Vertical Movement: Alternatives to Using a Cam

[secureprivacy]

Hi

I have a thin box (e.g. like an A4 book) I would like to shake up and down sinusoidally. At the moment I have a flywheel connected to a beefy motor. I have tried using a cam to do it but it has proven not so ideal. What other methods can I use?

Thanks

 

[Rap]

Buy a jigsaw or a reciprocating saw.

 

[omni-impotent]

What's your budget? What period do you need? What amplitude do you need?

You could buy an linear actuator and have complete control over all those parameters. A little bit expensive that's all. :-)

 

[secureprivacy]

Yea its for a school physics competition - so I am keeping things as simple as possible - 1 to 10 Hz and about 5cm max of amplitude?

 

[omni-impotent]

5cm and 1-2Hz seems possible with an actuator. But will be expensive.

Depending on the mass, you could also use a spring?

5cm and 10Hz is quite fast... are you sure your thin cardboard box won't fly apart?

 

[secureprivacy]

Oh just to clarify, its a thin perspex box which weighs about 500g?

 

[AlephZero]

At 0.05m peak to peak and 10 Hz, the maximum acceleration is
(2 * pi * 10)^2 * 0.05/2 = 98 m/s^2 = about 10G.
You will need a rigid connection that can pull the box down as well as push it up, and the force on the box will be 10 times the weight of the box.

For a simple cam you need to keep the acceleration below 1G, otherwise the box will lift off the cam when it is moving down. That will limit you to about 3 Hz with an peak to peak amplitude of 0.05m.

 

[yuiop]

Why not use something like the crank off a bicycle?