×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Contact US

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Determine relative positioning of objects in a confined underwater environment (small tank of water)

Determine relative positioning of objects in a confined underwater environment (small tank of water)

Determine relative positioning of objects in a confined underwater environment (small tank of water)

(OP)
I am designing a system that will allow me to take measurements of ultrasonic sound waves with an Onda hydrophone in an underwater environment. The ultrasonic transducer will be inside a water meter. The hydrophone will be mounted to a 3D gantry system allowing me to move it precisely around the portion of the water meter where the sound waves are localized. My current plan is to mount the water meter to the frame of the gantry system. But my question to you guys and gals is how do I determine the relative position of the hydrophone to the water meter? My idea initially is to use some sort of fudicial markings on the meter to indicate where features are located on the meter. How do I sense/measure my postion relative to those fudicial markings in an underwater environment?

RE: Determine relative positioning of objects in a confined underwater environment (small tank of water)

Not clear what you are describing - you say the transducer is mounted inside a water meter (I'm envisioning a water flow/totalizer meter like is connected to my house, i.e. something about the size of breadbox or smaller), and then you say a hydrophone (same as transducer?) is mounted on a 3d gantry that moves around the water meter, then you say (3rd sentence) you are mounting the water meter to the frame of the gantry...which I think you mean the gantry is attached to the wall of the water meter?

Maybe a sketch would clear things up?

Bottom line is - if I'm reading your mind correctly - you want to move a hydrophone around inside the case of something bigger, and know where the phone is relative to the bigger case. My answer would be to measure where the gantry moves relative to its mounting points, and then to also know where the gantry mounting points are relative to the case where it gets mounted. Presumably you will send a signal, or count revolutions of a stepper motor or similar actuator that moves the 3d gantry, and would know from those signals and your measurements where the hydrophone is subsequently located. Doing all of the setup work on a lab bench, where you could directly measure and calibrate your gantry control/signal systems might help a lot too.

RE: Determine relative positioning of objects in a confined underwater environment (small tank of water)

Are both the hydrophone and the "water meter" mounted on the frame ? ... can't be ??

We're talking small distances, right ? I like the idea of stepper motors to control to the position of both sensors, like two sets of x- and y- axes. Else maybe something like a camera focus ?

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


Resources

Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Design for Additive Manufacturing (DfAM)
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a part’s function at the center of their design considerations. Download Now
Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close