next topic »

[Reply #30 on:]

No, that isn't possible directly.

Wow that was very positive. If it is not possible directly, then are there any other way we can do that? I mean getting the amplitude of the return signal?

Regards,

Ashok Srinivasan.

[Reply #31 on:]

Sure boss,

Provided i get an intact tutorial on how to do it. As i was progressing with the project i never knew i will get so much deep into Ultrasounds. Also now the requirements are very much clearer. Contradicting my initial requirements, it has come down to 0.08 mm which is the maximum resolution i would need.

Now the phase of my project is such that i want to accumulate as much as parameters that i can know from the sensor like time of flight(this is there in ping already), next is the amplitude, the return echo signal strength etc., The ping sensor seems to be talking only about the time of flight. I was wondering if there is anything else i can find of use to me for making some initial analysis.

Also thinking(i do not know the validity) since ping sends a pulse to terminate after the echo is heard, will it be a voltage between 0 and 5 or a voltage either 0 or 5(since the receiver generates current upon the echo)? ? maybe they mean something rite Or am i looking at it very easily and this is wrong?


Regards,

Ashok Srinivasan.

[Reply #32 on:]

Contradicting my initial requirements, it has come down to 0.08 mm

You're talking about a resolution of better than 1/100th of a wavelength.

[Reply #33 on:]

You're not going to find any tutorials to guide you along on this project, especially if you keep expecting to use ultrasound.  Expect to spend a significant amount of time researching everything to do with the technology, and be ready to build your own solution from scratch.

Personally I think I would put more thought into an optical solution, something like a strobe light at a very high incidence angle and a macro image sensor observing the surface of the wheel.  Then just look for the amount of pitting on the surface in the shadows.

[Reply #34 on:]

Hello Friends,

Its been a long time since i vanished and not been active on this thread. It was just for the reason i wanted to really navigate away from the ultrasound and look for solution based on optics.

I really wanted to honor and respect the views of the people who wanted to genuinely help me out on this and is the reason for my long silence to come back only after i have done some homework. Now it has come to a point that i have switched to IR. I made an Infrared Meter by reading the tutorial posted here http://elecrom.wordpress.com/2008/02/19/how-to-make-simple-infrared-sensor-modules/#comment-2483 .

I should say it works fairly good and gives me a lot of hope. Though i am not trying to develop an Imaging solution, but simply wanted to find out the loading time of a grinding wheel. With this module i am able to measure the voltage values generated by the IR receiver based on the reflection from the surface by the IR transmitter. It all costed me very less to make this circuit and also it still satisfies my original goal (Cheaper ways to analyze Grinding Wheel loading).  Though the analysis is still left to us, we are monitoring different specimens and are trying to evaluate an average value which will help in deciding about the dressing time of the wheels. Though it is not accurate but it is approximate.

Now is a phase where i have started testing out the unit on different grinding wheel with different loaded conditions. Wish me all the best.

On the other hand i have started looking at the magnetism aspect of testing the loading condition. Since the grinding wheel accumulates a lot of metal particles, was wondering if i can keep a magnet at a minimal constant distance from the grinding wheel and measure the force field between the wheel and magnet if any. Ideally in the starting stages there should not be any force field because of no metallic particles present, as time goes forward a lot of metal particles gets accumulated in the wheel thus should increase the magnetic force between the wheel and the magnet. This would be the theoretical idea, but need to know what are the practical implications of it. Trying to get a hall effect sensor and see if it can cater to this purpose, but am not getting it in my area. Also i need to do some amount of ground work on the IR module and then move on to this solution giving full focus.

I would want to thank every individual in this thread for their time to help me. Once again forgive me for my long absense.

Regards,

Ashok Srinivasan.

[Reply #35 on:]

Friends,

I finished making my IR circuit and happy to say that the module works as desired. I can see a difference of 30-40 mV difference during the grinding process. I checked this with a multimeter. Now i am in the stage of fabricating the IR sensor for good finishing and connecting it with my arduino to read the analog reading which is the voltage generated by the IR Receiver. With this i am now observing different wheels with different grades to esitmate the loading time.

I will soon post the pictures of my test/experiment. Meanwhile thank you all for having supported me through this.

Regards,

Ashok Srinivasan.