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Thread: Reasoning your way through the FSAE design process

  1. #181
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    Goeff,
    FSAE and this forum will be much poorer for your absence until you work through your problems and can return. I am confident that you will reason your way through your current situation, as you have in the design process and project management.

    You and your team earned my respect in 2006 - first as engineers by the performance of your car, then as honorable people by the way you handled the scoring problems.

    “Reasoning your way through the design process” has been required reading for my students since it appeared. It very closely parallels the design process that we teach and applies to much more than FSAE cars. And you present it in a much more eloquent and entertaining way than I. To be sure that they read it, I told them that there would be a quiz; and I had to keep my word.

    Be safe.

    Make McDermott
    Retired Texas A&M FSAE Advisor
    1999-2014

  2. #182
    Senior Member
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    Melbourne Australia
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    Living with Parkinsonís as opposed to reading about it.

    Firstly, this is not meant to be a slight at neurologists, medical researchers, Parkinsonís specialists et cetera. Rather, Iím just putting this up here to present an engineerís perspective of medical research and to give the readers a bit of sense of how an engineerís problem-solving process doesnít only relate to mechanical stuff. And maybe with a bit of feedback from a few non-medically prejudiced brains, we might be able to contribute something to the medical field - if they want to listen to us, that is.

    Now, for those of you who donít know, Parkinsonís disease is a neurological condition (as in, it is a condition of the nervous system, although most people visualise it through its end effect on the muscular system - tremors, loss of balance et cetera). It is idiopathic, as in it has no known definable cause. But it is essentially a set of symptoms that result from a lack of dopamine in the brain.

    Dopamine is a neurotransmitter, which means it is a particularly shaped molecule that bridges little gaps in neuronal circuits to complete the circuit. Iím no expert in this, but basically when you learn how to do something you are effectively strengthening neuronal circuits to complete that task.

    Dopamine seems to have a couple of effects. Firstly it plays some role in your neuronal control systems. Without it, your bodily motor controls seem to go out of calibration. Often this is seen as tremoring, which is analogous to a mechanical control system out of calibration that is overshooting then under shooting then overshooting et cetera.

    The other effect that is significant is that dopamine is one of your feelgood neurotransmitters, the other notable one being serotonin. Both of these neurotransmitters give you a sense of positivity and well-being, and so it is probably no great surprise to find that the recreational drug ecstasy is an artificial boost of serotonin. On the flipside, when you lack dopamine or serotonin, you donít feel good. In fact, you feel pretty black. Go ask your local hippie raver how they feel one Tuesday and Iím sure you will get a much bleaker answer than they would have given the weekend before. Serotonin overload on the weekend, brain registers that it doesnít need to make any more because youíre overstocked, then when the artificial boost wears off, you go into deficit and feel like crÍpe.

    So one of the delights of Parkinsonís disease is that the baseline mood level is hippie raver Tuesday morning. Every day.
    Now my brain does not make dopamine, and I have to get it artificially supplied. The artificial supply is through a drug called levodopa. Levodopa is to dopamine as Nutrasweet is to sugar. It sort of mimics the real thing, but it is never gunna be the same. I have been on a couple of other medications as well Ė one called a dopamine agonist (which helps you process the dopamine you have more efficiently), and one called an MAOB inhibitor, (which help slow down the ďburn-offĒ of any excess dopamine in your system). So you can see that the whole focus of a Parkinsonís medication plan is supply management of dopamine.

    This seems reasonable, in that your healthy brains are making dopamine on command, whereas my brain is getting artificial dopamine in discrete bursts.

    So the medical specialists know what chemical is missing in my brain, and they seem to have a lot of knowledge about how the symptoms present, the likelihood of psychological effects, et cetera. They have seen the movie, if you like.

    Now I donít have as much specific medical knowledge, but I am living this thing. And as a mechanical engineer I have a pretty decent sort of intuition about mechanisms and control systems. I expect some of the readers of this will be the same, so if you have any feedback on what I say please donít hold back. Iíd like to think that a bit of collaborative problem-solving between the chemically minded medics and mechanically minded engineers might make some big steps towards solving this thing.

    Observation number one:
    planned movements are difficult, reactive movements are still fine. A few weeks back I was in hospital and a change of medication left me almost incapable of walking. I could barely put 1 foot in front of the other, and even getting out of bed took every bit of mental effort that I could muster. I tried to go for a walk outside one morning and I could barely make it out to the footpath. I started crossing the road, when a car came around the corner and I panicked. Immediately, I was able to sprint across the road. When I got safely to the other side, I slowed to a walk and suddenly I could barely move again.
    Basically the fight or flight reflex is still fine, but my ability to make conscious decisive movements is highly compromised. This sort of makes sense. If you loose some of my functionality due to the lack of a neurotransmitter, it evolutionarily makes sense to jettison the low risk activities first and keep whatever dopamine youíve got for the life or death, fight or flight stuff.

    Observation number two:
    when I am high dopamine, walking is a natural function. When I am low dopamine, it is like walking becomes conscious effort. Basically what Iím saying is that when the dopamine is gone, it is like I lose the pathway to learned patterns of activity, and I have to solve all of the balance problems and motion problems of walking with my short-term memory. I find this really interesting.
    There was the video going around Facebook couple of months back about robots having difficulty walking. It looks hilarious as these humanoid machines just seem utterly perplexed solving simple problems like standing up or opening a door. To be honest, when I saw that video I could actually feel what they were thinking. Not that Iím saying the robots are consciously thinking like we are, but I had a sense of the mechanical problems they were trying to solve. They were getting stuck in all these do loops, and just falling over. Been there, done that.
    The first thing I thought I saw this video was that the robots were trying to solve the problem of walking with their RAM memory. There was no intuitive background pattern of walking or standing in printed in their memory banks. It made me think hard about my own situation, and that maybe dopamine is role to play in accessing learned patterns of behaviour.

    Observation number three:
    the muscular stiffness that the doctors tell me about isnít actually stiffness. What I mean by that, is that for example when my shoulders feel stiff, the muscles arenít actually tense.
    As an example, I had an example a couple of months back where I completely froze up and we had to call an ambulance to take me to hospital. I felt stiff all over my body and I was in a heap of pain, but when the paramedics arrived to pick me up I was actually completely limp. I was actually flopping around like a rag doll.
    What it felt like was that my nervous system was completely lost and that every muscle in my body is somehow being primed for movement then not getting the signal to do so. It actually felt like Iíd gone completely out of calibration, and that my whole body was getting low intensity signals as a calibration test to find out exactly where the muscles were and what they were up to. This leads to what I think is my key observation.

    Observation number four:
    I reckon the Parkinsonís problems a calibration problem. And I think the key to the problem is surprisingly enough stretching and yawning.
    Once again I was in hospital pondering my navel when I felt the urge to yawn. It was one of those really unsatisfying yawns that doesnít seem to go anywhere. I tried to yawn again and that didnít work. This happened about four or five times. The following morning after Iíd taken the dopamine tablets I felt the urge to yawn again. This time the yawn was one of those really deep and satisfying ones that starts with the yawn and ends with a full body stretch that lasted for 10 seconds or so. As soon as I done that, I realised my body was fully functional again and I was able to walk around like a normally could.
    I tested this over a number of days, to the point where I consciously stretch yawn on command. Before Iíd stretch yawn Iíd be feeling wobbly and out of calibration. After it, Iíd be at greater control of my physical motor functions.
    Geoff Pearson

    RMIT FSAE 02-04
    Monash FSAE 05
    RMIT FSAE 06-07

    Design it. Build it. Break it.

  3. #183
    Senior Member
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    Location
    Melbourne Australia
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    So my hypothesis:
    I think the yawning and stretching process, as demonstrated in all vertebrate animals, is actually a kind of neurological calibration process. It is the body resetting itself after the night’s rest or before a high stress event. Note that a lot of Olympic athletes yawn and stretch before the start of their event.

    Think of it this way. Overnight, the body repairs itself and any damage done over previous days and weeks. So effectively when you wake up in the morning your brain is driving a different body than what it had been the day before. The muscles are actually operating at different efficiency levels than they were the day before.
    No just imagine if you’d been calibrating your ECU for a certain set of injectors. Then overnight the cleaners came in and fitted in all new set of injectors with completely different performance maps. Your mapping would be all over the shop, and you would have to recalibrate. Well, the brain has to do that every morning.

    So when I started to think about how the brain might do this it gave me a different insight into the hole yawning and stretching process. In a good yawn and stretch every muscle in the body is lightly tensioned and then ideally taken through its full range of motion. It’s almost a semi-static sort of a proportioning test, where for example the biceps and triceps lightly pull against each other to establish equilibrium points throughout the range of motion.
    Why start with the yawn? Well, the facial muscles are the first branch of the nervous system south of the brainstem. Why not start there? What happens next? The yawn and stretch proceeds down the spine to lower muscle groups in a kind of geographical progression.
    It explains why the yawn involves opening the mouth wide, but not really taking a lot of air. We are stretching and testing the muscle, not respirating.
    It explains why yawning is contagious. If your evolutionary rival is priming and recalibrating their nervous system, then you had better do it too.
    Yawning is apparently the last unexplained aspect of our behaviour. Hopefully, I am on to something here.

    Getting tired, time for bed, more later. Sorry it is not about race cars.
    Take care.
    Geoff Pearson

    RMIT FSAE 02-04
    Monash FSAE 05
    RMIT FSAE 06-07

    Design it. Build it. Break it.

  4. #184
    Ops!
    Something Perfect had disappeared :/

  5. #185
    so sad that first post is gone.

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