So it turns out that I was very optimistic about just using a gain mixing of accelerometer rand gyros than computing a DCM matrix of the aircraft rotation. So I decided to overhaul the code by creating data structures that will hold the information requires for such computation. I must say that at the back of my mind I was really worried about the computational time that these calculations will take in the small Atmega328 micro. To my surprise, provided that one sticks with a minimum of division operands, float arithmetic is actually quite fast even in an 8-bit controller. Given that this application is for high L/D aircraft and who’s mission is mainly waypoint tracking, the slow changing dynamics can be reasonably captured with this environment. The bad part of the implementation was to discover how quickly the gyro drift (especially in the roll channel) hurts the computation of the Euler angles. (See the pics below), even-though all sensor are bias compensated fro...

So I've decided with the change of the DCM matrix and PI controller for navigation to change fundamentally the code layout with the use of data structures to make more sense of the information been passed on. I also spend most of list night trying to get my head around whether float division is really such a problem. We'll based on references xxx and xxx it is. Float memory allocation is not a real issue but float division can really boggle down your code to the core of tortoise pace. So this reference xxx explains that one can find an alternative around this issue which should speed things up quite a bit.The fact of the matter is that float division should really be an exception in any type of code (irrespective of the compiler and host). A lesson well learnt.

So I've been working on a concept to help my garden grow from what it is now something more substantial. It's really tough on the lawns to have two busy dogs and not enough water. So eventually I decided to buy 12V solenoid valve ( which can work down to 7V) and design a PCB board with the necessary hardware. So this board has the capability of temperature and daylight. So with this, it will be able to switch the sprinkler only at optimum timers of the year. I'll upload more pics once the finished product is working. Which is hopefully the next few days.

So I've been working on a concept to help my garden grow from what it is now something more substantial. It's really tough on the lawns to have two busy dogs and not enough water. So eventually I decided to buy 12V solenoid valve ( which can work down to 7V) and design a PCB board with the necessary hardware. So this board has the capability of temperature and daylight. So with this, it will be able to switch the sprinkler only at optimum timers of the year. I'll upload more pics once the finished product is working. Which is hopefully the next few days.

So it's been at least a few months since I've written updated everyone of what the next plan for this project is. I realised that not being close to an open field has really dampened my motivation to fly my concepts as often as I should. So it's quite clear that I needed to find a new way for testing my custom flight controller and even though my work has taken much of my time in general, as new approach is needed. To change, I salute you.

It's been awhile since I've actually touched my project. More responsibilities at work and now enrolled in a business school makes finding time for 'real' work quite difficult. And by the way, I've been learning Android development for school (business school) so I might come up with an application for this project in the near future. But nevertheless, I've had many chances to ponder on how I can speed up the development of this autopilot. It's been quite clear that flying a 2m glider is restricted to large fields which you have to drive to only when the weather is right. For prototype development, a slow turnaround for testing is your number one enemy. Trying to fly at work is also counter-productive because then time is taken off something work is not paying for. So the decision made to change the platform upon which the autopilot is been tested. We went from 2m glider, 60cm glider and now we're going quadcopter. You may think what!!!!! You can...

Yeah that's right. Everywhere you go, including some intern projects at my company, quadcopter drones is the current trend. The marketing success is simple. It's a lot cheaper and less complex and than a comparable RC helicopter. They're virtually no mechanical moving parts (expect the platform itself). And it's perfectly suited for camera attachment. So hot combination has spawned the quacopter drone revolution. I've always been against following a trend just for the sake of it. But considering that I need perfect weather test fly my flight controller only makes sense to start modifying my code to accommodate for a quadcopter. The controls are pretty straightforward and the design is incredibly simple. Another design dev coming up!

So I decided to build a new aircraft since my 2m glider only gave me limited flying options. This is was quite a quick project as all was designed in Solid Edge including the electronics. This enabled me to work out the mass and balance throughout the design process. The total weight sits at 250g. This includes autopilot and GPS. It's designed to have external servos and a shifting wing placement since it will have various payloads like a mini VGA camera. The electronics are housed nicely in the fuselage powered by a 850mAh 7.4V battery. I've removed the redundant magnetometer in the autopilot board. Still not sure on the CG placement, but from the crashed maiden test and the fact that the control moment arm is quite small, it's believed that the C.G. needs to be further aft from the wing main spar (which currently sits on the aerodynamic center).

So finally the FAA has released its take on how to regulate the commercial use of drones or unmanned aircraft on USA territory. It's mostly good news although, some companies (like Amazon) will not be too happy. The gist of the rules are as follows (copied from here ): Unmanned aircraft must weigh less than 55 lbs. (25 kg). Visual line-of-sight (VLOS) only; the unmanned aircraft must remain within VLOS of the operator or visual observer. At all times the small unmanned aircraft must remain close enough to the operator for the operator to be capable of seeing the aircraft with vision unaided by any device other than corrective lenses. Small unmanned aircraft may not operate over any persons not directly involved in the operation. Proposes a microUAS option that would allow operations in Class G airspace, over people not involved in the operation, provided the operator certifies he or she has the requisite aeronautical knowledge to perform the operation. Daylight-only operati...

So the game space has changed. The South Africa CAA ( SACAA ) has come out guns blazing drafting regulations regarding remotely Piloted Aircraft/System (RPA/RPS). One thing was clear, this massive chaos that growing in this country had to come to an end. Already, the general population of stakeholders in the civilian airspace have a very nonchalant attitude when it comes to safety and security. So the introduction of aviation regulations towards the growing market of drones is a much needed intervention.