posted by Bryon Moyer
A little over a year ago I went on a bit of a rant about intuitive design. Now… for those of you running for the door, I’m not going to reprise that rant. At least, not directly. But a comment at the recent Touch Gesture Motion conference got me thinking (always a dangerous thing), and from it came a new corollary conclusion.
The speaker noted that today’s phones were so intuitive that his 18-month-old could use them, and, in fact, that was a problem in case the child dialed Europe in the middle of the night. We all chuckled; cute.
But then I thought, “That’s not intuitive.” If that were really intuitive, then that means the 18-month old is waking up in the middle of the night going, “OK, cool: Dad’s asleep now. I can make that call to Europe I’ve been wanting to do. Let’s see, how would I do that? Let me try… this. Ah! Success!”
In other words, intuition suggests having intent and then knowing without learning how to achieve the goal. That’s not what the 18-month old is doing.
As I suggested in the prior piece, a baby is in super-learning mode. They try everything – touch, swipe, taste, smell, bang, drop – and watch what happens, duly filing away the results. Yes, they need lots of repetitions to convince themselves that, for exampl, gravity does indeed work every time (as any parent who has tried to keep the toys or dinner off the floor can attest). They have no idea what they’re doing in many cases: they just try something and see what happens.
They also do try to swipe and touch screens and such. Why? Because they see us do that. So they’re not undertaking intuitive actions; they’re learning how things work – the opposite of intuition. And I kind of drew this conclusion in the earlier piece.
But then it occurred to me: if you really want to test out intuitive, babies are NOT the right model. If you can give your grandparents a new device and he or she can immediately figure out how to use it, then you’ve got something intuitive. Unlike the baby, they don’t want to have to learn some new way of doing things; they just want it to work.
My guess would be that, by that standard, there are precious few intuitive interfaces. Because how many grandparents have been able to get going without asking for help from the grandkids?
(Yes, I know, this notion – however rational – will be, if even noticed, duly ignored by the rush to keep convincing ourselves that we have intuitive stuff. Ah groupthink…)
posted by Bryon Moyer
We now have a new category in the IMU world: Bosch Sensortec has announced the first of what they call Application-Specific Sensor Nodes, or ASSNs. They have dubbed this particular device an Absolute Orientation Sensor. It looks strikingly like an all-in-one sensor hub, with an accelerometer, a gyro, a magnetometer, and a 32-bit ARM-based microcontroller (source not disclosed).
The difference is that a sensor hub per se leaves the software to be executed on the micro pretty wide open for the user to define. The BNO055, by contrast, is really intended to combine the motion sensors via built-in fusion on the micro so that it looks like a higher-level orientation sensor. It essentially bumps up the level of abstraction, burying the sensors and micro inside something more akin to a black box. Data is communicated pre-computed as quaternions rather than raw.
Power is addressed by allowing a stand-by mode where the gyroscope – always the power hog – can be put to sleep. When the accelerometer detects motion, it can then wake the gyro – which responds in a few nanoseconds – so that it can intercept any rotational motion. This assumes, of course, that any rotation missed during that wake-up is negligible. (Quick math sanity check says that if an object rotates, say, 6 degrees in 10 ns, then that’s 60 degrees in 100 ns or a full rotation in 600 ns… divide by 10 to get 60 ns, multiply by a billion to get 60 s, so that would be 100,000,000 RPM… yeah, not even Washington DC can spin anything that fast…)
So full power is around 11 or 12 mA; in motion-wakeable stand-by it goes down to 150 µA. If you put everything to sleep and wake it through I2C instead, you can get down to the 20-µA range.
You can find more on this device in their release…
posted by Bryon Moyer
Flash memories degrade over time as the oxide gets damaged and loses its ability to hold charge. It’s apparently well known that this damage can be annealed out, but that takes time and/or temperature. You can’t heat the chip over 400 °C, so you have to anneal for minutes for nominal results.
As described in an IEDM paper, Macronix modified their cell to allow a high current in the vicinity of the cell. By running that current for milliseconds, it could create local heating above 800 °C. This resulted in endurance over 100,000,000 cycles with good retention.
Alongside the MRAM papers, it strikes me as a familiar thing because Crocus also uses a local heater for thermally-assisted switching of their MRAM cells, although the temperatures aren’t nearly as high. I don’t know if this is truly a case of cross-pollination, but it feels like it.
If you have the IEDM proceedings, more detail is available in paper #9.1.