High Altitude Balloon Data Logger for Scientific Payloads

Presented by: Dallas Hodge

Spring 2014

2014 Space Grant Symposium

1

Outline

• Background motivation• Conceptual design• Detail design elements• Implementation• Flight results• Ultimate outcome

Background

• Embry-Riddle supports the Arizona Near Space Research (ANSR) organization

• Student teams routinely launch

experimental payloads

into near space

• Typical altitude

of 100,000 feet above sea

level

3

Background Continued

4

Pop

Balloon burst

Parachute descent Slow ascent

Fill balloon and launch

Recovery

1

2

3

4

5

Project Motivation

Need expressed for a simple kit or pre-assembled data logger which accomplishes:• Electrical/computer engineering summer camp 2013

• Introduction to applied electronics

• Simple sensor instrumentation exposure

• Reliably collect and save data to a removable memory element

5

Conceptual Design

Composed of microcontroller with input signal conditioning and data storage to an SD card

6

Preliminary Design

• Atmega328 microcontroller and Arduino development environment selected.

• Difference op-amp for analog signal conditioning

• Status indicator LED

• Press button for ending data saving upon payload recovery

• Minimize risk of data loss due to system upset

7

Project Development

• Build a little, test a little• Subsystems were built up on a breadboard and verified:

a)Microcontroller and micro SD card interface

b)Power supply unit

c)Op-amp signal conditioning

• Circuit simulation

8

Difference Amplifier

9

Signal shifting and scaling from sensor input to op-amp output

Implementation

• Compact through-hole part solution for ease of student assembly

• Instructions provide desired level of detail behind understanding the principle of operation

• Prototype tested over temperature, pressure, and time

10

Usage

• Data loggers initially developed for summer camp

• Data loggers are now an education outreach program feature where surrounding schools learn about the device and fly with ANSR

• Original design intent of providing practical electronics exposure to high school and middle school students

11

Flight Results

12

0.00220.16110.32000.47890.63780.79670.95561.11441.27331.43221.59111.75001.90892.06782.22672.38562.54442.70330

20,000

40,000

60,000

80,000

100,000

120,000

Altitude Flight Profile

Time (Hrs)

Alti

tude

(ft)

Max Altitude: 98,633 ft

Flight Results

13

0.0022

0.1061

0.2100

0.3139

0.4178

0.5217

0.6256

0.7294

0.8333

0.9372

1.0411

1.1450

1.2489

1.3528

1.4567

1.5606

1.6644

1.7683

1.8722

1.9761

2.0800

2.1839

2.2878

2.3917

2.4956

2.5994

2.7033

-50.0

-40.0

-30.0

-20.0

-10.0

0.0

10.0

20.0

30.0

External Temperature (Celsius)

Time (Hrs)

Tem

pera

ture

(C)

Project Outcomes

• Embry-Riddle continues to support STEM outreach by offering the use of the data logger

• Practical electronics design work including:

• System engineering

• Product development management

• Printed circuit board layout skills

• Laboratory testing, troubleshooting, and documentation

14

Questions

15