Mechanical gyroscopes for vehicles examples wtd

[amorrison]

I want to build a gyro from a motorcycle wheel - maybe about 30lbs including motor to maintain gyro rpm.
Does anyone have any examples of similar size/capability?
Thanks.

 

[drawoh]

amorrison,

What do you want to accomplish?

A gyro either is part of a sensor, or it is very large and heavy relative to what you are trying to stabilize. Ultimately, all a gyro does is increase your moment of inertia. Your system does not move as much in relation to what it would have done without the gyro. Any cables and shaft couplings you have attached to this thing will affect the behaviour.

Where is the motor going to be? I am trying to imagine your layout. This would be a good application for a frameless motor.

--
JHG

 

[IRstuff]

You are probably looking for a flywheel, as opposed to a gyroscope; both have gyroscopic action.

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[1gibson]

Is this for an automobile? Are you trying to reduce body roll? Can't you just put a motor in the spare tire holder in the trunk, and then spin the spare?


Posts like this are difficult when you don't describe what the objective is. Not to mention, a bit boring.

 

[ctopher]

1gibson,
He wrote it's for a motorcycle.

I agree with IRstuff, why not a flywheel?

Chris, CSWA
SolidWorks 14
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[drawoh]

ctopher,

He wrote that it is from a motorcycle. This could be some very crude garage engineering.

--
JHG

 

[1gibson]

Thank you. I don't understand the concept of adding a motorized gyroscope to... An existing motorized gyroscope (motorcycle wheel being used as intended on a motorcycle.)

 

[IRstuff]

Ohhhh...

There's not going to be enough inertia to make it worthwhile, I think. Additionally, the existing bearing interfaces are not suitable for gyroscopic uses. Nor would be be sufficiently well balanced.

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[ctopher]

Sorry, misread "from" as "for".
Thanks drawoh

Chris, CSWA
SolidWorks 14
ctopher's home
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[amorrison]

I want to build a flying platform ~24 ft long, 8 ft wide and 3 ft high.

I am very concerned about the low inertia of the longitudinal/roll axis - if a gust of wind causes severe roll to happen -say 30 degrees in 0.5 seconds the pilot will not be able to react quickly enough.

Therefore -two requirements

1. Quick response to wind gust

A "large" qyro - made from a motorized motorcycle wheel where one can get a large inertia with not much weight because of the large diameter. The gyro wheel "tilt" changes could happen very quickly via hydraulic cylinders controlling the cage that provide force feedback to the main structure in say 0.5 seconds

2. Then the gyro wheel could be brought back slowly -(say 10 seconds) to the "neutral position" buy forces from the main structures aerodynamic controls.

 

[GregLocock]

I would have thought that in context the cost of a properly engineered device would be rather small. Any compromises you make in design to use the OTS wheel will turn up as excess weight or lack of reliabiliry, neither being great ideas in the case of flying machines.

Cheers

Greg Locock


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[IRstuff]

"the pilot will not be able to react quickly enough."

The Apollo space program demonstrated that manual control of flying platforms is very tricky, and a fly-by-wire control system should be used. If you have FBW, then the reaction wheel is probably not necessary.

I think that you are already going to be challenged to lift the platform, and adding unnecessary weight is ill-advised

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[1gibson]

Does the platform have wheels, or will it actually fly somewhere? Trying to figure out why you might consider it a vehicle.

 

[IRstuff]

"I want to build a flying platform ~24 ft long, 8 ft wide and 3 ft high." answers that question, doesn't it?

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[imcjoek]

I want to build a flying platform ~24 ft long, 8 ft wide and 3 ft high.
I want to build a gyro from a motorcycle wheel.
the pilot

So you're building a manned aerial vehicle out of scrap.
I'm simultaneously fascinated and terrified. Anybody got the EAA on speed dial?

 

[drawoh]

amorrison,

Does this platform have wings, or is it being lifted by fans? If this thing is being lifted by fans...

[ol]
[li]...your weight will be more critical than GregLocock and IRstuff are implying. [/li]
[li]...why can't your fans act as gyros?[/li]
[/ol]

I looked into gyro stabilizing a piece of airborne equipment a few years ago. As I noted above, to work, a gyro must be a very large part of the mass of your system, and/or it must rotate very fast. The maximum safe rotation of your motorcycle wheel probably is rather slow. In my case, there were the additional issues of the forces caused by the cables and hoses connected to the equipment.

Gyro stabilizers are active devices that read the position of a small gyro, and then send signals to actuators. This is the bases of the FBW system IRstuff is describing.

--
JHG

 

[JStephen]

http://en.wikipedia.org/wiki/Gyro_monorail

 

[moon161]

Consider precession effects as well, they could compound the danger significantly.

 

[tbuelna]

The device you describe would not be efficient for providing pitch/roll/yaw axis control of your flying platform. You would need at least one such device for each axis. Each one's motor would need to be sized for the max response rate the platform required, which would likely be quite large. And each system would need to be designed to for very high levels of reliability, since if one of these devices were to seize-up it would be a catastrophic failure.

 

[moon161]

Look up the moller volantor while your at it.