27 months later…

It’s been 27 months since I first mentioned a quadcopter project on this blog.  And finally, I think I can say this initial phase of this project is finished and as good as it can be.

There’s a few bits and pieces I should do with HoG just to tidy up:

  • I want to get a longer video – probably at the local park – to prove how well behaved she is.
  • I’ll try her with flight plans that involve horizontal movement but I’m not expecting any surprises there – with motion processing, a hover is just a special case of movement – if hover works, then so will movement
  • I may add the ability for her to fly in circles – that’s a little different as it involves a fixed angle along one axis and a fixed velocity along the other – but again, other than calculating angles and speeds to give the size of circle required, there’s little else to do.

I’m struggling to get excited about using the magnetometer / barometer to refine orientation and altitude – I don’t think she needs it for the purposes she’s designed.  Likewise, I’m not bothered about adding GPS.  But I do have everything I need should I change my mind.

I will probably add the laser tracking as this will give me the ability to control her:

  • 2 lasers on opposite arms pointing at the ground but slightly inwards used to attain and maintain a fixed height
  • a third laser in my hand to guide her around at that fixed height.

I hope to be able to show her at the next Cotswold and Cambridge Jams but I’ll need a lot more flights between now and then to be confident she won’t misbehave and fly into anyone.

As for now, I’m feeling a little deflated, demotivated and just a bit tired.  Time for a break.

Dear John…

Thanks for video’ing the whole of my CamJam presentation including the demo flight!

If you want to see more of the CamJam John videod, along with the Laser Cutting / 3D printing / CNC machining he offers, check it out here.

GitHub update

I’ve just pushed a couple of things up to the GitHub repository:

  • the LibreOffice presentation I gave at yesterday’s CamJam
  • the RPi.GPIO python library with enhanced hardware interrupt performance.

To install the RPi.GPIO changes type

cd ~
tar xvf GPIO.tgz
sudo python setup.py INSTALL

Then to use the improved performance, instead of calling GPIO.wait_for_edge(), call

  • GPIO.edge_detect_init(pin, edge) once at startup
  • GPIO.edge_detect_wait(pin) whenever you want to wait for a GPIO pin event
  • GPIO.edge_detect_term(pin)

GPIO.wait_for_edge() still exists as a wrapper for these 3 functions.  pin and edge are identical parameters as for the standard GPIO.wait_for_edge() call.

CamJam report

Just back from the CamJam – focussed very much on robots and robotics.  Lots of people attended my presentation and asked lots of interesting and intelligent questions, and critically, nobody got hurt during Phoebe’s well behaved (outdoors) demo.

The Foundation turned out in force; I saw Eben, Liz, Carrie Anne and Ben, though I spoke to none of them as I was either stressing prior to the demo, or chilling out afterwards (@recantha – there needs to be a bar at the next one!)

There were lots of robotic gizmos, gadgets and kits on sale – I nearly got my wallet out for a couple, and may well still (I’ll add links when I track them down).

  • a Segway style two wheeled self-balancing robot kit
  • 64×64 LED sqaure for all sorts of display / game (i.e. tetris style) usage from skpang

Big thanks to Mike and Tim for setting up a great event – I’ll be back!

Countdown to CamJam: 2 days left

I’m off to London tomorrow morning, and up to Cambridge after work, so I’m packing her up ready for her journey.

She’s probably doing the best she can given the inaccuracy of the sensors, but I’m still not quite confident she’s good enough for an indoor demo, based upon a few tuning test flights this morning.

So fingers crossed for a safe journey and a good day on Saturday, and I’ll update you on the results.

Wish us luck!

P.S. Just cheated and run her through the calibration cube again with the aim of getting the best possible set of sensor readings for the show.