For Spring 2016, the challenge for Rocket Engine Development Stand Team was to determine how to collect the load cell data in a safe and secure manner. Together, we came up with three methods and chose the final method based on budget-efficiency and feasibility.

The Stand Team had $100 to spend on both anchoring the rocket stand and wiring the load cell for data collection. We split the cost 70% – 30%.

Our methods, from most ideal to practical, were using:
1. a XBee Shield to send data with radio frequency
2. a Data Logger Shield to store data onto an SD card
3. an USB-Ethernet extension cable to transmit data directly to a computer
We evaluated each choice and decided to choose the USB-Ethernet extension cable based on the following reasons.
Data Logger with SD card
– Benefits:
– connects directly to the Arduino therefore it is reliable and avoids data loss
– Allows Arduino to function on its own
– Pre-made code exists as well as an extensive how to manual
– It is reliable and reusable. Only need to buy new batteries for a power supply
– Downfalls:
– expensive, $50
– Doesn’t retrieve “live” data recording
– Soldering the datalogger shield to the Arduino is needed
– Materials and Costs:
– Datalogger ~ $20 (Adafru)
– 2 G SD card – $7

XBee Shield
– Benefits:
– avoiding a wired connection for safety reasons
– Signal extends to over 100ft according to the Arduino website
– Can retrieve a live data streaming
– Downfalls:
– Over the budget, almost $90 including all the additional components
– Making a unique code for our connection – limited time
– Need lots of additional components (cellphone “hotspot” or a portable wifi-router)
– Materials and Costs:
– XBee Shield~ $15 (SparkFun)

USB-Ethernet Extension Cable
– Benefit:
– Get a live stream of data
– Ensure connectivity
– Downfalls:
– Short length
– Signal may be weakened, unable to get data from arduino
– May need additional components (powered usb hub)