Velocity Analysis

Jaciel S.

Hello I am a·beginner using the BASIC stamp, and what I am trying to do is measure the velocity of a moving object using a basic stamp and a Parallax Ping sensor.· The problem is that I can not work with decimals also trying to capture 2 distances and then dividing them by the time it took to get the 2 distances.· If any one has tried to measure velocity before using a basic stamp and a ping sensor please help me.

allanlane5

Well, the 'ping' sensor is more for finding the distance from a slow moving robot to an obstacle the robot may have to avoid. If you're looking for 'velocity' faster than a robot can move, the Ping sensor is probably not the way to go.

Also, the BS2 cycles at about 2000 Basic Instructions Per Second. It does have instructions which can read a pulse width down to 2 uSec resolution -- as long as that's all it's doing at the time.

KenM

Can explain in a little more detail about the object you will measure, I am sure we can make suggestions knowing more information.

Also, what is the expected min and max velocity of the object?

Jaciel S.

I am attaching my pictures of the structure that I am using, I am asuming it as a two story building wich is vibrating or moving left to right.· I need to know the velocity of the vibration or swing that the structure has.· I dont know the exact minimum or maximum velocity this is what I am looking for.· I am also attaching my code.
If I can not use this sensor to know the velocity do you have any idea how I can measure velocity of this vibrating structure.

Thanks

Tom Walker

Depending on your max and min, the Memsic should come in handy.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Truly Understand the Fundamentals and the Path will be so much easier...

Bruce Bates

Jaciel -

I suspect the sensor you want to use in an application like this is an accelerometer which will measure acceleration and thus velocity, via v = dt^2 if I remember correctly. I'm not all that familiar with the use of an accelerometer in an aplication like this, but I'm sure others will chime in as they read this thread.

Regards,

Bruce Bates

RancheroMan

I was thinking accelerometer as well…….

As for integration, like you Bruce, I’m sure others here will have had experience with some units they can recommend.

I think Tom was on the right track with the Memsic…..

http://www.hvwtech.com/pages/products_view.asp?ProductID=373

Post Edited (RancheroMan) : 6/23/2005 7:25:58 PM GMT

Paul Baker

I am on the same page with the others, an accelerometer (or gyroscope) is the best sensor for this application. Parallax also sells the Memsic 2125 dual axis accelerometer, also on the page are articles and code examples for interfacing a stamp with the device.