Markus Jahn's Posts (4)

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Here is video of first flights with the new lighter Hashcopter. PIDs make it a bit agressive and unstable because of reduced weight. Also you can see the massive camera flying with the copter.

Story goes like this:

I had a bad crash after few hours of flight time with Hashcopter. Crash was caused by flying the battery too empty and one off the ESCs cutting power off. The copter is capable of landing with 7 motors but I made a mistake flying to the direction of the broken motor to get it closer to pilot. This caused it to lean on the corner with no power and from that it couldn't recover, flipped and crashed from 20 meter height. Frame bent badly and one of the motors was never found. Fortunately most of the electronics survived from the crash. Lost only two motors and one ESC.

For some time had been thinking how I would change things if starting to build the frame from scratch. This was the perfect excuse to start all over again. So here are the changes made to totally the new frame:

- Used 10x10mm tubing with 1mm wall thickness. This saved 160g of the frame weight and frame is still strong enough for all practical purpose.

- None of the wiring anymore goes inside the tubing. These things are always being repaired and taken apart for some purpose. I don't want to do any extra soldering just because I need to get something detached from the frame.

- Made much lighter landing gear from 6mm aluminium tubing. Saved 60g from that.

- Built really simple Camera mount with no servos from 6mm tubing. I take only still images and usually the camera stays in one position or can be manually turned on ground.

Overall I got the whole copter over 400g lighter and that means minutes of more flight time. Overall flight weight after lightening is still 2700g. This includes 730g of camera and 530g of battery.


And here is a nice sunset shot from repaired copter:


Earlier parts of the story:

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Arducopter with 8 motors - First aerial photos


Had again a really nice saturday flying with my Hashcopter. Took first images from the copter with my 800 gram camera. Pictures didn't turn up to be anything spectacular but copter flew nicely at high altitude and was very controllable. I'm still waiting for parts to arrive for my camera stand and FPV equipment. For that reason camera stand was just taped to nice position and images shot by feeling.

I actually had some difficulties with cheap ESCs not arming the motors properly. This was due to it being -25 degrees Celsius temperatures and electronics just needed some warming up occasionally. Actually so did the pilot. Eventually one of the ESCs broke down and flying was over for the day.

Because ESCs did some tricks on me I accientally ended up testing what happens when one of the motors shuts down. I was landing the copter still hovering at around 20-30 meter height when one of the motors just stopped. It was nice to realise everything was still controllable and I was able to land to copter nicely to a snowy field. It could have been flown with just 7 motors despite the heavy camera hanging under the copter.


3689390554?profile=originalAll saturdays pictures with better resolution:

Previous two parts of the story:

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Weight testing of 8 motor Arducopter

Been flying more with my eight motor version of arducopter. Lately I've been attaching different weights to see what the copter is able to carry and how long. Results have been exactly as i presumed them to be. Flying with 4-cell 5000mAh lipos it can fly with 800-900 grams of weight aboard and flight time will be around 7-8 minutes.
After the weight tests I've been trying to get the AH and PH working. Those have been bit dissapointing features after getting used to precise and accurate way the German Mikrokopter keeps its place when told to. But I still use RC2 version of the code and am in the process of getting the AH+PH PID settings right. A wiki page of adjusting your AH+PH would be appreciated.

One lesson I learned the hard way is protecting your APM+IMU from moisture. One day I crashed the copter upside down into a snow bank and the snow melted on top of circuit boards. This fried the APM and I had to order a new one. DIYDrones store came to rescue and just 4 days later I had a new APM and my copter was again airborne. Big thanks to them for saving my weekend and making this video possible. Way to prevent moisture from destroying the circuit boards is covering them with protective spray.

Next step for me is to get my camera stand repaired. I smashed the servo on it during one of the flights. After that it is time to take the first aerial photos with the Hashcopter.

Part one of the story:


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Arducopter Quad with eight motors.


I just got finished my octocopter with Arducopter electronics. It is built to carry DSLR and should fly 7-8 minutes with 1000g payload. Copter is actually just a quad which has two ESCs and motors on each end. It proved to be really stable platform on first tests last weekend.


I fly with 5000 mAh 14.8V Lipos and have eight 750kv/100W motors. Still the flight time with such a heavy camera will be short. But actually from previous experience I know 5 minutes is long enough for photographing a target. After that you can land, change battery and make a plan for next 5 minute flight.


Images of my build can be found:

and first flights:

Youtube -video shot from another Oktokopter:



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