Project Counter Spin is ready and we launch tomorrow! After launch there will be a hike to recover it. The balloon will be filled to go to about 85,000 ft and land approximately 50-80 miles from the launch location.

I have lots of pictures, diagrams, and fun project related stuff to put up after finals are over.

(The original launch date was delayed one week from April 7th to April 14th on account of wind).

I got to get my hands dirty making an e-glass test structure.

E-glass is a fiberglass cloth that is sopped with epoxy. The fiberglass cloth makes it strong in tension and the epoxy makes it more rigid.

The awesome thing about e-glass is that is can be molded to make almost any shape: airplane wings, rocket fuselages, car bodies. It is also very light weight, and extremely strong in tension and moderately strong in compression.

The cloth used in E-Glass Composite.

To create our E-Glass structure we first cut the e-glass fiber into the shape we wanted. We used a 6 inch PVC tube tube, laying out the E-Glass into a cylinder shape around the pipe. We then used paint brushes to apply the epoxy mixture over the fiber. We were very careful to not allow the epoxy to bond the PVC pipe to the e-glass material.

Here you can see us painting epoxy onto E-Glass Fiber that has been wrapped around a 6 in pipe.

Before we allowed the epoxy to dry we placed another layer of the E-Glass material directly on top of the first layer and painted it on as we had for the first layer. This second layer gave the structure even more strength.

After it dried the E-Glass structure easily slid off of the PVC pipe.

After performing a basic “smoosh test” we decided to add a third layer of E-Glass to further increase the rigidity of the structure. Because we added the third later after the first and second layers had dried we got a few air bubbles in the epoxy but it wasn’t an issue.

Here you can see the acrylic heat bending and the c clamps that were used to press the acrylic into place.

In order for the camera to see we had to create a “window.” This window consisted of a piece of clear acrylic plastic that we heated to a high temperature and bent around the 6 inch PVC pipe. Also, in the background of the picture you can also see the finished e-glass cylinder.

This is the finished outer structure, still waiting for that painted flame design.

After finishing the window and the e-glass we cut the pieces to size and we used hot glue to connect them together. We added sandwich foam end caps for the cylinder and cut holes out of the caps for the brass connection rod.

After a long couple days fabrication the outer structure is done. Except it needs a paint job. Someone suggested an R2-D2 design, but I’m thinking black with blue flames – like a meteor careening through Earth’s atmosphere .

Problem Definition

In November 2010 several payloads were sent up to 85,000 ft by a standard weather balloon. In the picture below you can see the layout of the payloads on the weather balloon.

This picture shows a balloon launch how the payloads are arranged.

The payloads and weather balloon are connected with rope. The rope is not rigid and twists very easily. As the balloon travels upward, it encounters atmospheric winds. The atmospheric winds blow on the payload imparting a moment about the rope that causes the payload to spin about the vertical axis.

The picture to the left shows a launch. From the picture you can get an idea of how the balloon and its payloads are connected.

The video below shows the stability problem in action.

The goal of this project is to, within the constraints of a payload, create a single axis attitude control system that will make a video of the flight worth watching.

Flight Profile — About the Weather Balloons

The weather balloon pictures above is attached by rope to several payloads. Each payload is a contained structure weighing less than 2 lbs [.9 kg]. The payloads on the top and bottom contain GPS sensors and RF transmitters which are used to track the balloon through it’s flight.

The weather balloon is filled to a capacity that determines its flight profile. The balloon reaches a certain altitude at which the atmospheric pressure decreases enough to cause the balloon to expand and pop. The gas used by the balloon is Helium and typically it can lift 20 lbs to altitudes up to 125,000 ft [38 km].

Once the balloon pops, despite its parachute, it falls like a rock through the less dense layers of the atmosphere. Once the popped balloon reaches a lower altitude its parachute catches and its payloads safely land (hopefully .

Counter Spin Requirements

1. Mounting

The payloads have a bronze 10 mm lamp rod going through them with an attachment point on each end for ropes to attach. Project Counter Spin must use the same mounting method to attach to the ropes.

2. Weight

The aggregate weight of the entire payload system including the mounting rods must not exceed 2.25 lbs and preferably weigh less than 2.00 lbs.

3. Control System

The control system shall provide one dimensional attitude control for a video camera mounted on or within the payload. The camera footage shall be bearable to watch and preferably beautiful.

4. Other Sensors

The payload shall also contain an accelerometer, pressure sensor, and temperature sensor. Preferably the payload shall contain a solar cell and outside temperature sensor. The sensors shall be used to collect and record their data for post processing.

Project counter spin is an attitude stabilization project for a video camera placed on a high altitude balloon. You can see footage below of what happened to the video camera last time it got sent to 100,000 ft.

The wind gusts in the stratosphere are pretty rough. The wind caused the payloads to spin fast enough that the video camera footage made me sick.

So the plan is to make the video camera footage useful. Launch is T-minus 2 months and counting. Time to get cracking and hacking.

Expect more soon