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Modified from I.Cerda Thesis: To chronically track food and water consumption and preference, nose-pokes must be detected at the four water or food dispensing ports located inside the mouse cage. To that end, our system employs four Beambreak Assemblies, one at each dispensing port, comprised of an optical switch photointerruptor relying on infrared light (Mouser Electronics), a male 3-pin connector that interfaces with the female connectors of the Motor Shield Assembly, and a 220 Ω current-limiter resistor to protect the infrared LED. When the mouse introduces its nose in one of the ports fitted with the photointerruptor, the assembly generates a digital output signal that is picked up by the Motor Shield Assembly and it triggers the corresponding dispensing action as outlined in the Arduino-Motor Shield Construct section.

Name: Port Beambreak Assembly

Shortname: Port Beambreak

Subcomponents:

• Optical Switch
• Photo Interrupter Breakout Board

Connectors:

• "PWR" Red wire, 5V Power
• "GND" Green wire, GND
• "SIG" White wire, Signal

Description: A complete beambreak assembly to detect nosepokes in one of the ports. Connects to the Motorshield Assembly via the Male 3-Pin Connector.

Optical Switch

Optical Switch Optical Switch Image

Name: Optical Switch

Shortname: Optical Switch

Part #: .852-GP1A57HRJ00F?

Ordering Link

Description: A black optical switch photointerruptor that's used for detecting mouse nosepokes at the ports.

Photo Interrupter Breakout Board

Photo Interrupter Breakout Board

Shortname: Photo Interrupter Breakout Board

Part #: .474-BOB-09322

Ordering Link

Description: Used to attach the Optical Switch to the 220 Ohm resistor and finally to the Male 3-Pin Connector.