Pre-Flight Briefing ANSR-79

Pima Community College3/28/14

• Nick Patzke

• Gustavo Guerreo

• Nick Morris

Team Members

Why can’t we successfully fly a GoPro camera through space in

a “naked” state?

Payload Motivation• Payloads used in ANSR balloon flights are subjected to temperatures as

low -60 C which usually require additional heating and insulation.

• This results in limited mounting configurations, additional weight and take up space better served for circuit boards, etc.

• Most ANSR payloads have some form of camera (still or video), that generally require special attention.

• Most payload camera failures are the result of battery “failure” at extreme temperatures.

• GoPro technical staff have no data on their cameras and their behavior at low temperatures.

• The goal for this flight is to examine GoPro camera behavior during an ANSR flight.

Payload Objectives

• Build a simple payload holding two GoPro cameras aimed at answering questions about their usability in extreme conditions.

Lamp-rod Configuration:

• One GoPro with OEM battery as a control ‘group.’

• Another GoPro powered by a larger capacity and voltage battery.

(LiPo 11.1v 3S 2250 mAh)

GoPro 2

GoPro 3

5V Regulator

GoPro Issues In SpaceThe Battery

• Li-Ion batteries shipped with GoPro cameras today are specified to have a minimum operating temperature of -40 C

• For most applications, this limit is far lower than the camera or battery will ever experience.

• But we want to send them into near space and back…(min expected temp ~-60C)

But Why Can’t a Battery Operate at < -40C ?

• A batteries’ internal resistance increases as temperature decreases:

• As internal resistance increases, load voltage decreases:

• As load voltage decreases, available current decreases:

• At some point (due to the cold) the available current should decrease past the necessary 0.5A needed and the camera will shut off.

• Or the remote possibility of a defective battery…

Payload Structure

Battery Testing

Test Box Lab

AcknowledgementsSpecial thanks to the following for offering this opportunity!:

Jack Crabtree and ANSR

Susan Brew and NASA Space Grant

Mike Sampogna

Dr. Denise Meeks