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26 April 2024 07:08
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Question |
| Asked by: |
Glenn Hawkins |
| Subject: |
The speed of precession |
| Question: |
If a 3 ½ inch Tedco gyroscope (87 mm) circles a pedestal 10 times before it tilts 20 mm, the ratio of precession to descent would be, ( 87 mm x pi = 275 mm . 20 = 14:1)
Then the ratio of distance traveled between precession tilt and would be 14:1.
The question becomes, what conditions can alter this ratio and by how much?
Very important for me to know is this. How may one increase the speed of pression while caring far greater mass, without increasing the tilt distance? Hypothetically, it seems possible that the ratio could become extreme (1,000,000 : 1) more or less.
We are fully agreed, Blaze and surly some others, that a gyro must tilt to some measure in order to precess at all, but what is the threshold of minimum?
I am seeking input, guys, Help me.
Glenn,
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| Date: |
14 December 2012
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Answers (Ordered by Date)
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| Answer: |
Blaze - 15/12/2012 02:51:55
| | | "a gyro must tilt to some measure in order to precess at all, but what is the threshold of minimum?"
The minimum amount of tilting is entirely dependent upon the system being studied with the various frictions and dead mass probably being the largest contributors to increased tilting. Likely the easiest way to reduce the amount of tilting is to use a large diameter flywheel, a high flywheel rpm, a short arm, minimal dead weight and minimal down force (gravity couple). LIke everything in life, it will be a tradeoff where altering some of the parameters works against your goals and some work towards your goals.
regards,
Blaze
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| Answer: |
Glenn Hawkins - 16/12/2012 17:43:13
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thank you Blase. What I am concerned with is: How may one increase the speed of pression while caring far greater mass, without increasing the tilt distance?
That is; greatly increasing the speed of precession, while simultaneously decreasing the distance and time of corresponding tilt.
That is; if you increase the speed of 360 degrees precession to 100 revolutions per second, can you corresponding decrease the distance of tilt to 1 cm per second?
I thank you can. Does anyone have any ideas on this? How might this be accomplished?
Glenn
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| Answer: |
Glenn Hawkins - 16/12/2012 17:54:32
| | | In the above example consider the nomenclatures of the 3 ½ inch Tedco gyroscope. While you are at it imagine the imposable. Imagine this little Tedco with its known measurements, weighs 100 pounds. Do you see the question better? I don't want to do triad offs. Try to overlook my poor effort to explain, while you think about the question. If you like I will try again.
Thank you.
Glenn
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| Answer: |
Blaze - 16/12/2012 21:43:18
| | | Glenn, my experiments have shown that there is a "speed limit" for orbiting precession (OP). The speed limit is fairly slow if you want to prevent centrifuge and unwanted "dragging" of the pivot. The speed limit for OP changes depending on the system parameters but for SMALL gyro systems seems to have a limit of about one OP for every few (2 or 3) seconds. That is, if the gyro's OP is faster than about once every three seconds the pivot starts to get dragged around significantly. Please keep in mind the 3 second rule is VERY APPROXIMATE and can change quite a bit depending on system parameters, especially when varying the flywheel rpm.
There may be a different speed limit for larger systems but I have not done enough work with larger systems to determine what it would be. Best I can say is that, based on the limited work I have done, there appears to be a slower speed limit for large systems (it takes more than 3 seconds per OP, maybe even double or triple the number of seconds per OP, to prevent dragging the pivot around, but again this would have to be checked out with more experimentation). By the way, the math doesn't give any indication that there may be a speed limit but from what I have seen, it is definitely there.
The speed limit rule generally means that you cannot have fast OP for any system. There is no way you can get a gyro's OP up to 100 times per second without dragging the pivot all over the place in the process. Which means that about the only way you can do what you want to do (increase impact) is to increase the mass of the flywheel. This should not increase the tilting rate if all other parameters are kept the same.
regards,
Blaze
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| Answer: |
Glenn Hawkins - 16/12/2012 22:34:20
| | | Hi Blaze,
I understand perfectly and I diffidently receive more knowledge from this, your reply. I will try to put some sequence to it all. Hopefully I can get to the point eventually. It is difficult.
Regards,
Glenn
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| Answer: |
Glenn Hawkins - 17/12/2012 01:23:55
| | | Blaze.
I have finally solved this my old thought problem. It will be possible to increase angular momentum, while also increasing mechanically applied tilt force to result in fast precession speed, without encountering much pivotal reaction. It is simple. We have determined in the most general, common experiment that the distance precession travels is much further than the drop/tilt correlating distance of travel. The ratio will vary depending on this and that, but we may chouse14:1 as a reasonable example. At this ratio we are familiar with all the effects. The same relationships must follow the ratio 14:1 more or less relating to angular momentum and force of tilt. (the length of shaft from pivot to wheel controls not only speed and distance, but leverage also.
It seems with a good design of proper size and proportion, tremendous collision force could be had quickly and repeatedly. Even however, if this weren’t true (but it is) it in itself would not defy the concept of inertial propulsion. This is so because only during the tilting acceleration could there be normal reactions occurring at the pivot. The acceleration of tilt is opposed by an exponentially increasing counter force coming from increasing deflections. The faster it is forced down, the greater it is opposed. The ultimate speed of tilt is reached very quickly then, as Nitro and Momentous are fond of saying, “instantaneously”. They are very close sometimes if not exact. Once the ultimate speed per design is reached, tilt force stops accelerating and a study speed between tilt and precession is balanced and the pivot behaves. There are other ways to avoid the interference of equal and opposite pivot reactions, but it seems unnecessary to state them. (I will mention it later, but I have seen that you know it for your own design.)
I have what I want theoretically. I have blinding precession speed at only a fraction of tilt misalignment necessary and minute pivotal interference. Thank you for the help. I really did find your replies helpful. You are a very bright young person.
Cordially yours.
Glenn
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