I will include redundancy into the reliability as well. In general, simpler the system, more reliable it is. but also, component selection can also make a difference.

Design consideration: design like Y6, Octo and x8 also has some redundancy in case of motor/esc/prop failure . So for best reliability, you want tri/quad, but you are trading off possible redundancy of other design. More motor means more weight and more things that can go wrong. Coaxial design also loses some efficiency. So in many ways, you are trading flight time and cost for reliability.

component selection: selecting a good quality motor that is large enough to handle the load is very important. don't try to save money on motors. it is not worth it. ESC wise, I prefer 30amp as minimum with N-fet design. luckily, you can get simonK flashed n-fet esc for good price, but serious guys will...Continue Reading
Posted by askman | Jun 29, 2012 @ 08:26 PM | 12,818 Views
if you've been following the thread on AG gimbals, you probably know that i am a proponent of Y and to lesser extent Quad for multicopter for AP. While I realize this put me in the minority, I find that for best flight performance in windy condition, Ys are hard to beat. to gain that benefit, you do lose bit of efficiency, but I think most of us are willing to make that trade.

Gary has been asking about the Y conversion kit for a while. he has shrimp and crab kit that he has to put together, but just never had the time, so he just wanted to convert the F550. when Bobolavega showed up with his conversion of both 450 and 550, I had to build one. I just created a simple motor mount conversion and that is all it took (you also need to take it apart and rewire it, but that is pretty easy on F550)

anyway, here is the pic and first good video from the gimbal that is on it.

Y550 test5 (3 min 32 sec)

I am still working on fine tuning it, but pretty happy with current result. To be honest, Shrimp is still better in stability due to compactness of the system and simonK flashed esc, but I am pretty happy with the result so far. but that also makes this an ideal platform to work out the improvements on.

Now, I get lot of question about gimbal controller. Currently, I test using controller built into naza, and HF gimbal controller. so, lets go over the list of available gimbal control solution.

1) DJI WMK : GPS lock...Continue Reading
Posted by askman | Jun 24, 2012 @ 09:53 PM | 14,250 Views
well, back to more prop talk. :

on my last update on april 30s, I've posted about gemfan cf mix prop failure. it happened again in AP use. so, I will put notice that it is not recommended to be used. The gemfans have also released some CF copy of graupners. biggest issue from what I've been reported has been QC issues. for how much they cost, they seem to have issues with hub being not consistent.

so, which are the best props for F450/550? or AP in general? well, Graupners are still favored by many, but I am having great result from using zinger wooden props.

Zingers have lot of pusher prop available, and 8x5 and 9x5 combo has proven to work as well or possibly even better than graupners in windy situation. graupners are still bit more efficient though. They do need to be balanced and bored for dji motors as they are 6mm standard bore. but they fly great.

now, some of the later batch of DJI motor (2212) seem to have vibration issues as well. on one F550 kit., I had 3 motors being unusable for AP. Earlier kits were fine, but not these. I've heard that DJI has since changed the motor once again. (etched instead of sticker logo with issue that graupners will not easily work without spacer now) dynamic balancing can help a motor, but I am finding that we cannot do it accurate enough for AP use. in another word, if you have to dynamically balance a motor, just replace it if you are going to use it in AP/AV. you can make it great for stick banging with dynamic balancing, but not for AP. this lead to another view in that you should always buy decent quality motors.
Posted by askman | Apr 18, 2012 @ 09:40 PM | 12,390 Views
well, I got my gemfans. they are nice blade. very well suited for DJI 450 and 550. you do need to drill out the hub. hub diameter is similiar to DJI blade, but with carbon reinforcement, the blades are much stiffer and should be stronger. I used step drill to get it close and reamed the bore hole to .3135. tight fit on the motor. they needed very little balancing, and it was ready to put on.

One thing I noticed about puttng on the new blade were that my 450 and 550 both were bouncing around more in the wind. they were no longer solid anymore.
so, I did a quick and dirty experiment to determine the cause, most obvious being the diskloading.

my 450 were at 1.5kg, and 550 were at 2.6kg. both with 8" and flew well in wind. this is about 200sq in and 300 sq in disk area. 1.39sqft and 2.08sqft leading to 38oz/sqft and 44oz/sqft. both flying very well.

with 9" blade, same weight, my disk area is now 254sqin and 382sqin. 1,76sqft and 2.65sqft which lead to disk load of 30oz/sqft, and 34oz/sqft.

while hexa was more stable, it still was not as stable as the quad with 8".

so, to prove this test out, I added weight to quad and brought it upto 1.85kg, which brought the diskload to 37oz/sqft and now it was almost as stable as before. . I've brought the f550 to 2.9kg and also repeated the test. and it was same . (about 40oz /sqft) very stable.

so, at least in windy condition, naza really...Continue Reading
Posted by askman | Apr 17, 2012 @ 03:04 PM | 10,993 Views
well, panasonic GF3 is getting a workout on my f550 with naza. It is a great camera and great value. with firmware hack, the video mode is as good as anything available. its four third size sensor only 22% smaller than nex-5n sensor, and used in many dslr.

anyway, I was testing my F550 with roll stabilization and tilt connected to the naza reg (roll servo had its own reg) and I got hit by glitches.

this basically reaffirm that you should never power the servo off regs that your multicopter depends on. lol. I did manage to land, but I was very nervous and I made record controlled descent. 8" props at 2.6kgm hexa load is still usable, but near the limit. I am waiting on the 9x45 from gemfans.

anyhow, here is the video.

GF3 test 4. tilt connected to RX. but powered by naza big mistake (1 min 38 sec)

update on 4/25/12
well: I finally tracked down this issue, and it was motor to esc connection. I swapped the esc out, and it is no longer an issue. I've tested that esc on ground, and it still works, so I am assuming connector issue.
Posted by askman | Apr 16, 2012 @ 10:39 AM | 10,793 Views
I finally got my gopro with sunex working well and fully focused. that was total pain to do. I finally used a street sign down the road to focus it in. just lot of iteration in 1080 mode to get it looking good in video . once that was done, 720 mode also looked good. I am using DJI 450 quad with 8" blade and naza. about as small as you can go and get great results in video

here is 1080 mode video
gopro 1080p.wmv (2 min 59 sec)

and here is 720 mode. testing fast panning (was 60fps down encoded to 30fps in sony vegas. no stabilization though still)

gopro 720r3 mode test using dji450 (3 min 55 sec)
...Continue Reading
Posted by askman | Apr 15, 2012 @ 10:29 AM | 11,184 Views
I've been doing lot of research into flight behavior and props on multicopter. Some just affirmed the old ideas and found some new ones.

This whole enterprise started with report of DJI 10" props breaking in air and trying to find alternative. Graupners are the best by all account and would have gotten the set, except for their current lack of availability precluded that for myself. So, I started testing props

The anecdotal evidence has always been to use light weight props, and this has always been old standby APC SF and EPP props. I've also had some hobby king 10x6 set on hand (they are very affordable) and purchased a set of 9x4.5 APC EP props. (figuring that they are similiar to graupner e props)

after testing, I find that APC EP props are not suitable for multicopter. they do work, but I could not get rid of wobble due to their weight. wobble was not big, but it existed in all condition and could not be tuned out. may be they would work better with slightly bigger motor, but not with stock DJI 920kv motor. also, I could not get 9x5 GWS 3bladed props to work well with naza. bit of wobble. could be due to balance issue as I could see at least 1 prop badly out of balance. (but again, 10x6 had at least as bad a balance on 1 prop and flew well) it is interesting, as gary had good luck with GWS and heavy loading. the motors do stay cool with gws 9x5. gary did have trouble getting rid of all vibration with gws, so not great...Continue Reading
Posted by askman | Apr 11, 2012 @ 06:41 PM | 9,349 Views
well, I am finally happy with the new Slow Stick LG. bit heavier than my original ones from 6 years ago, but lot stiffer. The new gopro adapter and new 4.4" gimbal is designed to be able to mount KK (openaero firmware) or openCC board.

the budget 4.4 gimbal is designed to use micro servo using pushrod to give tilt only control at affordable package with the LG.

it will be available in my website.
Posted by askman | Mar 27, 2012 @ 11:48 AM | 8,744 Views
Sorry for lack of updates:

We've been busy with servo issues for last couple weeks, and that has delayed our product launches. I am almost done with the new Airplane/Slow Stick setup and should have sample pic this week. new heli LG system is almost ready for testing as well. (I am trying to make a sample this week as well) lot of work going on as we push for product release of multicopter gimbals. Should update my website this week as well with some products being offered.

For airplane, we are testing KK board to stabilize the plane instead of stabilizing the gimbal. I believe this may be a good option for many. KK board combined with happysunday's openaero firmware looks to work really well. I will be using nano version of the code with older HK-kk board and full version with my blackboard. I will also test openCC board with gimbal control later on as well using tilt only stabilization and dual stabilization using 2 axis belt driven airplane gimbals.

Heli LG system will use proven multicopter gimbals. it will be offered with nex5 sized gimbal for 50 sized and DSLR gimbal for 90sized. tilt only will have adjustable roll angle to give you lvl video while hovering. 50sized should be available in 2-3 weeks while 90size is still 1 month out. with gimbals already being tested, just the LG unit needs to be tested for strength and manufacturability.
Posted by askman | Feb 28, 2012 @ 11:43 PM | 8,416 Views
well, I finally setup a new website. mostly information only at the moment, but will be adding to it. check it out and let me know what you think.
Posted by askman | Feb 17, 2012 @ 11:24 AM | 8,147 Views
Current Product roadmap 2-17-2012

Gopro vibration isolation mounting system. (samples going out monday to tester)

F450 quad system: (nose mount)
Gopro 2 Axis gimbal
Gopro Tilt Only Gimbal (upgradeable with roll)

F550 Modular system:

F550LG system
GoPro Tilt only vertical gimbal
GoPro 2Axis gimbal (complete with roll)
GoPro 2axis Yoke with roll shaft /front plate
nex5 Tilt only vertical gimbal
nex5 2 axis gimbal (complete with roll)
DSLR TIlt only vertical gimbal (design complete, available soon for testing)
GoPro 2axis Yoke with roll shaft/front plate
Pan Module for the LG system (design complete, sample going to tester)
Roll module upgrade for the Vertial tilt only gimbal.
various part kits for LG and gimbals.

Version of gimbals for mounting to AGLhobby Frameset/floating mount. (available soon)

Polecam module/adapter for all the gimbals. (including tilt only and roll/tilt gimbal) (design complete)

coming soon:
DSLR 2/3 axis system. (being designed)
Posted by askman | Feb 11, 2012 @ 11:08 PM | 7,558 Views
as promised, I will release some of my old gcode file used to create some of my old camera mount. I am starting with the old APCAM seris for slow stick. It is released under GNU GPL for personal use only. not for commercial sale. I am also making available the SS LG file.

I will update this thread as time permits. I code most of mine straight into gcode instead of using DXF. so, check back regularly for complete set.

next is trex 450 LG setup (v1.2) which uses the apcam gimbal.

I used old eco 8 ball and ball link on the apcam gimbal, but just about any ball link can be used. I also used 1" diameter delrin with 1/2" hole to make the ball link joint.
Posted by askman | Feb 01, 2012 @ 10:17 PM | 7,630 Views
as I have announced, I am back in business, but I will not be selling directly. My good friends at tppacks and dji-usa will be handling all my products for now. This is so that I can concentrate on developing my product line and produce best camera gimbal at affordable prices.

I have many ideas I want to working on, and as they become close to final product, I will have some beta testing opportunties for some people on new products. I will announce such opportunities here.

First items will be available for sale by 10th of Feb. These will include:

Gopro Gimbal in either Nose mount configuration or for DJI550 LG system.

DJI 550 LG system base kit.

latest video from seismicwave on HFP

20120202 askman "Crab" and gimbal test NEX 5N HFP (2 min 33 sec)

he is also getting the latest LG system and parts to update his gimbals. he should have it by saturday. I also expect Gary to have his DJI-550 running. I will also be shipping couple test unit early next week as well.

I am trying to get enough testing on various platform before release, so we can have successful launch. If all go according to plan, nex5 gimbal should be available by second half of the month. I will also have Polecam adapter and Pan adapter should be available by this time..

My next project is the DSLR version of the gimbal which will have a deeper and wider yoke I believe this will require slightly heavier duty LG and roll assembly. I will need to test it thoroughly before I will be confident. target is 3lb camera load. (most DSLR with reasonable lens)

the 550 LG system can easily be adapted to other multicopters

Nex5 system is in final testing, and will be available. (this month) It is very simple to change from gopro to nex5 so if you prefer, you can also get it with both yoke.

anyway, glad to be back.
Posted by askman | Jan 30, 2012 @ 11:17 AM | 7,008 Views
with help of seismic, I am learning lot about various FCB and its foibles. Gary has been having pretty good result from Naza at least flying f450 and my gopro gimbal. I also have gotten some hoverfly Pro footage from Seismic using my nex5 gimbal on my crab folder testbed. (thanks seismic)

20120129 askman crab HFPro NEX 5N (2 min 14 sec)

there are few things we need to do on servo setup that should improve things, but not bad for early test. we've been having some issues with openCC board with the gimbal control, so I will be looking at this issue this week. Seems like the state of gimbal control is bit of gamble. on the open sourced firmware, we will be giving feedback to the coders to see if they can make firmware fixes. I do believe as a community, we need to do our best to help out, but it also tells me that we need an affordable camera control board that we can setup specifically just for camera.

I will post more videos as I get more. Gary has been busy getting F450 setup perfected, and his latest videos are very encouraging. so pretty happy with how the gimbal is performing. I am making some minor changes for easier manufacturing and reliability, but overal, it is all set to go.

here is latest f450 video. Gary is running 5v on his servo, and going to try 7.4v next.

F450 GoPro Gimbal Test-08.mp4 (4 min 41 sec)
...Continue Reading
Posted by askman | Jan 14, 2012 @ 10:25 PM | 6,959 Views
Since cat is out of the bag so to speak, I am back in to developing new product for Aerial Photo. First of them will be tested by gary goodrum and seismicwave. gary has the gopro version for his DJI being setup and seismic will soon have his nex5 version designed for the new folding quad that I posted here. I am working on the new leg system for the two gimbal, then I will add pan system as well. I will also be updating the Large DSLR gimbal, but still deciding on the roll. to keep it affordable, I may go top roll with belt drive, but yoke design is still in the running.

I am also updating the pole cam gimbals. The updated design will be for smaller DSLR that is so common these days, and premium put on lighter weight and affordability. There are good heavy duty pole cam gimbals available from other vendors, but nothing that is lighter for average AP professional that want to use the latest camera that offers excellent performance without the weight. I will have 2 and 3 axis version of polecam with open loop servo.

anyway, I will post more detail/pic as I get them finished.
current status : nex5/gopro nose and underleg mount system is almost out of design and being testted. will be available very soon.

I am making it so that it will be very easy to change between the gimbal from leg to nose setup. (need 2 piece adapter kit costing 10 bucks)
LG system will be very rigid and strong. it is 17 CNC'd part and will have some flexibility to mounting the gimbal.

Nex5 gimbal is designed to use the pancake lens. recommended total load of 1.5lb/600gm or under. The yoke depth will preclude usage of large/heavy lens. If you really want to fly the heaviest lens, you will need to get the DSLR version which will have deeper yoke and designed for heavier load.
Posted by askman | Dec 10, 2011 @ 11:10 PM | 7,397 Views
well. 10mm version is fairly on its way, and I wanted to start a 5/8" boom version. so here it is start of the build. main plate with mount for battery/gimbal. it will use .25" fiberglass tube for the gimbal/main. I have do some work to make sure it works and is safely secured. I have some ideas to add extra security. tomorrow, I need to pick up some tube and make the battery mount and the gimbal. I will also need to mount the boom and motorplate/lg setup. with 15" boom (half the bar) you will end up with quad that is 20"x30" motor to motor. this will be setup for 12" blade and 4S5000 pack.

current weight is about 16oz. it is really heavy duty as I made it with 3/32" thick g-10. 3" long LG should give plenty of clearance for the nose mount camera gimbal. (and easy to make it longer) I can easily shave some weight. anyway, camera gimbals are next.
Posted by askman | Nov 25, 2011 @ 04:57 PM | 5,995 Views
well, I've decided that I want to concentrate on smaller folding quads/y6.(upto 2kg auw) I have a proto quadcopter flying with rectangular geometry and it flies like a dream with KK board. will be testing a folder out with uavx. I also have y6 built with kk, but it is bit harder to fly and orient. put it down hard due to loss of orientation. have to replace a shaft or two.

anyway, got the first frame cut. I want to build a pair of them. one with KK and the other with UAVX/roll/tilt stabilization.
Posted by askman | Nov 22, 2011 @ 12:57 PM | 6,109 Views
been working with UAVX and now I am prett happy with how it flies. (thanks Greg aka gke for the latest firmware) I will continue to work on this as my base platform. I really think UAVX could be a great setup with new ARM processor board and 10DOF from drotek or one from canada (can't remember the name, but was selling for 75 bucks) MBED being 60 plus some form of shield requirement makes it bit tough. really need ready to go board that cost about under 50 bucks without needing extra board (similiar to seeeduino mega) current UAVX at 40mhz is usable and decent board, but getting old.

anyway, spent some time compiling the list of available fcb with features, as my desired features are : acc/gyro, good alt hold and camera stab. no real desire for GPS/Mag sensor as all my flying will be relatively close. (and from what I've seen, GPS is still not really reliable on most units)

AD-50q: (foxtech) acc/gyro+ camera stab about 160 USD. just came out. no real field result available. closed firmware

multiwii/miniwii: 70 euro for miniwii. acc/gyro optional compass/baro (bma085baro cost 20 bucks) camera stab plus trigger available. v1.9 has decent alt hold. arduino/atmel based. open firmware

opencc: ARM based 90USD acc/gyro. + early camera stab . open source firmware. no baro.

afrocntl: acc/gyro/baro. no camera stab. 10000 yen (about 130USD) C based code. requires PPM RX. I2C esc or I2C to PWM...Continue Reading
Posted by askman | Nov 09, 2011 @ 12:56 AM | 5,908 Views
been flying HK-KK setup for a while now and been really happy with v4.7. so, I started to build my new AP rig.

I really need to build a good camera mount for this use, but I have adapted what I have, which will be good enough for taking stills and hopefully fixed video. it is bit flimsy for my taste. still, it will get me going and allow me to test the new frame.

so far, weight is at 480 gm with FCB and some wires. motor esc should add about 450gm. so lets call it even 1kg plus batter and camera. 1.5-1.7kg auw. so far so good.

I will need to design a new camera gimbal. probably with belt driven tilt for this one. I may add belt driven roll as well if I am willing to add bit more weight. we will see. once design is proven, I will cut it out of CF for that added rigidity.
Posted by askman | Nov 01, 2011 @ 03:34 PM | 5,649 Views
after running AskmanAP for 5 years, working 2 jobs without time off took its toll on my health and marriage. I was facing high blood pressure, chronic fatigue as well as nasty gastro intenstinal disease as I gained lot of weight during this time. The final straw was issues I was facing with my family life, and I had to stop the ever speeding wheel I was on.

I really want to issue a formal apologies to all the customers that supported me during the years. My life was so bad, I had to walk away from the business to salvage the rest of my life.

fast forward 3 years.

I am back down to healthy weight (and looking to get down to 10% body fat), my family life is back on solid footing and I am healthy again. I am slowly getting back my interest in the RC - multi rotor, but really no desire to go back into the business. I will be posting all my old G-code used to cut the mount and put it into public domain. Sorry I don't have any DXFs as I designed them all in my head and hand programmed into Gcode.

It is good to be back. and I beg forgiveness of everyone and thank those who cared abut me.