Launches for Whitworth University
Launches for Northwood Middle School
With support from NASA's Washington Space Grant Consortium, Whitworth University is partnering with Northwood Middle School to bring high altitude science into the middle school classroom. Whitworth students work closely with the 7th and 8th graders at Northwood Middle School to design experiments that are then sent deep into the stratosphere.
- Spring 2013 (Mr. Gamon's 7th grade SpaceEx class)
- Fall 2012 (Mr. Gamon's 7th grade science elective class)
- Spring 2012 (Mr. Gamon's 8th grade science class)
Balloon system informationStratoStar. I have been very pleased with the system and their support. If you are an educator interested in starting your own ballooning program, I highly recommend contacting them and participating in one of their hands-on workshops. More details about this system are found below.
Communications and Tracking
- Command pod: The command pod contains the primary flight computer, a GPS receiver, a balloon-to-ground radio, and a pod-to-pod radio. It is typically attached below the parachute.
- The balloon-to-ground radio is a 900 MHz device operating in the ISM band (industrial, scientific, and medical band). The ISM band can be used without a license. Other examples of ISM band devices include Bluetooth wireless networking at 2450 MHz. The major advantages of the 900 MHz band are that it operates over a longer range than the 2450 MHz band and consumes slightly less power. The radio system that we will be using is capable of transmitting at 115 kilobytes per second in both up and down links. This is over double the data rate of a dial-up modem (56 kbps) but significantly less than DSL (768 kbps) or cable (6 Mbps) high-speed internet service.
- The GPS receiver updates the coordinates of the balloon (longitude, latitude, and altitude) approximately once every 30 seconds. These coordinates are then transmitted by the balloon-to-ground radio.
- The pod-to-pod radio establishes a wireless network between the command pod and the sensor interface modules located in the experiment pods.
- Sensor interface module: The sensor interface module has 8 digital inputs and ten 10-bit, 0-5 V analog inputs. These readings are relayed to the command pod via a short-range wireless network (pod-to-pod radio) which then retransmits them using its balloon-to-ground radio.
- Mobile Base station: The base station consists of a 900 MHz radio, magnetic-mount antenna for top of vehicle, and a laptop computer. The 900 MHz radio link allows the computer to be in continuous contact with the balloon’s command pod via the balloon-to-ground radio. If everything works properly, GPS coordinates and data from the experiment pods should be received throughout the flight. The laptop is equipped with mapping and data logging software. We have two base station units, allowing us to have one at the launch site and another with a vehicle initially positioned near the estimated landing site.
Balloon and Parachute
We typically use a 1600 g latex weather balloon filled with helium. This allows us to lift 10 pounds (4500 g) of payload to approximately 100,000 feet (30 km). Most recently, we have been using a balloon manufactured by Hwoyee and sold by Scientific Sales, Inc..
A 72-inch diameter parachute is attached immediately below the balloon. The parachute is slack during ascent and fills on descent when the atmospheric density produces sufficient drag.