2017-09-15 EMF 2018 Collaboration Meeting

Where / when: Nottinghack, studio; 2017-09-15 (Fri), 19:15 ish

Attendees: Ian D, Matt L, Daniel S, Mouse.

Proceedings

Sensors =

The obvious choices are optical: infra red or visible lasers.

The signal can/should be modulated somehow to send a little bit of data
- Could just be some way to ensure light comes from a gun rather than some other light source
- Could also include some unique ID for a specific gun, so targets may know who shot them
How do IR sensors respond to daylight? The targets will be in a marquee, but there may well be daylight flooding in, and they will be facing to the door / open section
We could try to get hold of some sort of Quasar-like system, or find an open source Quasar-like project to work from. For sure this already a solved problem

Possible target effects

Squirting water
Air vortex
Bubble machine
Smoke machine
Bell / clang
Tin can alley
Chicken house
Nerf gun (how to reload?)
Rumble / vibration
Spinning things
Play audio
Projector / game, e.g. Tetris
Jacob's ladder
Smoke machine?

Networked vs. standalone targets

Networking targets with RS485/HC12/other technology, pros:

Can have more sophisticated play
Can have per-player scores
Central brainbox can do things like tweeting etc, while keeping targets simple / cheap
Would want string isolation of target logic and effects (i.e. motors and other loads should be self-powered and create minimal noise on serial bus)

Beginnings of as basic target board

optical sensor
low-cost micro controller
place for relay
RS485 connection

When hit, these basic target boards would do some standardised action, like trigger the relay for 1 second. The isolated side of the relay would be connected to whatever mechanism the maker of the target needs to create an effect.

Case-study effects

We talked through how some effects might be implemented to see if that would fit with the basic target board concept...

Spinning tea-pot

basic target board connected to effect by relay
effect would have microcontroller + motor driver + motor + the physical teapot
relay would connect a pulled-up data pin to ground
arduino controls motor to spin teapot
triggering would be limited to one trigger per second or however long the target board takes to reset
arduino code would have to be able to re-trigger half way though performing the effect, and handle this gracefully

Water shooter =

Thinking through how to implement the classic hillbilly rifle shooter

When hit, turns manikin towards shooters, squirts water at them, turns back
Might want to know WHICH gun shot it - would need to get ID of gun from RS485, so can't just be connected to relay
Could put it on the RS485 bus, listening for events from the right target and extracting gun ID from traffic

Tetris =

Projector / large screen with Tetris
Four targets perform spin and move operations
Would probably be implemented with an RPi
GPIO inputs from four separate relays, or could monitor RS485 traffic

Sequences =

Special combos might trigger extra effects (e.g. setting off a sub-set of the targets simultaneously)
Would require targets to be able to be triggered from central brainbox (i.e. over RS485)
Maybe all targets should be triggered from RS485