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Posted by gervais | Apr 19, 2016 @ 10:17 AM | 8,481 Views
Robocat 270 with Pixracer Flight controller: The new Pixhawk FMUv4 Generation arrived

The Robocat 270 is a small quadcopter design, rather meant for cruising than for racing, still a perfect trial base for the Pixracer autopilot. It is heavier than a typical 250 racer, but offers a lot of space for add ons and bigger batteries up to 3S/2200mAh for reaching a lot of waypoints. Its an robust small quadcopter for beginners, very well visible for older Pros as well.

ItŽs so easy: Robocat, Pixracer with PX4 Software and QGroundControl Groundstation: Build, calibrate and fly !

Mounting and Wiring

The Robocat 270 frame kits are available from several sources.Two versions: Fiber glass or carbon. The latter is coming with an assortment of aluminium stand offs instead of fragile plastic provided with the fiber glass version.

The shown kit comes with EMAX MT2204 motors, EMAX 12A ESC, pre-flashed with SimonK and 6045 carbon props. This is rather bargain than top quality, but pretty decent, considering the price. Experienced pilots, not on budget, will rather use e.g. Tiger Motors and faster ESC, even CAN versions can be used with the Pixracer / PX4 stack. Those CAN based FOC/Vector Control ESCs have the potential for huge gains in efficiency and reliability.

...Continue Reading
Posted by gervais | Dec 07, 2015 @ 09:14 AM | 14,457 Views
If you happen to own a Cheerson CX-20 or a Quanum NOVA and youŽre not really satisfied with it, but you like the size, you might want to do a small refit with a PIXHAWK or one of its clones or derivates. HereŽs one proposal, how you could do that:

Sure, thats already the modified NOVA, original pics you can see at one of those "DonŽt let the price fool you" places or at Dogdudes informative CX-20 thread.

Teardown :

What a mess. Needs some clean up. First youŽll remove the flight controller, the GPS and all the loose cables attached. Remove the so-called damping pads (underneath the FC ) as well, nobody needs that stiff stuff. Keep it all clean, since you want to throw it at the bay. Remove the fancy connector setup underneath the body as well as the two status LEDs , but keep their caps. You might want to remove the motors or the ESC as well, weŽll get to this later...

...Continue Reading
Posted by gervais | Sep 23, 2015 @ 11:08 AM | 8,344 Views
Pixhawk (PX) Compass (MAG) Troubleshooting

If the (external) Compass (MAG) doesnŽt seem to work, most users accidentally swapped SDA / SCL wires of the IČC bus.

Since most of the cheap chinese traders and their suppliers donŽt stick to common pinout assignments, colors donŽt matter and pinout or connector diagrams are often wrong.

Colors of the wires donŽt matter !

This is what users are paying for the cheap price.

However, assuming that you know where GND and Vcc (+5V) are located at your PX (fancy knockoffs require a Multimeter to find out because youŽll likely to damage your GPS/MAG or MAG if swapped), only SDA and SCL are left and can be swapped without damage.

Most of the time, the external MAG will work afterwards, if you did not try to operate a 3.3V MAG with the 5V (!) supply of the PX IČC Bus. Sometimes (like at the cheap CJMCU boards) this requires a mod .

Note: It is important to reboot the PX after swapping and sometimes a new start of the Mission Planner is required to see the results.


Quick analysis if and what is wrong or not, can be done with the Mission Planner:

This pic shows the COMPASS_DEV_ID of the PX, if just the internal MAG is visible: 131594 and the external is not or wrongly connected.

You see this picture , if you do a compass calibration and move the Flight Controller. compass 1 error is...Continue Reading
Posted by gervais | Jul 11, 2015 @ 03:20 PM | 31,084 Views
Test review DJI E305 Tuned Propulsion system: New definition of the entry level !


In 2015, the former DJI Tuned Propulsion program (meanwhile copied by several competitors) has been completely renewed with E310, E800, E1200 Tuned Propulsion kits. DJI covers all common sizes for Multirotor market now. With the new product line, the DJI Propulsion Laboratory introduced sine- wave technology and 2 way communication even at the entry level. Competitors were left behind.

But what about the popular Flamewheel kits ? Which kit is going to replace the former E300 Propulsion system ?

The answer came pretty fast, when the E305 Propulsion Kit has been announced to define the new entry level : Its brand new 2312E motor represents a significant upgrade over the previous 2312 model. The optimized electro-magnetic system boosts efficiency by nearly 7% and lowers cogging torque, which provides noticeably smoother performance at low RPMs. A newly designed motor base not only provides better heat dissipation, but is also coming with a new advanced hi-tech look. The 420 LITE ESC utilizes the tried and tested square-wave drive architecture, further perfected by DJI engineers. Based on this classic design, the 420 LITE provides simplified functions in a much smaller and lighter package than the E310. Internally, an efficient and responsive algorithm serves your platform with a high level of maneuverability and stability

This sounds great and fortunately for advanced DIY, the DJI...Continue Reading
Posted by gervais | Jun 30, 2015 @ 03:17 PM | 6,530 Views
My Phantom 3 review is finally done: Keep away from it !

Hope youŽll enjoy

Link to the review :

Some pics ahead :

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Posted by gervais | May 07, 2015 @ 01:26 AM | 7,782 Views
Hi, I just finished both english versions of my DJI Tuned Propulsion reviews :-)

E310 Review

E800 Review

Hope you enjoy !
Posted by gervais | Feb 08, 2015 @ 04:44 PM | 9,926 Views
Sometimes the Postman comes with a nice package: This friday, the new DJI E800 Propulsion set arrived. Some pics to take, review coming up. You may use the pics for your own threads, if you mention the source..

...Continue Reading
Posted by gervais | Feb 08, 2015 @ 03:50 PM | 9,588 Views
My E310 Tuned Propulsion Set with the Sinewave Revolution ESC just arrived and I want to share my first pics.

Although I have done these for my review, feel free to use them, if you mention the source :-)

...Continue Reading
Posted by gervais | Aug 12, 2014 @ 06:31 AM | 8,992 Views
Some pics out of my collection. Feel free to use them for private purposes or on RCG. It would be nice, if you mention the source. Please donŽt use them for EBAY offers or commercial purposes....Continue Reading