Stochastic To Deterministic

When considered as a separate environment, the habitat is in itself a system that can be modelled via complex system theory. However it is not a simple mathematical exercise. The habitat is linked to the real world, and follows the laws of physics. Knowing this, has allowed me to foresee the patterns that would be prevalent in this mission.

I was fully aware that the first three to four weeks of this mission would be borderline chaos and highly stressful. It would then slowly settle down into a more periodic system with its own rhythm and would be highly predictable.  Strictly speaking, the beginning of the mission would be more stochastic and non-linear than the middle and the end. Patterns of behavior interjected with sometimes massive random fluctuations in behavior. This was represented dominantly by the number of power/water/equipment issues. It was taking a hot liquid and dumping it into an empty container – the dynamics of the liquid are wild and seemingly chaotic at first. But the liquid will eventually settle into an equilibrium with its container. It would transition from a stochastic system into one that is deterministic and predictable.

I believe the habitat has finally reached that stage. The equipment issues have been worked out, the people inside have found a certain routine that repeats. It has moved into a periodic cycle that is dominantly predictable. This is good news for me. I can get to know such a system. I can almost sense the state of the habitat, what it needs, and can start to predict more accurately requirements of things like water and power, effects of a cloudy day versus a sunny one, the time it takes for the solar heated water to warm up in the morning and cool down at night, the amount of water used in the washing machine on the ‘normal’ or  ‘high’ setting, or the combination of appliances we can use in the kitchen without popping a breaker, etc.

For me, I hope, the hardest phase of the mission is coming to an end. Things should be dominantly routine from now on so long as I keep an eye on the habitats needs and wants. I have to protect it from any form of stochastic fluctuations that could occur.  These come in more extreme forms, such as using 5x more power in a day than average could upset the system, or having several cloudy days in a row. Given that many of the items in the habitat are new, I should not be faced with complications of appliances breaking down often. However, with sex crewmembers cooking, cleaning, exercising, working, and living, many of the appliances, fixtures, and systems here get a lot more use than they have initially been intended. It is important that I keep my eye on them, maintain them, and try to minimize the impact once they do break down.

‘Murphy’s Law’ is always in the minds of anyone in an engineering position. Murphy is a beast that cannot be slayed, but it is predictable because we know that it will be there. Thus this allows one who is fully prepared to keep Murphy at bay.

This past week saw major issues with the water pump. All has been quiet since, and I hope it remains that way.

SOL 16

We got the HMI panel display that indicates the status of the generator viewable on computers in the habitat. This will allow me to keep a closer look at the generator situation now on. The robotic companion study continues with Pleo as it is taken care of by a different crewmember each day. Pleo seems to be well liked among the crew and is sometimes the center of attention when it is powered up.

SOL 17

Enough data has been gathered that we are able to make some reasonable estimates of water and power usage. Dominantly, the crew will use between 35 – 50 gallons per day. The variation is caused by our Navy showers, laundry, and cooking vs. Pre-prepared meal days. Power usage is dominated by the use of space heaters to keep the habitat warm. We are looking at ways to reduce power usage, such trying to finish all cooking activities prior to sundown as we will draw most of the cooking energy off the solar panels in this manner.

SOL 18

During my routine checks, I found that the water pump was leaking out of one of the connection pipes. It was dripping at about one liter an hour, so I placed some buckets under the pump to capture for dish washing. Communication with Engineering support lead to a decision for engineering help to come fix the issue (I did not have the needed tools) in the next day or so. I spent the day emptying the buckets every few hours.

SOL 19

Friday, day started out pretty normal and calm. Then in the morning meeting there was a very loud bang followed by the sound of a large amount of water splashing coming from the robot garage. I have heard many explosions before, and knew the pipes had given out. The crew ran to the container where water was shooting out of the pump, a flood of water was on the floor and everything on my workbench was soaked. The crew started to rush the boxes of food out of the container while I first shut off the valve from the main water tank, and then tripped the breaker to the water pump. Due to the pressure the water was still flying out of the tank. The pipe that connects directly to the 90 degree angle on the pump had dislodged, I then forced the pipe back into its connection despite the really hot water streaming out. It took a few moments for the pressure to die down enough for me to stop it. After that, I spent the morning soaking up the water from the container, and getting heat and ventilation moving through the container.

SOL 20

The water tank ran out a couple hours prior to being refilled. We spent a few hours today waiting for the water refilled before cooking. This caused a late dinner, but it was not a major issue overall. Getting the refill timings for the water and controlling water usage is one of the major challenges for this mission. Eventually I will know when the water is going to run out days before it happens with greater confidence. Overall, one of the better days in the habitat. Water full, water pressure is good, and we have power. What else could a habitat engineer want?

A new water pump was put in place, eventually a re-circulation system will be installed to ensure that hot water will reach the taps in a more reasonable amount of time. These past days were dominated by work on food surveys, smell test, and other scientific studies in the habitat. Pleo has moved on to the Crew commander who spent some time with him. Overall things have finally quieted down in terms of engineering Issues. Our movie night was moved to tonight (Saturday) and we watched ‘Piled Higher and Deeper’, a movie about graduate school life that is frighteningly accurate.

—Simon Engler