Quando - Visual Programming for Digital Interactive Exhibits

What is Quando?

Quando looks similar to the Scratch 'block' editor often used for learning to program, or for end user development.

However, Quando does not use standard programming concepts and does not expect users to learn to program and is aimed at End User Development.

Who is Quando for?

Quando is aimed at end users and domain experts wishing to create and edit digital interactions without having to become programmers.

What can Quando do?

The main benefits of Quando are:

• Very quick creation of simple (i.e. not deep, but typically shallow) interactions
• Exploring different interaction options and choosing between different options quickly
• Discovering different ways to interact and learning about different inputs and outputs and how they work for (other) users

What types of inputs are available?

Quando allows many different inputs (and more are being added), including:

• browser client including buttons
• Leap Motion hand movement in 3 dimensions and rotation in 3 'angles' (six degrees of freedom)
• Mouse and Keyboard
• micro:bit keys, orientation and (version 2 only) touch
• Gamepad input (browser or local PC)
• (experimental) EEG headset
• (experimental) speech recognition

What types of output are available?

Some of these outputs also include inputs:

• digital media - images, video, audio and (experimental) sound waves
• (in progess) 3d object/scene
• (experimental) Augmented Reality
• Speech
• Control of (local PC) mouse and keyboard
• (experimental) Nao Robot control including full movement, speech, etc.
• microbit + rp2040/pico servo control and esp32 (display)

What can Quando be used for?

Quando has been used for:

• remote control of applications and games
• interactive exhibits for museums, typically using the touchless Leap motion controller to interact with information displays
• touchless interactive control of robots to aid understanding of robot abilites

Why is it called Quando?

The name Quando comes from Latin for 'when' since Quando use a When based approach to describing behaviour rather than an if based approach.

Installing Quando

Quando can currently be installed:

• On PC (windows tested) as a local server - please see these instructions. You should only need to do this once.
• (NYI) Cloud - this installation will not include local PC control keyboard/mouse, or access to connected (USB) devices.

Running Quando

To run Quando locally, follow these instructions

Building Quando as a separate executable

Quando can be built for three different deployments:

1. (typical) local - which includes access to USB devices and typically runs on a PC
2. full - the same as local but also including control of mouse and keyboard which may be UNSAFE. See also below re. running Quando
3. cloud - without either the above tags - this build does not access any local devices/keyboard/mouse

Runtime options for remote access

At the command line, there is one option that allows remote access:

• -remote
  • allows editing and running scripts from other machines - e.g. by scanning the QR Codes shown at http://127.0.0.1
  • N.B. if quando has been built with 'full', then this is UNSAFE since scripts can control the PCs keyboard/mouse

Otherwise, the client and editor are only available to the local, i.e. local PC, browser

Using the Quando:Editor

You can open the Editor from the dashboard at 127.0.0.1 or by opening 127.0.0.1/editor in Chrome browser.

Using the Quando:Client

After you have deployed scripts, you can open them from the dashboard at 127.0.0.1 or through 127.0.0.1/client in Chrome browser, which will load the last script that was opened. You can Ctrl right click the screen to choose a different script to load.

Updating Quando

Assuming you installed correctly, you can update quando, in a command line, in C:\quando, using:

git pull

Optional - Leap Motion

To use the Leap Motion, an older version of the Windows software v4.1.0+52211 must be installed on a PC (likely windows only)

• i.e. where the leap motion will be plugged in and the client interaction will be opened (in a web browser)
• The software may be downloaded from here.
  • Note: this will download a zip and also open the newer software page - which you should ignore.
• You will need to extract the zip contents
• then run the 'Leap_Motion_Installer...' - you can uncheck 'Launch Browser for VR Setup'.

After installing the Leap Motion Control Panel, the recommended settings are:

• Enable in General - disable everything else
  • Allow Web Apps ESSENTIAL
  • Robust Mode
  • Auto-orient Tracking
  • DISABLE Automatically Install Updates
• Enable in Troubleshooting
  • Low Resource Mode
  • Avoid Poor Performance

Then plug in the Leap Motion and test it with the Diagnostic Visualizer - this can help identify lighting issues as well.

Client browser Kiosk setup - allows PC to boot straight into client browser interaction

Follow these instructions

Developing new Blocks

You should install Quando locally to develop new blocks.