It looks pretty good, but don't know will it open source the PCB files.

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Very impressive. This is exactly the sort of innovative derivative design that open source is intended to inspire. As long as they adhere to the license terms and release the design files back to the community, I'm all for this. 

Although I am impressed by the housing with internal IMU damping (which I like, being a former NAZA user), I am surprized that they added the Baro sensor as well (DJI doesn´t) on the IMU board. That means: No foam possible anymore.I hope that this doesn´t affect ALTHOLD.

Also the Ali sellers do not mention where the connectors are available or if included. ...Due to the lack of  SHARP TV recycling...this is my main concern..

The displacement of the dampened imu will be so small I doubt you'll have any failure of the connecting ribbon. It doesn't look like there's enough mass for vibration dampening of the imu. Was a vibration analysis performed? What is the dampening frequency and does it correspond to the frequency of a typical motor? I know its inconvenient to dampen the entire pixhawk unit but the more mass the better unless you have a very soft mount.

fully agree with you sixtimeseven!

I worked for a manufacturing company in the US around 10 years ago, we began to outsource some of the work to both China and Mexico. Eventually we shut down the plant in Mexico, due to quality and manpower issues (when a better job comes around the good people jump). All manufacturing was then done in China with much better quality and less manpower issues.

Wow, this is a really stunning design! I love the isolated IMU and aluminum casing, that just screams quality. I think for the pixhawk v2.0 these hardware design considerations should be applied. It will make the Pixhawk the flight controller to beat. That in combination with better connectors would make this a true game changer. Impressed.

I am wondering if we could add weight to the isolated IMU (lead or something similar) to improve the vibration dampening effect?

It would depend on the resonant frequencies within the chassis, motors, IMU etc. The amount of weight you add would change with every setup. Adding an amount of weight could make the IMU resonant at the same frequency as another major one present in the frame. On the other hand, if you do it right it could be very effective.

If I were going to try, I'd measure the frequency signature of the copter, the try and make the IMU most resonant at a frequency that as different to the ones in the frame and their harmonics as possible. Its tricky which is why I wouldn't bother.

Jethro -

Opinions of some quadcopter gurus aside, the cure for vibration is NOT to simply add weight to the resonant mass. The recipe for vibration damping is to find the correct amount of preload to the dampers to move the resonant frequency out of the expected operating range.

Adding weight is ONE way of adding preload; it is an effective one as long as the flight controller is never expected to operate at more than 45° or so from horizon. Much more than that, or inverted, and the added weight becomes a pendulum which can work against you with disastrous effect.

I've been flying micro-helis for years; there, the entire heli weighs between 30-40 grams. (Yes, the nanos are even lighter; but I got into quads before they became popular) As you can imagine, even a few grams makes a huge difference in balance, power, and flyability, so using weight to alter the damping of the FC is really unfeasible.

There, the solution in general is to find a combination of layers of different kinds of foam mounting tape, then add a little preload by wrapping a rubber band around the whole FC and frame.

With a suspended module like this one, the solution I would seek would be to keep the resonant mass as small as possible and adjust how tightly the elastic bands are stretched. This will alter the resonant frequency just as tightening a guitar string. Other avenues to consider would be application of silicone RTV sealant across the elastic bands to alter their resonant frequency.

Of course, if mounting on a large quad that can handle the added weight, it may be simpler to just mount the FC to one of the existing popular vibration mounts, and enjoy even greater stability due to having two layers of vibration damping.

My current experiments with this $5 vibration mount foam-taped to my FC are VERY promising, even in acro mode with inverted flight. The design stretches the rubber bushings slightly, which provides a certain amount of preload. So far, it is very effective, and there is no "flop" movement when transitioning to inverted flight as one experiences with the AVDome.

I think this FC, mounted to that vibration mount, could be a vibration "killer combo".

But first... before we go doing ANYTHING that alters its vibration damping characteristics, we REALLY need to get them in our hands to do some baseline tests.

Come on guys... you know you have our attention. Now it's time to deliver some product!

Paul

I like this. Great to see alternate suppliers for this gear. As Chris states, we should see the open source files available as well...we hope :)

I lost my SW when my transmitter LiPO ran out of juice and after RTL the plane's GPS went haywire.. I suspect its because of the vibration (due to the 3/4 auto max throttle) -- I was using an APM2.6, the pixhawk is supposed to have an improved filter..   At any rate, looking forward if somebody is able to get one and test?  according to the aliexpress the Cuav is available this month.

Looks like the cuav does not have redundant sensors:

CUAV:

ST Micro L3GD20H 16 bit gyroscope
ST Micro LSM303D 14 bit accelerometer / magnetometer
MEAS MS5611 barometer

compared to the 3DR version:

ST Micro L3GD20 3-axis 16-bit gyroscope
ST Micro LSM303D 3-axis 14-bit accelerometer / magnetometer
Invensense MPU 6000 3-axis accelerometer/gyroscope
MEAS MS5611 barometer

Like others have stated, the Chinese are building so fast that things like structured software & the documentation process get left behind.

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