Machine Access Node

Hackspace has machines, that ideally need to be inducted and access controls for safety reasons. A vital step towards the goal of 24/7 access on membership. A bonus of the system would be usage tracking and maintenance notifications.

A solution is a control device consisting of a box which enables the machine for as long as your RFID card is in the box. A Tool Access Node.

Potential design

• Esp8266
• 3A Relay
• bi colour LED
• Card interface header
• DPI switch addressable (or other)

Functional Specs

Mission Critical

These must work without networking or the main server being avalable.

• Check if card valid in local storage
• Set tool into "out of order" mode - must work without networking

Functions

• Relay contacts of at least 10 amps for switching the device. Hard-wired in using suitable grommets and with sufficient isolation between low and high voltage.
• Internal database of (up to at least 200*) authorised RFID card IDs, plus a flexible way of fetching updates from a membership server.
• Logging of who used the machine + hours used.
• Open Source hardware & software.
• Status light, for "active", "denied" and "thinking". (Although "active" is really the only important one, and blinking is fine)

"Nice-to-haves"

• Ideally sub-£30.
• Mains Powered
• Ability for super-users to program new cards from the device - this should result in a callback to a membership server to verify it.
• Easy to program/modify
• Ability to monitor "actual" hours run - i.e. how long the laser cutter tube is actually on for. (This could potentially be done using a current transformer sensor.)
• Ability to poll for current state over the network.
• Broadcast events on the network.
• Ability to update the software over the network.
• Relay / Darlington / Servo output configurations.