Monday, 14 November 2011

Getting the design right vs getting the right design

So today I've been looking at ways to make the text input interaction more fluid and investigating if I can able some level of error correction (i.e. a spell checker).

1) 2 hours of use off and on and my arm aches, my back aches, my wrist aches. Even with the minimal arm movement that is required, my forearm still needs supporting and to spell a 5 letter words I am still moving the focal point about....6 inches across which is enough to induce fatigue over time. If I had more time I would do an about turn and look at just using a single finger (although that reintroduces the segmentation issue which the pinch technique solves)....

2) Writing without visual feedback is more taxing than I had thought. I originally did an experiment which involved people walking and writing at the same time as a "proof of concept" exploration. I suspect I had the task wrong though - I should have had them do it blindfolded! Luckily I've still time to repeat that experiment.

3) The limitations of the hacked together prototype are becoming rapidly apparent. Converting points to words introduces a significant lag into the "glue" application ( and the poor performance of the fiducial tracker both in terms of the "jitter" and frequent loss of acquisition is making this painful.

4) On the positive side, I am both impressed and disappointed by just how well the air-writing can work. Its best with visual feedback but on single letters performance is excellent. For cursive handwriting performance is....variable. With visual feedback I'd estimate 80% of words are in the alternate spelling list. Without feedback that drops to maybe 50%. I've a small word list, I need to benchmark obviously.

5) Mobility. The need for compensation due to movement is very apparent, Discreet gestures are just not registered, recognition rate suffers immensely, reliability is terrible - very very unimpressive performance.

6) I had intended to explore the pico-projector more over the next 2 weeks. Sadly the MHL link between my Samsung SII and the projector is unstable meaning if I do anything I need to hook up the laptop...except I have heat related issues with the laptop causing it to crash if I put it in my bag for more than 5 minutes :/ Added to this, battery life on the projector is about 20 minutes on a good day.

All in all, I know this is a prototype but its far less impressive than I had hoped for unless I manipulate conditions extensively. Still that's about par for the course for a V0.1. A good learning experience so far, probably not shaping up to be the greatest Masters thesis ever...but then I knew prototyping was risky.

In other words I have to wonder if this is the right design for this type of interaction. Its hard to tell how many of the issues I'm experiencing are to do with the technology verses issues with the approach I've taken overall. Thats a different kettle of fish though!

Wednesday, 9 November 2011


I've been busy with whipping my literature review and methodology sections together for the last few weeks (with the occasional diversion to tout the surveys, still a very low response so far *sadface*) and I'm heading towards crunch time now where I'm going to have to bring everything together for a draft version early next months.

Since I'm now more in a documenting than development phase I've little work done on the prototype apart from to add recording/playback capabilities so that a session can be "recorded" and then I can explore if changes to the gestural interface improve recognition (although that isn't a major aim at this point).

Again, a quick plea to anyone reading, just a few more responses to the gesture and display surveys and I'll be able to start my analysis for that data so if you have 5 minutes it would be greatly appreciated.