Visualizing Feedback control

I wrote a jsfiddle sample as a demo for my brother’s control systems class at NAIT to show the differences between closed-loop feedback controllers – the tiny algorithms behind cruise-control autopilots, and autofocus in your camera.

I have to generalize it to a PID object and so on, but it is fun to play with the coefficients – and I learned a thing or two I’d forgotten about digital controller behaviour, like sampling error and sampling bandwidth. And as all Control Systems engineers are warned: Turn up your Gains slowly!

Ideas for feedback loop tuning games? The unicyclist? better cruise control, Autopilot lander? Fill the acid vat?

http://jsfiddle.net/jufa/gWBbV/

Scientific American – touchscreen opinion

Their take on why “touchscreens will not take over”. I’m expecting theywill be superceded in many cases these “touch surfaces” will be superceded by “touch volumes, much like the Kinect interface volume, since there is not a lot of tactile benefit to a smooth, non-responsive touch surface.

UX Trading Cards

A UX-y way of understanding all the facets of User Experience. By Dan Willis

UX Cards, Dan Willis

Suspension of Disbelief

Look at this amazing demo of silliness. I love Peceptive Pixel, and the idea behind the Windows 8 touch experience. But one does not use a vertical touch wall in real life. It is a matter of pixel density versus arm length, and while a retina-class smartphone held at waist level is too far, a 40+ inch vertical touchpanel at arms length is fatiguing and too close at it’s nominal 60dpi.

Another factor is performance anxiety – in a public space, a large interactive display effectively requires a public performance (with no privacy) and people tend to shy away from using it at all for this reason (unless they are kids!)

The real advantage of simplicity

Instagram, Pinterest.

It used to be that being a part of an elite group had a barrier to entry. You earned it up front then gained entry. Now the elite group has no barrier to entry, and the payment is essentially what you do within the group. The group itself has to be known though to be an elite – to be desirable to belong to, so usability is key – the more people use it, the more people want to use it, simply because the content is generated by the group.

However adding too many feature introduces new barriers, in terms of usability, and more importantly in terms of the new language of the group –  instagrams language – square photos, and photofilters, with like+comment+follow functions is something familiar and easy to pick up (hey, friends are familiar and social networks can now just bootstrap from one another). If more features were added, this would stratify the users into subgroups, which is not really desirable when trying to build (and sell) a unified community. Keeping it simple allows a faster community build, a more cohesive community – something that more features cannot help. It becomes very important then that the selected features work amazingly well!