BOB SOS: Back off bear alert – Jeannette, Hugh

Context: First, a report that a young boy was lacerated by a bear in a forest near us and a suggestion that we build a bear detector. A week before, JY learned how to solder and program an arduino to make an LED blink like one of the firefly species. A day before, she got 2 servo motors to shake a noisy shiny piece of mylar. We took these starting points from the lab into the forest: NFCCDL: North Fork Citico Creek Digital Lab.

bear bagbear bag is placed away from camp


Marketability: In the forest, product took a practical side, shifting from an alert of mere presence of a bear to a lightweight, compact attachment to a camp tent to alert the camper.

Capability: Need to see all around so need to figure out how to station the system on the peak of tent to expand the perceptive field. There is no need to know direction, only presence.

Interaction with nature: design an output that would scare a bear.


close up


Detect the presence of a bear near the tent.

Wake up camper inside tent.

Simultaneously, start up a set of blinking lights in shape of eyes separated by a distance to signify a large size that could scare a bear.

BOB input input: sensing system 4 motion detectors

BOB outputoutput: LED to scare bear and buzzer to wake camper in tent


Input: 4 Motion detectors, range of 20 ‘ and 90 degree cone of detection.

Control system: Arduino, breadboard, battery pack

Output: LEDs, buzzer



Make a 3D attachment site for sensing system: a magnolia bud that smells like oregano.

Make platform for control system: a flat piece of oak bark

Get output to appropriate locations: long lead for buzzer to inside tent, 2 leads to scary LED eyes sewn onto a fabric with face-like decorations to hide wiring.

Programming a scary message to a bear: flash out SOS in morse code on LEDs and wake up camper with a buzzer using same program.

Attachment to tent: used set of strong magnets

close up BOB SOS in place on hammock tent tarp



Incident: unaware of a bear attractant still remaining within the tent

Bear approaches and is detected.

Camper is alerted and bear is scared off by illumination system.


2nd prototype:

Simplify attachment to tent.

Test whether bears are scared by flashing lights that look like eyes of something bigger than themselves.