Category Archives: Gadgets & Toys

Regenerative amplification

When I take my foot off the accelerator in my electric car, the ‘regenerative braking’ process charges up the battery. Similarly if I’m going downhill. This is reasonably well-known now.

Well, I was talking to a friend today about his planned purchase of some high-tech hearing aids. They sound splendid, though they should do for the price. It would be cheaper to put two MacBook Pros in your ears… though perhaps a bit less comfortable.

Anyway, I was asking him about their battery life, and, pondering this topic later, I was thinking that you ought to be able to do something similarly clever there: if they use power to amplify things which are too quiet, could they also recharge their batteries by deadening things that are too loud? If you were out for a long day and they started to run down, you could simply head for a loud rock concert, or perhaps seek out a high-crime area and stand near some police sirens. Even if the recharging didn’t work very well, you wouldn’t be able to hear anything afterwards anyway, so you wouldn’t care.

Brilliant, eh? I’m off to the patent office…

A top-down view

My friend Richard has done a lovely blog post showing some of his recent experiments with a spherical (‘360-degree’) camera. (Hint – you may need to pick your browser to make all of these work well, and the YouTube videos are best viewed in the YouTube app on a mobile device. Try dragging the view around with your mouse/finger.)

One clip that I particularly liked was this one, from the top of a punt pole.

Now, I had played with this new art of punt-pole photography some time ago, as a way of getting shots that would otherwise be tricky. (Remember, this was back in the days when, if you talked about drones, you were probably referring to bees.) And I’ve since played quite a bit with a spherical camera.

But I hadn’t thought of combining the two. Which is why it always pays to have friends who are smarter than you are…

The 360 camera I used for a while was on loan from the Computer Lab, and I’ve since returned it. But Richard’s post is definitely making me miss it… I may need to get another…

A well-rounded view

Over lunch yesterday, my friend Richard was expanding my limited knowledge of spherical cameras: cameras which can take an all-round image – or even video – of the world; an immersive view which you can then explore in a VR headset, or by holding up your phone and moving it around, or (suboptimally) in a regular browser window by dragging around with your mouse, StreetView-style.

Richard’s done a nice blog post about this, from which I’m shamelessly cribbing! Thanks, Richard!

The normal way to get high-resolution all-round footage is to use a special rig like this one:

These are actually not that expensive… assuming that you already have ten GoPro cameras lying around ready to go in them. If not… it’s a different story.

But there are now more compact and affordable options if you don’t mind sacrificing some resolution – things like the Ricoh Theta V. For more information about how it works, Richard pointed me at this great video:

Now, we all know that you can get interesting feedback effects when, say, standing in a lift or changing room with mirrors on opposite walls, or by pointing live cameras at their own output.

What happens when you explore the same ideas in a spherical world? Cool things:

Oh, and if you’re like me, the next question is, “Can you do this kind of thing with live footage?” And the answer is yes. Here’s… ahem… a recording… to prove it…

A final thought.

In the old days, some comedy shows would emphasise that they were “recorded in front of a live audience”, so that you knew that the laugh track wasn’t canned. Soon, we’ll be able to recreate the effect of a live audience so realistically that it won’t be sufficient to persuade you that the recording was actually done in front of real people. Even if you have multiple spherical recordings.

So here’s a challenge to ponder over the weekend: How could you prove that a YouTube video of an event was originally a real event, shown to real people?

Future Imperfect

As someone who has watched a few Star Trek episodes recently… well, OK, I admit it… a few dozen Star Trek episodes recently, I must express my concern about the quality of hardware engineers employed in the construction of Federation starships.

Why is it, that after several generations, they still build ships with computer consoles that explode at the slightest hint of enemy phaser fire? Perhaps Samsung had a watertight long-term supplier contract and the Federation couldn’t get out of it, but still, it does seem like a serious design flaw, especially on the bridge.

If you search the web, of course, you’ll find that I’m not the only person to have noticed this, indeed, there are many long discussions which might provide an answer if you’re a bit more interested than I was. If you’re considering a career as a Starfleet officer, however, it might be worth your while doing some more extensive research.

Perhaps the consoles are more robust than they might appear, though. Others have pointed out that a surprising number of them do seem to keep working after having exploded.

So the basic underlying manufacturing is sound. Like so many computer consoles, though, more work is needed to improve the user experience.

Zooming in the rain

On Wednesdays, there’s an interesting group of catering vans that collect at the far end of the West Cambridge campus, and I like to go there for lunch.

But it’s a bit of a distance, and the weather today was bad, so it was important to find the most appropriate method of transportation…

A possible solution to slow or unresponsive Hue lights

They used to say that there are two ‘internet of things’ systems that ‘just work’ out of the box: the Sonos sound system, and Philips Hue lighting. I’m fortunate enough to own both of them, and I would add the Honeywell Evohome heating system (though one of my friends has had a few complications with an unusually large installation).

When we moved house recently, though, my previously-faultless Hue system seemed to become a bit less reliable. Admittedly, we have rather more bulbs now (33 and counting), but that’s nowhere close to the limit it can handle. Our bulbs are always powered, so the cunning mesh networking should make sure that nothing is out of signal range. Yet sometimes lights weren’t obeying their commands promptly, switch presses needed to be repeated, and things generally seemed, well, a bit sluggish. I was beginning to think it might be time to wipe the configuration off my bridge and start again from scratch. It probably does have a lot of accumulated junk on there…

And then I did a little research and realised something that I should have thought about earlier.

Zigbee (the wireless networking used by Hue and a variety of other systems) runs at approx 2.4Ghz: the same frequency range as Wifi. Like Wifi, it has a number of channels, and if your wifi router and your Zigbee hub have overlapping channels, they can interfere with each other. I found this useful diagram online (apologies for not knowing its creator):

‘802.11b/g’, in case you don’t know it, is part of the technical standard popularly known as Wifi, so the green labels show Wifi channels, and the blue bars show Zigbee.

The number and availability of channels vary depending on your country, but they will be similar to the above. Although Wifi has about a dozen channels, the nearby ones overlap substantially, so most installations only use 1, 6 or 11: if both you and your neighbour are using Wifi channel 1, you won’t make much difference by switching to 2 or 3; you need to go at least as far as 6. Go much further than 6, and you’ll start interfering with your other neighbour on channel 11. Usually, these days, wifi routers are pretty good at picking their channel by finding the least congested space, though you may need to reboot them from time to time to encourage them to do so.

Anyway, one thing that had changed in my new house was the Wifi. And when I looked, sure enough, my Wifi router was on channel 11 and my Hue hub was on a Zigbee channel that was rather too close for comfort. By going into the Hue app and looking at the settings for my Bridge, I was able to change the Zigbee channel to number 15, and things are going a lot more swimmingly now!

Hope that might help someone else…

Update: As Nigel points out in the comments, if you have 5GHz wifi available, moving as many of your devices as possible to that will also help!

iOS tip of the day

When you’re setting up your fingerprints for Touch ID, take the time after registering each one to go in and give it a name. Then if you find one finger becoming unreliable, you know which one to delete and reprogram.

© Copyright Quentin Stafford-Fraser