Max Bruner's Posts (4)

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R10 Maiden flights and other videos!

Until this weekend, we have been testing our newer frames with our older Forebrain/Seraphim flight controllers.  But this weekend marks a milestone in R10 development with the first time we were able to fy the full R10 system (the R10 frame with the newer Thalamus flight controller).

Above is a video of a full R10 system flying Thalamus at 800Hz quaternion/attitude update and 140Hz PID loop.  In this video, the old Forebrain/Seraphim units were still attached to allow us to quickly switch over and compare performance.  In the final systems the battery is mounted top-side instead, and the cables are tidied away with the white lycra cable tidies.

And below are videos of the first outdoor test (excellent test flying conditions with no wind) at 800Hz quaternion/attitude update and 400Hz PID and PWM output.  We've not got the tuning just right yet, the yaw is overtuned in this video, and oddly there's some instability during descent which was not observed in the R7 ROFL systems running at much lower rates (possibly something to do with mounting the battery top-side).

At the end of the above video, Henry misjudged the landing and flipped the quad.  He should have trusted the pneumatic landing dampers, which are there specifically for the purpose of allowing safe and smooth landings.

 

On a side note, we also got the prototype static camera mount frames, and are in the process of testing this.

20121101_110023.jpg?width=400

We also bought one of these FPV pan/tilt mechanisms to play around with, with the idea of turning it into a stabilized gimbal for a very small camera (some of our Kickstarter backers suggested the HackHD)

In any case we're developing a gimbal mount specifically for the R10, here's a quick mock-up of what it would look like,  note that this is a mock-up/proof-of-concept, and it was thrown together in about 20 minutes from scrap aluminium frame parts, and there was no design considerations for vibration.  The one that we do design will of course deal with such issues.

Some people have asked whether side-mounting cameras like this is an issue, I think most people here know that a small I-gain in the PID loop will dynamically re-balance the quad for uneven loads like this.  We weren't going to show this following video until we found a pair of giant scissors so that we didn't have to chase the quad around to cut the string, but here it is anyway for your enjoyment.

Not much else to mention at this point, there's plenty more information on the Kickstarter page which will soon be winding down, and we're nearing the 1000% funding goal, we might just make it!

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When two kickstarters meet...

...something beautiful is born.

3689483745?profile=originalJust this week, after a suggestion from one of the Kickstarter backers, we are now collaborating with Quantum Robotics, pairing our R10 Advanced Quadrotor system with the Quantum Robotics Q2 XBee Handheld Controller, a programmable, customizable and hackable XBee controller that you may have seen before

There's more details here: http://www.kickstarter.com/projects/1101297082/r10-quadrotor-powerful-inexpensive-and-customizabl/posts/330859

The R10 Advanced has a GPS/XBee module that handles autopilot and telemetry, which can be used as an alternative to a regular RC transmitter (or used in conjunction with a regular transmitter to send telemetry to a laptop)

3689483807?profile=originalBut we realized that it also makes it completely compatible with the Quantum Robotics XBee Handhel Controllers (we'll ensure that they're fitted with the correct XBee units), which would be able to send the R10 manual control information, either using MAVLink version 3's MAVLINK_MSG_ID_MANUAL_CONTROL, which is what the R10 is set up with currently, or by some other protocol.  We'll be working closely with Quantum Robotics to see if they'll support the latest version of MAVLink on their controller so that it can be used with other craft.  We also want to use the display for battery levels.

The extra potentiometers on the transmitter would be excellent for fine-trimming controls, tuning the craft's flight dynamics or sensitivities on the fly, or controlling extra servos, like altering the default position of a stabilized camera gimbal!  So this is definitely a very exciting opportunity for us, and we will be exploring the full possibilities soon.

The VERY interesting thing is that with all the extra buttons and switches on the controller, along with the mesh network/broadcast capabilities of the XBee, there'll be a possibility in the future of controlling a fleet of craft from a single Quantum Robotics Q2 XBee Handheld Controller using the buttons/switches to toggle control between individual quadrotors (the other quadrotors would have to be put into GPS hold).  Could potentially allow a single person (presumably with super-human multi-tasking capabilities) to control a load of quadrotors to film an event from all different angles.

3689483920?profile=original...Or it could be a recipe for disaster.

This is something we're keen to test out, but we'll keep that for later.

We've added a pledge level on our Kickstarter that would let people grab an R10 Advanced with a Q2 XBee Controller (we'll be fitting the controller with an XBee ZB Pro needed for compatibility).

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The story of R10 in pictures and videos

Hi all, I'm glad to announce that the R10 kickstarter so far has been a great success, we reached our funding goal within 30 hours, and there is still interest.  So I thank all of you here at DIY Drones, I know some of the community here have supported us too, so thank you.black_rofl.jpg?width=400

I wanted to share with you guys some of the history and development of the R10, including crashes, dating back to the quadrotor that was called ROFL (pictured above) from sometime in 2011.  Some of these videos/images you may have already seen as they were posted in Henry's bloghere on DIY drones at the time.

For brevity, I've only selected some of the key highlights, the rest of the historycan be found on our website.

These were some sketches that were made of the frame, and a few prototypes made of palstic and card.  The aim was to minimze the number of components needed to build the frame, so a slot-together design was chosen, and that design remains core to the R10 frame today.

2011-07-03%2000.15.27edit.jpg?width=400The initial testing was exeedingly difficult, at that point three things had to have right for anything to work - the electronics, which were completely new; the frame, which was untested; and the software, which was written from scratch.  Unsurprisingly, mistakes and erroneous assumptions were made, which meant that things didn't work as well as planned at the start.  The test rig was built in a garage using scraps of wood and clamps.

Eventually after a lot of head-scratching, research, maths, and frustration later, things started going well and it the quadrotor appeared to be behaving more like a flying machine than a glorified desk-fan.

I think many of you here will empathise with us about the lengths we went through to find workable tunings for the craft from scratch.  This prompted the development of an XBee-enabled version of the control board, and a debug interface was created in Qt that had data-logging, sliders, and data-entry boxes.  In this video, the quad is deliberately detuned mid-flight just for fun.

Things went well after that, however there were some persistent bugs in the flight code that caused transient unexpected behaviour, and gradual loss of control, a night flight ended in the worst crash to date, losing two motors and ESCs.

Many long nights of code tweaking, a complete rewrite of the AHRS, and new ESCs later, (Ok, I just skipped about 4 or 5 months of development time here, but just imagine countless crashes, whole bags of props smashed and a lot of swearing) we ended up with something that was acceptable

The ROFL quadrotor, and Henry make a brief appearence in this BBC News clip from earlier this Summer just before I joined: http://www.bbc.co.uk/news/uk-england-hampshire-18416111Henry and Universal Air were volunteering with TeenTech, a charity set up by BBC's Tomorrow's World presenter Maggie Philbin, which runs a program that invites schoolchildren to meet engineers in the real world and encourage them to seriously consider Engineering as a career.  (BBC's facts are wrong, Henry was at Cambridge University, not Oxford)

3689483090?profile=originalHenry set up a "flying tent" which contained the ROFL to keep people safe from any prop breakages, and the ROFL quadrotor was also "kid-proofed" with a large padded yellow ring.  The kids were allowed to try to fly the quadrotor.  It's a nervous experience letting kids mess around with a $400 quadrotor, and some did manage to break parts of the quad despite the extra ring, but most were able to fly the quad thanks to the ultrasound altitude-hold and magnetometer-based "simplicity mode" (which allows you to yaw as much as you want and still have the quad roll or pitch in YOUR reference frame: stick left makes quad go left, regardless of yaw).  There were even some who were surprisingly adept at flying without the altitude hold, we can see some promising drone pilots here.

3689483207?profile=originalAbove was our showcase stand

And now, with even more code tweaks, a completely new flight controller, new operations in the US (that's me!), we end up with the R10 quadrotor system, which is currently on Kickstarter

r10.jpgHere's an assembly video:

What might not be clear in this video is that the flight controller is screwed into the side of one of the frame parts near the center, the flight controller doesn't actually feature in the video because we made the video before prototypes of the flight controller was available.  And the ESCs have been heat-shrunk directly onto the aluminium frame for better heat dissipation.

I hope this has been informative!

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Sub-$300 quadrotor kit released on Kickstarter

R10.jpg?width=400
Hey guys, thanks for so many helpful and kind comments in my last blog post. 

Our Kickstarter project was just accepted after a lengthy review process! So I'm glad to announce the R10, a sub-$300 quadrotor kit aimed at hobbyists and academia.

Take a look! http://kck.st/T6e7mu

And our website: http://www.uair.co

This is my first time with a Kickstarter project, so any thoughts and suggestions very welcome and appreciated!
Max
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