Bus Pirate, ahoy!!!!

A very busy time recently so not too much drone development, however here's something fantastic!

I'm having a trouble with the sensors, no sensors then no flight :(

Why are they not talking to the Gadgeteer board?

• Is the sensor faulty?
• Is the wiring wrong?
• Is the communication protocol not setup correctly?
• Is the interface software on the Gadgeteer board wrong?
• Or something else or a mixture of some of all?

Oh no what to do?  

I looked into some analysis tools, wow they are super expensive at anything from $1K to silly money!

Then I stumbled across something fantastic called a "Bus Pirate" from Dangerous Prototypes :)

What does it do?  It allows you to hack/monitor a communication stream from any device ... yes quiet dangerous! Also very handy :)

With this little monkey I should be able to isolate the problem and get the system going!!!  Oh, and at £20 (approximately $30) it is a bargain too :)

I2C Scratching my head

Back in the swing of the development after a time away and now scratching my head!

To recap, where am I ... sensors!!!!  Sensors are everything so the lovely drone knows what is happening.

The problem is that I need loads of sensors and not enough ports on my Gadgeteer board to connect them all.  The cunning plan is to network them together with the I2C protocol.

I'm having a big problem though :(

I just cannot get the a single sensor to talk to the Gadgeteer board!  

Not sure what to do next.

I've double checked the soldering, all good.  I've ensured the wiring is correct, all good.  Resistors on the I2C and Clock lines are good.  The C# code module code is super simple and no joy.

I think I'll have to buy an I2C Gadgeteer component just to check the module code is correct.

Soldering fun

Finally back from my travels and back into the Drone :)

The Gadgeteer Prototyping board from Love Electronics allows a connection from the Gadgeteer main board into your own electronics.  You have to create your own Gadgeteer model however that looks relatively simple.  Fantastic!  

I have the sensors boards which I'll breadboard into the Prototype board for flexibility. I'm going to first try creating a Gadgeteer Gyroscopic sensor module :)

So I have my lovely sensor board from Love Electronics, time to solder some pins to it.  It's been quite a while since I've soldered however once back in the swing it was OK ... ish :)

Top tip for anyone, get the right end for your soldering iron!!!  

The original one was a chisel type which I discovered was too thick, then I tried a pin point one.  Much better, although it took far too long to transfer heat into the solder.

So I tried to solder the pins to the board, it was OK.

Not the best soldering however it was all electrically OK.  Yes now the pins are on the board!

Now to get the sensor onto a breadboard and hook it up on the Gadgeteer prototyping board.

I thought I'd tried another tip for the soldering iron.  Yes a thin chisel was the best :)

The jumper strip had to be soldered onto the prototype board and that was a dream with the new thin chisel.

End result: I now have my electronics for my Gadgeteer sensor.  Time to write the module software :)

Daisy, Daisy ... give me your answer do!

One of the problems concerning me was, I have many sensors and not enough connectors on the Gadgeteer Mainboard ... what am I do to?

I'd seen that the Gadgeteer board has I2C (pronounced "I Squared C") and oddly years and years (11 to be exact) I'd done some I2C development.  Basically it allows a master controller to talk up to 126 components.

Fantastic!!!  The question is how to connect I2C breakout boards to a Gadgeteer main board?  Thankfully the book Gadgeteer book I've been reading has all the information :)

Here's the plan, I'm doing to create my own Gadgeteer module.  Physically it will have three senors on it that are all connected via I2C.  I'll then write the module software so the Mainboard can connect to all three via the I2C.

Sounds hard however the module software is easy looking.  The tricky part will be the initial configuration of the sensors however once that is cracked it's happy days :)

Best of all, I can create my own modules that link to further modules.  Gadgeteer calls this "DaisyLink" which seems to be an implementation of I2C for talking to multiple devices thus removing some of the complication for me.  Great one Microsoft :)

First step, create my module ... I'll do something simple, not sure what yet :)

Yea, electronics arrive!!!

Woop woop, the electronics are here!!!  That Argon R1 is a thing of beauty :)

Time to start learning :)

Also, Love Electronics have been a top company.

Communications has been fantastic!!!  Answering questions, keeping me informed on the delivery and being genuinely nice all round.

A pleasure buying from them! 

Gyroscope Arrived

First package from Love Electronics has arrived.

I'm now the happy owner of a 3-Axis Gyroscope and super looking forward to Love Electronic's Argon R1 arriving sometime tomorrow!

Arduino ... I've learned you could save me!

Ummmm, I think I'm mistaken about the Arduino system ... learning lots :)

More clicking about I see you can develop for it, excellent!

Arduino programs in C rather than an object orientated language so I'm still better going with the Gadgeteer board ... really a no-braining, C or C#!!!!

This complicated autopilot system will be much easier in C# however a few ideas are starting to hatch!

Perhaps, I can use the Arduino system for connecting all the sensors to?  Perhaps as a sensor pre-processing board?  Worth thinking about :)

Autopilot Thoughts

The motor and controller thoughts are going around in circles, let's try something else.

Back to the Autopilot ...

This was a lovely thought exercise!  Super enjoyed this!  What does it need to do for itself?

Basic "Stuff"

Take off and then land itself.  Doesn't sound that hard: power up the motors, hoover a bit, lower the power a bit and gently glide to the ground.  Easy?

Ummm, the tricky bit is balance!!!  Forget the wind for a second, in the real world the motors will not be 100% the same, neither will the propellers (another thing I need to look into) and the drone won't be perfectly balanced.

I can't help, the drone is meant to be autonomous ... will need to balance itself.  I'll need cool sensors :)

Luckly me, the Gadgeteer platform has loads of sensors.  Gyroscopes, that's the ticket!

I'm wasn't too sure how many I'll need, perhaps four gyroscopes on each of the drone's arms?  Perhaps just one gyroscope in the centre is fine ... haha this is the real world :)

I don't really know but that is the fun of this project, I'll just have to experiment :)

Hovering

Will the GPS sensor be enough to maintain position?  Ummm, I hope so, to save my money, ... yet this is the real world!

We've all seen our phones and sat navs go crazy when the GPS signal isn't great.  Normally we cope ... so what sat nav goes crazy, I'm still driving the car.

My problem is that the drone is driving itself ... a old wise computer says, "Rubbish in, rubbish out".  How noisy is GPS data?

I need accelerometers!  Why?  The drone could be completely balanced yet falling.  If the GPS data is lost (or bad) then it's crash time!!!  Yes, accelerometers seem a good idea :)

How many, who knows?  I'm sure someone knows, but it's not me.  One in the centre is a good start but perhaps one on each drone's arm, that might help on complex flight ... ummmm more fun research!!!

Landing

My ideal super-do-per drone will have ultrasonic range finding tech on board and maybe pressure pads on the landing runners :)

I'm just concerned I'm over engineering this from the beginning.  When I build this machine, there will be a lot of testing.  The R&D phase will be in relatively ideal conditions and landing "should" be OK.

I need to limit the scope, controlled landings in non-ideal conditions is for later.  For now, GPS and accelerometers will do!  I hope I don't regret that :)

However, ultrasonics for landing is a cool idea :)  Loads of questions are firing in my mind ... I'm going to open another page on this blog just to document them ... please comment!!

First Day - Impossible to Possible

Wow, what an amazing day!!!

I really still don't know what I'm doing, however now it must be possible!!!

• Who would have thought you can buy quadcopter airframes on the net?  
• Who would have thought there's "plug-n-play" smart electronics & sensors you can buy?  
• Motors and Propellers all easy to get.

All the key parts are available, how exciting!!

There's more research to do:

• Which motors?
• How do I power the motors?
• How do I control the motor's speed?
• Which airframe?
• What sensors do I need?
• What "things" do I need in the autopilot?
• And probably many more ... that will do for now :)