Hey Guys! The Big question is exactly as the title says, Which do you prefer for your CS8. Would like to hear from those who have either or both. Pros/Cons ect.. just overall review of each product right from the source of its users. Getting ready to purchase my CS8 w/ 3 axis gimbal and would love to hear everyone's opinions. (will be flying Cannon t3i) Thanks for any and all help you can give!
My Cinestar Octo will be carrying the new DJI A2 which is an improvement over the DJI WKM. In addition to many more free channels, there is a built-in s.bus receivers that is 100% Futaba compatible and generally compatible with many other RC radio systems. My previous experience with the WKM has been excellent as well with over 150 successful flights..... however the WKM is renowned to be overly sensitive to MR vibration.... apparently not an issue with the new A2.
Well for what its worth...... here is the new DJI A2 mounted on my Cinestar 8. The mounting plate is 1/32 in aircraft grade plywood sandwiched between two layers of carbon fiber - epoxy matrix. The Hungry board PDB sits underneath.... ESCs will be mounted underneath the A2 mounting plate soon.
I have both, although putting together the WKM at the the moment however I have about 10 flights with a WKM sysytem, enough sample to make assessment. MK PROS: 1. It is the avionics that the CS8 was originally designed for, no need to fab your own mounting parts. 2. Has more options in firmware to tweak the system parameters and fine tune. 3. The availible Smart OSD has more real time telemetry being down linked, for system performance. 4. It has on board data logger, to investigate anomalies 5. Has a fairly good reliability record 6. The head of MK seems to take issues that get discovered serious to try to fix firmware glitches, MK has a better buisness ethic than DJI at the moment 7. Supports up to 12 motor systems MK CONS: 1. Exposed circuit boards more susceptible to environmental issues 2. Takes a little longer to learn the functions of the firmware, no actual manual just a wiki site available where the info seems piece milled 3. Until now it was only setup for 4S batteries without hacking the board with a soldering iron and using after market dongle to mate to non proprietary ESC's. 4. 4S setup IMO is not ideal for this size of rig. I feel that the 4S cinestar is severely under powered for flight safety margins, the fix is an I2C converter to put on aftermarket ESC's, although you now have an additional critical component that whole system is riding on. 5. Native MK ESC's require you to have descent soldering skills unless you buy RTF unit. 6. Native ECS get hot real quick, although there is a work around by adding a fan to them. WKM PROS: 1. plug and play the only soldering that is required is to replace the XP60 battery connectors with more robust ones. 2. After market ESC's can be used without modding 3. Has a full product manual online 4. Now has data logging available, it is achieved through an on screen display device that you have to buy separately, but you should one these to look at real time parameters 6. Set up for 6S without any mods 7. Electronics are enclosed so failures due to environmental's, such as moisture are less likely WKM CONS: 1. Not as many user tweakable options 2. GPS and magnetometer seem more susceptible to magnetic influence. 3. The IMU seems to be more susceptible to mechanical harmonics 4. DJI seems to have a bad track of releasing new firmware that has catastrophic errors, in general it appears DJI is using the end user a beta without their knowledge 5. The DJI On Screen Display is not as good as the third party Smart OSD for MK 6. DJI customer service is lacking they appear not to acknowledge peoples issues with their systems. 7. DJI seems to have a bad reputation now for releasing products that are not vetted properly leaving the customer to be the gineua pig. That's it in a nutshell. DJI can be safe and reliable as long as your not the first in line to buy new hardware or upgrade firmware. I bought WKM over the A2 becuase of some issues with A2 for the RC tansmitter that I am using. DJI A2 is setup to use Futaba controllers in their A2 with support for others, but the others have not been figured out yet. Shaun
You are so PC Customer service 'lacking'? Steve, I fell out of my chair laughing. I am waiting for the day when anyone on any forum announces that they had any type of discussion with DJI tech support, either via email, phone, telepathically, flares in the sky, semaphore or smoke signals. Second thought forget the smoke signals, to many of those from go home to China. At least you CAN get a direct answer from the Holger. Might take awhile but at least he does post.
Shaun..... The Cinestar products were originally developed for the MK, one of the earliest quality systems, and most on this forum are using MK..... Few can afford the time and money to work with both.... your posting is useful pro/con summary data........for the most part. In my case I started out with DJI WKM but wanted a better MR airframe which is why I am on this forum now. Configuring and bench testing the A2 on my Cinestar 8 right now..... I am expecting it all to work out well and will update results here regardless.
Shaun I think you can make the same argument with MK 2.0 for #7 right now. Also out of curiosity why do you feel the GPS is more susceptible?
For the sake of being a bit more precise....please except my apologies if this is too intense but I am an Enginerd and get quite a kick out of the technical details!!! The "GPS module is a combo GPS receiver c/w digital compass and some additional smarts (fw upgradeable etc.) It is the digital compass that senses magnetic fields and the more sensitive, the better. The new DJI A2 uses a much larger GPS compass PRO which is proving to be much more accurate although there were apparently a few defective ones released. The magnetometers are built in to the IMU along with the barometric sensors and accelerometers etc. It has been claimed that the IMU on the NAZAs and WKMs are overly sensitive to mechanical vibration. Harmonics, i.e., multiples of the resonant frequency of the airframe or motors etc. have less amplitude but may also have an impact. In any case the A2 design resolved those issues to a great extent. I have to agree with item 7 although DJI seems to be taking constructive criticism seriously and making necessary changes.
You have point there about Mk 2.0 it does seem that it was not ready for prime time. Although to echo Gary , Holger does seem to acknowledge when the system has errors, even catastrophic safety issues. 0.88 firmware the copter would go into failsafe on the ground if the motors where still spinning and Rc signal is lost, for example. When Holger was made aware of this he immediately put out a safety bulletin on the MK website and released the fix soon after. To clarify number 2. In addition to Graydon's info you can not dial down specific PID control parameters of the GPS like you can with MK. Although dialing down GPS parameters are not really an ideal solution. DJI has work around by having you rotate the GPS compass dome to normalize additional magnetic influences. For some reason doing the compass calibration procedure that similar dance that you do with MK does not do an adequate job in normalizing the compass. My only assumption is that the compass calibration does not take into effect the magnetic field generated by the motors when at flying power. None of the systems have a learning logic for the compass. Ideally the compass should only be a reference point and should be backed up by other inertial guidance or updating through the GPS as copter moves through the air. This is something professional avionics do in larger aircraft. An ideal navigation control system one would be one where the GPS position is just an initial reference. Ideally on the ground you would to ground truth the avionics and verify that Lat/Longs are correct and compass magnetic heading is correct. If not you would dial in the precise coordinates and heading. While airborne the system would correct itself using inertial sensors such as the accelermoter. An ideal algorithm would be: 1. Copter senses GPS position has moved 2. Copter compares with the inertial sensors 3. If the inertial sensors detect the GPS movement is correct then the copter corrects for the change in position or course 4. Else the copter ignores the GPS movement as an error and does remains in place This is something similar that the MK is doing with the altimeter by mixing in the accelerometer and comparing for barometric drift. A similar algorithm to update the compass for external magnetic fields while the copter is airborne and flying on a path. This would be more ideal then the copter going bat Sht crazy and toilet bowel when the compass is not aligned to copters EM influences that could not be replicated on the ground. Shaun
You done well and inspired a lot of interest and feedback. I am glad you posted the original summary personally.
Hey, now that I also own a Phantom 2 Vision two things are relevant: 1. I keep having visions of it employing what the documentation actually calls "Go Home" (not Come Home) and I'll watch it head off towards the PRC.... 2. I had a dream that I spoke with someone at DJI. Does that count, Gary? Andy
Oh. Yeah. Oh well. It was just a dream. DJI Support : It's the kind of support that you dream about....™
I suppose you could always take the copter back to their Austin headquarters and fly it at full throttle into a window, that might get a response. Just dont hit "Biff" in the head with it, he looks like he can handle his own
Austin "headwaters?" I love it.... As you say, noooobody messes with Biff. I suspect when it does its flyaway it might even head towards Austin! Andy.
“Biff”...love it. That guy’s gotta be stopped. There’s a physical type of us copter guys that must be perpetuated, and he’s really messing that up. Holger, The Kopterworx guys, DJI engineers...”rippling biceps” has never been used in our genre, and should be avoided.