View source for How to Connect to the Physical World

{{External Programs}}
Scratch [[project]]s can be '''connected to the physical world''' using several different kinds of devices. Some are:
# Makey Makey
# [[LEGO Education WeDo Robotics Kit|LEGO WeDo Kit]]
# [[LEGO BOOST Extension|LEGO BOOST]]
# [[EV3|LEGO MINDSTORMS EV3]]
# [[Go Direct Force & Acceleration Extension|Go Direct Force & Acceleration sensor]]
# [http://scratch.saorog.com Kinect2Scratch], using Microsoft Kinect
# GrovePi for Raspberry Pi
Each of these work with [[Scratch 1.4]]. MaKey MaKey and several other devices can connect to [[Scratch 3.0]] by [[Scratch Extension|extensions]].

==Makey Makey==
{{main|Makey Makey}}
[[File:MaKey MaKey Circuit.png|thumb|350px]]

[[File:makey line drawing.jpg|thumb|350px]]

Makey Makey allows people to turn everyday objects into keys and use them with their computer.

* Makey Makey works by opening and closing circuits, using the user's body and other objects as conductors. It uses very little electricity, so it is safe, and it won't be felt
* If two alligator clips are attached to the Makey Makey board, an apple and the user's body, then,  when the user touches the apple, the circuit is completed (closed) and the computer recognizes this as a key being pressed. The Makey Makey uses standard "USB input device" drivers, so the computer thinks Makey Makey is a regular keyboard or mouse even though a unique key has been made.

The default keys are the arrow keys, the space bar, and left click. They can be remapped using the website.
Example use of Makey Makey:
* To make Makey Makey work with Scratch, plug in the USB to a computer and create a Scratch program normally. For example, when the right arrow key is pressed, the sprite moves 10 steps.
* Then, connect one of the alligator clips to Earth at the bottom of the Makey Makey board and touch the metal at the other end of the alligator clip with a finger.
* Next, connect another alligator clip to the apple and the right arrow on the Makey Makey board.
* When the metal clip and the apple are touched at the same time, the circuit is completed and the Makey Makey sends a signal to the computer saying a key is pressed. Every time the apple is touched, the sprite will now move 10 steps.

An alternative to using the steps above is by using the [[Makey Makey Extension]].

To purchase a Makey Makey, visit [http://joylabz.myshopify.com/products/makey-makey-kit Makey Makey's website].

For information on how to set-up a Makey Makey, visit [http://makeymakey.com/howto.php Makey Makey Set-Up].

For information on different materials to use with Makey Makey, visit [http://makeymakey.com/howto.php#materials Makey Makey Materials].

For information on troubleshooting Makey Makey, visit [http://makeymakey.com/howto.php#troubleshooting Makey Makey Troubleshooting].

Article on ideas of uses for Makey Makey, [http://make-digital.com/make/vol33?pg=58#pg58 Makey Makey Article].

<!-- Building a ShrimpKey is a much cheaper alternative to buying a Makey Makey: [http://scratch.mit.edu/discuss/topic/13757 source] -->

==LEGO WeDo==
[[File:LEGO WeDo.jpg|thumb|350px]]

{{main|LEGO WeDo Construction Set}}
The LEGO WeDo kit can be used to make motors and sensors interact with Scratch projects. It has a distance sensor, a tilt sensor, and a motor.

Example uses of the WeDo parts:
* Making a machine move when the distance sensor detects a certain distance.
* Wave a hand to change the size of a sprite when the distance sensor detects a certain distance.
* Using the motor to spin attached objects.
* Using the distance sensor to control the speed of the motor.
To find out more about LEGO WeDo parts and how you can use them in Scratch, LEGO Education WeDo Robotics Kit.

To purchase LEGO WeDo, visit the [http://legoeducation.us/eng/product/lego_education_wedo_robotics_construction_set/2096 LEGO Education Website].

==PicoBoard==
{{obsolete feature|cat=no}}{{main|PicoBoard}}
[[File:PicoBoard Diagram.png|thumb|400px]]
The PicoBoard provides a way for you to make Scratch projects sense and respond to events/objects  in the world outside of the computer.

Examples of use with the PicoBoard:
* Use the sound sensor to make your sprite change how it looks whenever there is a loud sound.
* Use the light sensor to program a sprite to hop up or down whenever a shadow passes by.
* Use the slider and button to control a character in a video game.
* Use the USB cable and four sets of alligator clips that come with the PicoBoard to measure an electrical resistance in a circuit. The alligator clips can be used to build all kinds of custom sensors.

For more ideas on what to make visit the [http://picocricket.com/picoboard.html PicoBoard website].

To get started using the PicoBoard visit the [http://picocricket.com/pdfs/Getting_Started_With_PicoBoards.pdf PicoBoard Getting Started Guide].

To purchase a PicoBoard visit the [https://sparkfun.com/products/10311 SparkFun website].

If you own a ScratchBoard, a product similar to a PicoBoard that was sold through the Scratch website, the support information you'll find at the [http://picocricket.com/picoboard.html PicoBoard's website] is applicable to your product as well.

If you own a ScratchBoard or PicoBoard and want to know about sensors that you can connect to it, look at the Sensor Types and Sources below.

===Sensor Types and Sources===
The following list shows different types of sensors that have been used in Scratch Sensor Board projects. (They are typically attached to alligator clip-heads plugged into sensor board jacks A, B, C, or D.) Visit the vendor site for pricing and ordering information.

Name; Description; Vendor Part Number
* '''Switch'''; Switch lever spdt 3A PCB; http://digikey.com SW773-ND.
* '''Temperature'''; Thermisor NTC 10K OHM 5%; http://digikey.com 317-1258-ND.
* '''Light'''; Photocell 5K-20K OHM 4.20 MM; http://digikey.com PDV-P9203-ND.
* '''Magnetic switch - 1'''; Switch Reed 10-15AT SPST .5A; http://digikey.com 420-1047-ND.
* '''Magnetic switch - 2'''; Switch Reed SPST .5A 12-23 A/T; http://digikey.com HE502-ND.
* '''Humidity'''; Consists of a metal electrode on a humidity sensitive membrane mounted on a ceramic substrate; http://rhopointcomponents.com  SYH-1NC.

<!-- Thanks to Claudia Urrea for the initial list. -->

{{note|When using resistive sensors with the XO microphone port, it appears that the interesting resistance range goes from around 2k to 5k. (Experimentally determined; the user's mileage may vary.)}}

== LEGO BOOST ==
You can use the [[LEGO BOOST Extension]].

== LEGO MINDSTORMS EV3 ==
You can use the [[LEGO MINDSTORMS EV3 Extension]].

== Go Direct Force & Acceleration ==
You can use the [[Go Direct Force & Acceleration Extension]].

==Kinect2Scratch==
[[File:Kinect2Scratch1.png|thumb|250px]]
Kinect2Scratch works by using the sensor recognition in Scratch and the Microsoft Kinect. The Microsoft Kinect works by recognizing certain bone movements in the human body, such as waving an arm, and Kinect2Scratch has created the software to have Scratch recognize this as well.

To download the Kinect2Scratch software, visit [http://scratch.saorog.com Kinect2Scratch's Website].

For the set-up guide on how to install and use Kinect2Scratch, visit [http://scratch.saorog.com/setup.pdf Kinect2Scratch's Set-Up Guide].

For ideas on what to do with Kinect2Scratch and sample projects, visit [http://scratch.saorog.com/samples.html Kinect2Scratch's Examples].

==GrovePi for Raspberry Pi==

[[File:DexterInd GrovePi-Base-Kit.jpg|250px|right|Dexter Industries GrovePi Kit]]The '''Dexter Industries GrovePi''' is an Internet of Things (IoT) device built on the Raspberry Pi. The GrovePi can be programmed using the native Scratch installed on the Raspberry Pi (Scratch 1.4 or NuScratch). Programs that read plug-and-play sensors, and control everyday devices can be written.

The GrovePi can be used with the Raspberry Pi Models A, A+, B, B+, 2 and 3.

==See Also==
* [[LEGO Education WeDo Robotics Kit]]
* [[PicoBoard]]
* [[Connecting to the Physical World (forum)]]

[[Category:Scratch Connections Tutorials]]

[[nl:Scratch voor makers]][[de:Scratch mit Hardware verbinden]]