I wrote this on Facebook, but I thought I'd put it here too

It almost came out like a melancholy poem... Well anyway:

Writing a new programme... is like building a machine.
From scratch.
Out of matchsticks and paperclips. 
And you build this massive machine, and some of it has never been built before and you just have to remember how it’s done because you can’t draw; and no one else has ever attempted it.
And you think you’re finished and you step back to admire it, flip the little “on” switch you made and it whirs and clanks and bits spin around and then it prints out a bit of paper with a picture of a duck.
And what you really wanted, was a list of the names of former US presidents...
but you have a duck.
And then you think... Why is it a duck? What part is making it a duck? Is it the printer? Or the bit that sends the instructions to the printer? Or the bit looking in the encyclopaedia? Maybe it got confused and looked up ducks. Or maybe it’s not even looking in the encyclopaedia and it’s just found a duck photograph inside the leaves of a book, and used that? 
So you ask it some questions. But all it can do is print out numbers. The numbers tell you about what it’s trying to do, but it’s a machine and so it’s very bad at explaining.
And you take it apart, and you look at every piece...
and eventually...
after hours...
you find the problem.
You put a toothpick in the wrong place.
ONE toothpick....
and you move it 6mm to the left, and you see from the numbers that... ahah! It’s looking at the correct pages now! No more ducks!
And you put it all back together,
and flip the switch,
and you get a picture of a hat

UAV Demo Vid

I made a video. Lucky me! Not much of my work in it, but it was a nice distraction from the day-to-day.

Three Minute Thesis

First, quick thank you to everyone who gave me supportive and thoughtful comments on my last post.

Second, a few months ago I competed in the Faculty of Physical Science and Engineering "Three Minute Thesis" competition, where I had only 3 minutes to outline what I do and what my research represents. I managed to come away with £50 and a second place position, and now (no thanks to the people who uploaded the video without telling me) my little talk is available online. Enjoy!

Computers and Coal-coloured Canines

Despite being something I very rarely mention to all but a few close friends, I feel rapidly that I'm beginning to need more than one sole outlet for the single biggest obstacle to the completion of work in my PhD, namely, that for the last four years I've suffered from what most people call Depression, and what a different sort of Doctor would call Major Depressive Disorder.

There are plenty of excellent sources, valued reader, that explain the precise details of this condition far better than I could possibly attempt; and a short jaunt to your favourite search engine will surely confirm this. Nonetheless I feel compelled to add as best I can some particulars of my situation and how it pertains to my performance (or lack-thereof) in my research at this time. I include a few silly cartoons I made in moments of despondency. Make of them what you will– I appreciate some of them may seem almost narcissistically self-piteous, but I hope they might serve some purpose in explaining or allowing people to empathise with this condition.

~~~~

The popular comparison for depression is that of a black dog– the larger and more cumbersome the better– draping itself across your back or lap and sapping you of the energy and will to continue in the pursuit of daily things. I have mixed feelings about this analogy: for on the one hand it conveys the almost physically tangible "weight" of hauling around a brain deficient in serotonin and intent on ruining your day, while on the other it equates the condition to a creature many of our species find adorable and cute.

As such, in my own mind I've always preferred to imagine a more amorphous blob. A sort of sentient lump of tar malevolently swamping your work and your faculties of reason. While I appreciate it may be impossible for some to consider something affecting you very pertinently in your higher mental faculties, it is something worth keeping in mind whenever a friend confides in you that they have such a condition. It's still a physical ailment: Something in my brain isn't working properly, and it seriously affects my ability, in turn, to work. I would not dare to pass judgement on similarly afflicted friends, as I have heard some do, that suggests they are merely "lazy". In the same way a severed leg would seriously impede one's ability to run (unless replaced by a suitable prosthetic), an abnormal mixture of hormones in the brain seriously impedes one's ability to get anything done (for which, perhaps sadly, no such prosthetic can provide a cure).

This need not even be serious or important work. One of the reasons I feel privileged to know friends who can empathise with this rather stupid condition is that some days you really long to share with someone that you managed to brush your teeth, and are feeling distinctly proud of this achievement.

Ultimately, aside from lacking any kind of feeling of motivation to begin a task, I have found that one's own inner-monologue often confounds the matter. Consider a state of lowered mood, which has prevented you from achieving a pre-determined goal of fixing your buggy code by a given day. Now consider the feeling of failure gained from such a missed deadline, and quickly one can appreciate the sullen downward spiral of self-doubt and misery which results. Again, this may sound hyperbolic or even self-centred, but its veracity cannot be fairly doubted and is supported in lines such as that by the ineffably insightful Stephen Fry when he describes the "blackness, lethargy, hopelessness, and loneliness". Notice the inclusion of the word 'lethargy'. 

In the event I alternate between feelings of vague contentedness with the progress of my Transfer Thesis and relevant research, and almost overwhelming negativity wherein I convince myself I am incapable of any significant achievement or completion of my Doctorate. For now, at least, here I remain: holding on to the hopes that I will succeed despite this encumbrance and with the support of those I can rely on, and that I will not succumb to the terrifyingly real prospect of having to stop what I'm doing and move elsewhere. 

I might have just wasted ten minutes of your time with this incoherent ramble, for which I apologise, or I may have provided a tiny glimpse into what I think about every day that I sit in this office. Either way, and whether or not I know you personally, thank you for taking the time to read all this and give me an opportunity to voice myself in this small way. 

2013 in ... one post?

Whoops. So it seems I've managed to neglect this blog for almost an entire year. Not intentionally of course, it's just other things seem to take precedent. Anyway a bunch of progress is being made both in my own tiny little section of the UAV-algorithm field, and with UAVs as a whole.

My Stuff
Post progress-report (not transfer thesis: that's next year) I've been thinking more about what first responders actually want or need in a disaster situation. I had set up a meeting with Rescue Global (a sort of... real-life International Rescue) but they had to cancel after needing to dash off to the Philippines. As excuses to miss meetings go, I think "biggest Typhoon in history" is one of the better ones. Hope all is well out there.

I honestly would love to know that work I've done could help in these sorts of situations. Source: Dailymail

Anyway, I came across this interesting assessment from the Red Cross which outlines a bunch of goals and implementations of what is done/what needs doing after a disaster strikes. This actually helped me solve a key question in my work, which goes something like this:

If you're REALLY sure that there's people, in a location, that need help, do you need to bother sending a UAV for imaging anyway?

Put another way: are we taking images for the sake of it, or to work out where people are? Because if it's the latter you can actually ignore parts of the map where you're certain there are people, since you know already.

It turns out, from the wording of the report, that there's merit in imaging anyway: the wording suggests emergency responders value being able to see and assess what situation the victims are in even if they know in advance where they are. That makes sense to me, since it might inform what sort of response is needed (helicopter? boat? ground crew?).

Anyway my ideal system for controlling the UAVs now works something like this: Given an area, with some sort of prior belief of where people are, and some sort of belief about what danger they're in (quantified as an expected death-rate), and given that taking images of these people will let them get rescued more effectively, what's the optimum route to travel around the space, taking pictures, with multiple UAVs, to minimise the overall death rate?

I think the main motivation for phrasing it like this—apart from the fact no-one has done it before and PhD (if nothing else) is supposed to break new ground—is that I'm keen on producing something which is actually practical and useful, and not just an interesting exercise in computer science. I'm increasingly convinced that the idea of discretising the needs of disaster workers into "tasks" is not particularly reflective of the more cohesive picture that can be painted of a disaster area.

Anyway the exact mechanism for this has yet to be decided, but it'll probably be some sort of Monte-Carlo Tree Search with factoring to account for UAV co-ordination. So here's hoping for a paper early next year.

Other stuff
Seems that UAVs have made the news in a few places recently. There's the RAF trying to soften their image as all-purpose killing machines in this BBC article for a bit of interest. Much more bizarrely, there's the recent revelation that Amazon are thinking of using UAVs to deliver packages:

In news next year: People now hunting for Xboxes using rifles. Source: Amazon

On our end, we've also had the Beeb round to film some of our stuff for an upcoming episode of Bang Goes the Theory. I'll post the link up here once it airs, and I might even be in the background. Somewhere. Very briefly.

Anyway there's more out there if you look for it, and it seems UAVs are going to be big business in years to come. Hopefully that'll mean more cheap drones for us to buy and test on :)


I promise I'll be better at updating in the New Year. It'll be a resolution. Or not, since those are so often discarded. Anyway until then, have fun and enjoy your not-yet-delivered-by-drone presents!

Quick NY update

Haven't had much to say recently, but I doubt there are that many readers out there desperate to hear about my every move. Short summary time, then.

Basically I've spent the last few weeks trying to get my head around ROS, a software package for coding operating protocols, algorithms, navigation, message passing etc for robot hardware. It's good for simulations too, which is what I'd like to have done in a week or so. I suffered a big-ish setback when I found out the version I was using was obsolete and had to start again with the new build environment called "catkin". I'm guessing the changes are mostly under the hood because it seems somewhat less intuitive than the first version.

So now I'm spending my time trying to work out how to get Max Sum into a form suitable for simulation, which is quite daunting given that I have no experience in software engineering before now and with multiple interacting parts to consider, that's very much what I'm faced with. The sums and functions themselves aren't all that complex, although translating my understanding of Max Sum from a simple graph-colouring exercise into task allocation is proving trickier than first imagined. Let's see how it goes.

-Chris

Latest ideas in brief

In light of the continuing plans for the Mosaic project (check out the new website here) I've been trying to flesh out more of an idea for what I can contribute to this field in the coming years. Thankfully with confirmation from my supervisors that it's not a stupid idea (always worth knowing!) I'm beginning to build more of a concrete plan of what I can (at least try) to implement.

Mosaic project logo. Not representative of our choice of UAVs...

The logic behind it:
It looks very much like the Mosaic demonstrator we're planning for next summer will consist of heterogenous UAVs: specifically fixed wing gliders and some form of 'copters. Given that these clearly have very different capabilities, speeds, durations in the air etc; how best can they act as a team to find the targets in a space? There has been work on this area already, specifically in coalition formation, but there doesn't seem to be much emphasis on a message-passing hierarchy between different forms of UAV. The kind of example I envisage is where a high-level glider does a few passes over a search area and generates some initial guesses for locations of search-objects (in real life, these might be casualties), before passing this on to the lower-level 'copters to deal with in some way, perhaps as a max-sum task allocation since the framework for this already exists. In a non-discretised case, where perhaps it would be best not to treat individual locations as point-like tasks, I'd also be interested in using rapidly-exploring random trees as a basis for working out optimal routes over a probability map produced by the glider to maximise some utility in finding objects.

Animation of a rapidly-exploring random tree. After growth is complete the UAV can pick an optimal path to follow.

Well that's the summary. Now comes the hard part of making all of this actually tenable! Back to work...