(Ollie) Do you know someone who has a sixth sense?
Well that’s a trick question, because technically everybody does.
I’m Ollie, from CSIRO.
And you actually have more than the most well known
five senses, sight, hearing, touch, smell and taste.
In fact you have many more senses which you use all the time,
probably without even realising.
For instance, there’s proprioception,
the ability to sense the position of your body parts
in three dimensional space;
Then there’s temparecption,
which allows you to sense the passage of time;
Also there’s thermoception,
which can help you sense changes in temperature;
As well as many others.
But let’s look at equilibrioception,
that’s your sense of balance,
and one of the main places where this happens in your body
is the vestibular system in your inner ear.
This consists of three semicircular canals
oriented in different positions
to allow you to sense the position of your head in three dimensions.
There’s also this bit called the utricle,
a tiny organ only a couple of millimetres wide,
which allows you to sense changes in your body’s velocity.
In a way it acts sort of like an accelerometer.
So now let’s take a look at how you
can build your very own accelerometer.
(Vanessa) So making an accelerometer is pretty easy.
As you can see I don’t have many things here
and the main thing you’re going to use is this cork.
Now we’re going to put this rubber band around it,
but before we do that, it’s a little bit fiddly,
but it works best if you tie a few knots in the rubber band.
So one pretty close to one of the ends
like that.
And another one about halfway along
the rubber band that you have left there.
So
just like that.
Now what you’re going to do with
the big bit at one of the ends is to put that around the cork.
Now I’ve put a couple of grooves just in the top of our cork.
So it sits in there really well,
so you can do that with a pair of scissors.
And if we stretch it around,
it’s a good idea to kind of fix it down with a bit of tape,
so the rubber band doesn’t come off.
There we go. Maybe another one for good luck.
Cool.
So that’s the main part of your accelerometer.
It’s really easy after this,
all you need to do is to take that top bit of the elastic,
so the knot as well onto the lid just here.
So quickly do that,
and then you’re pretty much done.
Cool. I’m going to put some tape on the edges
because I kind of touched that tape all over,
and expect it to come off pretty quickly.
So just fix it down
kind of like that.
And your accelerometer should just be looking like this.
Now all you to do
is to fill up your jar with water,
so
almost all the way to the top.
There you go.
And
once you’ve screwed the lid on
make sure you screw it on nice and tight
because we have to flip the jar over.
And you don’t want it to fall out everywhere.
Cool.
I could probably have put a bit more water in here,
so I’ll fix that up in a second, but
we’re ready to measure acceleration.
We decided that walking was a little boring,
so we got this Segway to use our accelerometer.
[Music plays]
So the cork wasn’t really moving,
because it only responds to large accelerations,
like if I move it really fast like that.
You’ll probably notice that the cork goes right to one side of the jar
Write in the comments why you think that’s happening.