Thursday, July 22, 2010

High Speed Liquid Observation Platform - Fluid Deployment Bus

As part of my preparations for the September Zero-G flight, I started thinking about improvements to the High Speed Liquid Observation Platform (see 2 posts prior to this one for details on how it works. In particular, I became concerned about the problems of quickly deploying the water globes during the microgravity cycles.

My problem is this: each phase of the flight consists of 5 cycles of microgravity followed by double-gravity. Each half-cycle is about 20 seconds long, so I have 20 seconds to deploy, film, and recover water globes, followed by 20 seconds flat on my back in 2G to reset for the next cycle.

This presents a significant problem, since the reset involves stowing the deployment devices used in the previous cycle, and prepping the new devices (including unsealing them so the water can be released). Not only that, during microgravity, I have to be able to position myself, control the camera, and deploy up to 2 water globes (so I can hopefully collide them).

Yikes. That's a lot of logistics, and since one hand has to control the camera rig, I only have 1 hand and 2 legs remaining with which to do all this.

After a lot of thought, here's what I came up with:

The steel ring is where the diaper-lined plastic bag that collects the water globes will go, and the baby soda bottles are the deployment devices.

Each BSB (these are 2-liter soda bottle preforms, damn near unbreakable) has a rubber stopper in it that has a tube running through it. The tube runs down to the bottom of the tube. The way it works is simple -- you uncork the BSB, and stick the tube that extends past the stopper into your mouth. Gentle puffs then push the water out of the tube.

The tubes are angled and positioned so that a water globe, after being deployed, should float on a path that takes it right through the camera's field of view at the proper distance. And if all goes well, two simultaneously deployed globes should hit each other at just the right place.

During the 2G period, reset involves either restoppering the tube or tucking it through a loop to keep it from floating loose, then unstoppering 1 or 2 bottles and putting the tubes in my mouth. I have timed this process and my first attempt took only 12 seconds.

Of course, I have no guarantee that this deployment method will actually work, so I'll have other methods available just in case. And I also need to think about how to keep myself stabilized and still be able to easily position myself in order to track the wandering globes of water.

But that is the subject of another post.