Controlling Tremors As They Happen

Some neurological disorders, like Parkinson’s disease, can cause muscle tremors which can get worse as time goes along. In the beginning it may not be too difficult to manage, but as the disease progresses the tremors get worse and worse, until day-to-day movements are extremely difficult. Even picking up a fork or pouring a glass of water becomes nearly impossible. Some helpful tools have been designed to limit the impacts of the tremors, but this new device seeks to dampen the tremors directly.

A research team from Fresno State has been developing the Tremelo, which is a hand stabilizer that straps onto the arm of a person suffering from tremors. It has sets of tuned mass dampers in each of two enclosures, which rapidly shift the weights inside to counter the motion of the wearer’s tremors. The device has already shown success in 36 trial patients and does an incredible job at limiting the amount of tremors the user experiences, and also has a bonus of being non-invasive for the wearer.

The team has successfully trialed the program, but is currently seeking funding on Indiegogo. The project seems worthwhile and is a novel approach to a common problem. In the past, devices (admittedly with a much cheaper price tag) try to solve the problem externally rather than in the direction that the Tremelo has gone, and it’s a unique idea that shows a lot of promise.

25 thoughts on “Controlling Tremors As They Happen

    1. Then I won’t be so polite. They are asking for $900 for each device, to be “dedicated” to someone in need. For a mass-on-spring inside a box.

      Sure, they had development costs to come to that design, but now they are trying to rip people off with an excuse of charity.

      1. Yeah its pricey but do you want to strap a large dampening mass made by anybody to your arm.. Sure it might work nicely but if it is overly heavy or too easily effected by magnets, dirt, oils it could actually cause more problems than it ‘fixes’.

        I’m sure with some work and research time a 3d printed design will happen.. and whichever kind soul printed it will probably be reprinting it quite often as life will be pretty hard on a 3d print strapped to an arm. This looks like it will probably outlast the patients and work with no fuss to keep it moving correctly.

        Machinists/fancy CNC machine time isn’t free. And is even less free for short run oddities as it is much quicker per part to bash out 100’s of the same part than 10. If this proves to be half as good as it looked I expect the price will plummet pretty quickly as there are enough folk that could use it. But as it stands now in small scale that actually seems to be a reasonable price.

        1. You sound like you have a horse in this race.

          Why would a bad device cause problems? If it doesn’t work, just stop using it, why would it cause more problems? How would magnets effect it unless you bring any magnets close to it?!?

          Sounds a lot like scaremongering to me.

          I won’t argue machining is expensive, and development takes a lot of time and effort that also needs to be payed, but your arguments seem disingenuous.

          1. It doesn’t appear to say it anywhere, but this is almost certainly going to be a medical device that falls under the purview of the FDA. Getting FDA paperwork in order for this device would likely cost around $50k. The clinical trials to prove any claims could cost much more.

            I mean sure, anybody would be allowed slap something like this together and put it on themselves, but selling it in the US could be non-trivial unless you make absolutely no claims about what it’s supposed to do.

          2. I have no skin in the game. I’m just saying a weight that is magnetic or can get magnetized could stick/seize and such thus making it ineffective (as you say not the end of the world, but if you need the device to allow you a normal life its worth paying for one that will work properly).
            Even worse if the mass really does become a magnet moving them could potentially induce current in other devices that can’t take it. And finally if it the mount to your arm isn’t well designed the damping forces could be concentrated and actually harmful, especially to older folk with brittle bones.

            I’m not saying its a complex or hugely dangerous idea, because clearly it isn’t. But being something that I would say is essential to the users life you want it to work – Not sort of work but need tinkering/repair/cleaning every other day. You also absolutely want it to have no chance of causing harm. So to avoid issues with it and keep it running for ages you want a properly engineered one made in the right materials which is where it gets pricey, at least without real mass production – which might not even be possible for this device I doubt its one size fits all for all the parts.

          1. Devices like this need not be FDA licensed before being marketed (IANAL let alone a medical lawyer).

            As a low risk and therefore “general” classification think bandages, plasters, tongue depressors.

          2. I think Alex Rossie could be completely incorrect about classifying this as class I device. As others have said, it could potentially injure the patient (skin irritation, skeletomuscular injury, cutting off circulation, etc), and I would think this would warrant an FDA clearance under class II classification.

    2. True. The two main things that need figuring out are the mass of the blocks, whose inertia should counter the arm movement, and then the spring constant which is determined by the tremor frequency.
      Mind you, I still think it’s an ingenious invention, I’m not saying it’s not a clever idea of the inventors.

          1. While you are correct that they had different purposes, they both rely on the same underlying principles. The unit in the article has masses moved by magnetic fields, tesla’s ‘building shaker’ had a mass moved by steam. Different power source yes, but the same effect of a tuned resonance.

          2. Ah! I did not RTFA well enough. It is a passive resonator, ‘powered’ by the shaking of the body and disrupting that. I guess that means it is externally powered as well in a sense ;)

          3. Uh, no. Did you not read the article, or just not comprehend what it says? The proposed device here uses no magnetic fields, and no power source. It’s an entirely different thing.

  1. I find it hard to believe such a small device, especially limited in the sideways direction in which much of the tremor seems to manifest, could house a passive mass-spring-damper system sufficient to achieve the results as shown, with hardly any visible tremors remaining in some cases.

    It seems to imply the tremors are resonant oscillations, which seize when the Q-factor of the system is sufficiently reduced. Even if that’s true, it would have to be tuned for each user individually. I’m not saying it’s fake, but I’m skeptical.

    Although it did get me thinking, would it be possible to dampen the tremors using electrical stimulation?

    1. This.

      A small tuned mass damper like this must have a relatively high Q, and a passive system like this won’t easily adapt to different frequencies.

      I can see how it can work nicely when tuned for a particular person, in a specific posture, for a specific task, using a specific load mass (like a spoon or a glass), and for as long as that person’s tremor frequency doesn’t otherwise change.

      It makes a great demo, and demonstrates the mechanical engineer responsible is competent, but as a general purpose aid, it’s wanting.

      This is begging for an adaptive, active mass damper that can adjust to the task. Sure, it will require power, but opens up a much greater range of tasks it’s useful for.

      1. @SparkyGSX I think electrical stim is also being researched, I think by a university group in the UK.

        @Paul, it appears that at least per person the frequency is constant for 90% of the parkinson population.
        A passive system must be tuned with the damper mass and the spring constant to counter the movement.

        If the mass were a DC motor driven mass and a microcontroller would measure the high pass filtered position signal with an accelerometer, then the system could be made adaptive.
        If the mass is large enough, you don’t have to move it a lot to counter the movement. Of course for heavier movements you need to move the block more, and if the block is too heavy it becomes cumbersome.

        1. I wonder if you could use something like a magnetorheological damper/shock absorber to make the system a little more tolerant of different motions and tremor frequencies. Use an accelerometer to look for modal freqs that aren’t being suppressed and tweak for that? Not my field but could be cool.

  2. That’s quiet neat. They aren’t claiming any new technology but adapting technology already used in machine damping just applying it to a human body. (This is pointed out in the video)

    Even if the device has to be tuned for a specific application for a specific patient. And is not as effective for other applications that is still a win. It now means they can go out for dinner and eat it and not wear it that’s awesome.

    We seem to put more emphasis on finding a “cure” for terminal illness which only delays the inevitable. Rather than improving the quality of the life we already have.

  3. For those asking about electric stimulation there is Deep Brain Stimulation (DBS). It’s very expensive and requires electrodes to be put in your brain as well as a computer and battery device in your chest and tube from your chest to your brain. they have to drill nickel sized holes in your head to install the device. It’s very expensive, but it is covered by insurance.

    There are several companies that make devices that compensate for your shaking when eating. I believe the oldest is liftware which was financed by someone from Google who has Parkinson’s. When I originally read about these products the spoons seem to work pretty well, but the forks did not. Parkinsons for the 70% of the people who have a tremor affects fine motor functions. That’s what I have, though the major symptoms are unseen which are pain and stiffness. The main medication carbidopa/levodopa seems to reduce the tremors, but not for fine motor functions with me. Eating can be frustrating. I told my wife we need to eat more steak because I can poke the steak and shaking doesn’t matter that much when you poke food.

    I also did see a YouTube video of a device from England that goes around your wrist and dampens the tremors. They showed the device working for an artist who had Parkinson’s with tremors. I believe there was a computer involved and it was not a passive device. That was probably four or five years ago.

    Parkinson’s is called a boutique disease because there are a lot of symptoms, but not everybody has all of the symptoms. For instance 70% of the people with Parkinson’s have a tremor and 30% don’t have a tremor. For years I was misdiagnosed because they thought my tremor was too fast for somebody with Parkinson’s. The voice volume of someone with Parkinson’s often gets lower and lower as the disease progresses. I’m just as loud as of always been. They have figured out between talking with friends, family members, and old coworkers that I first started having symptoms in 1996. I was finally diagnosed as having Parkinson’s in 2013.

    This may work and may not work. We will have to see.

  4. This product is targeted at Essential Tremor though it most likely can be used for Parkinson’s. ET is not fatal but can become very debilitating as shown in the video. Millions of people in the US have it, many more globally.

    The current treatments for ET are mainly drugs and then Deep Brain Stimulation for the most serious cases.

    It is good to see this kind of attention being paid to ET and other tremors; there has not been real improvements for many years. There have been a couple of gyroscope systems to counter the oscillation and at least one vibration motor system but I have heard of no truly successful attempt so far.

    A couple from Hackaday
    Local electrical stimulation: https://hackaday.com/2017/10/01/hackaday-prize-entry-hand-tremor-suppression-wearable-device/
    Gyroscope: https://hackaday.com/2017/05/03/hackaday-prize-entry-analyzing-and-controlling-hand-tremors/

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