The Official Raspberry Pi Projects Book - Projects_Book_v4

Review

raspberrypi.org/magpi The Official Raspberry Pi Projects Book 179

Let your

Raspberry Pi

and camera

look at

the world

around you

Pimoroni

Maker

Says

PAN-TILT H AT

he Raspberry Pi Camera

Module is one of the best

accessories you can get,

enabling cheap photography on the

Pi. But it doesn’t sit upright on its

own – a stand is required.

The Pan-Tilt HAT fulfils this

function and a whole lot more.

The Camera Module is mounted

on the end of a robotic arm that

sits on top of the HAT. Thanks

to the arm’s horizontal and

vertical joints, the camera can

be angled precisely by the two

servo motors.

The finished effect is adorably

cute, instantly imbuing your

Raspberry Pi with personality

as it looks around the room.

It’s really useful too. You

could set the Pan-Tilt HAT up

to monitor a room, and then

use VNC or SSH to adjust its

viewing position remotely.

Alternatively, you can set up a

Raspberry Pi with face-tracking

software and connect it to the

Pan-Tilt HAT. Pimoroni, the HAT’s

makers, also suggest mounting it

on top of a robot for a set of eyes.

Setting it up

First, you need to set the HAT up.

Fortunately, there is an online

setup guide (magpi.cc/2hR4NFC).

The board has a GPIO connection

on one side, and servo connections

on the other. The two sets of cables

on the arm are connected to Servo 1

and Servo 2 on the board (1 for pan,

2 for tilt). A third servo channel

can be used to control an optional

NeoPixel strip for lighting.

Camera control

You can download all of the code

from Pimoroni’s GitHub page

(magpi.cc/2hRrjyo). You need to

install the pantilthat module to

access the controls.

After importing the pantilthat

library in Python, you use pan()

and tilt() methods to change the

camera position. These accept any

value between -90 and 90. To set

the camera straight forward, for

example, you would use:

pantilthat.pan(0)

pantilthat.tilt(0)

To look up by 45 degrees, use:

pantilthat.tilt(-45)

To look all the way to the

camera’s left, you’d put:

pantilthat.pan(90)

We would have dearly loved more

software examples. There are ones

for motion and NeoPixels, but none

for recording from the camera or

face-tracking. A few more sample

programs and it’d be perfect.

Even so, we had a lot of fun

setting up the Pan-Tilt HAT and

look forward to researching and

coding a face-tracking program.

Raspberry Pi camera stand with horizontal and vertical motion servos

T

RASPBERRY

PI CAMERA

MOUNT

It doesn’t move,

but if all you’re

after is a camera

mount, you can

pick one up

from The Pi Hut

for a tenth of

the price.

magpi.cc/2hRtkdT

Related

£3 / $4

PAN-TILT HAT

magpi.cc/raRzbi

£30 / $33

Last word

A highly enjoyable and

extremely cute accessory.

With a bit of research, you

should be able to create

some fun things with it.