Sensors

Thanks.

I guess I was thinking like $100 USD.

When I searched on "impulse measurment techniques" I am getting fairly technical things, research papers and such.

Can you help me find a particular website?

like a

getting

travel.

If I understand you correctly, then you might consider putting an accelerometer on the hammer. That won't tell PSI because you won't know the contact area, but it may allow you to derive a useful number.

What is it exactly you are trying to do?

Bob Masta dqatechATdaqartaDOTcom D A Q A R T A Data AcQuisition And Real-Time Analysis

If you are looking for sensors then industrial sites are the place to look but "something cheap" depends on your definition.

What you are describing though is not just a sensor but a complete instrument. If you are a looking for something that measures the force with which an oboject is being hit you might refine your search to impulse measurment techniques.

If you are looking for sensors then industrial sites are the place to look but "something cheap" depends on your definition of cheap.

What you are describing though is not justIf you are looking for sensors then industrial sites are the place to look but "something cheap" depends on your definition.

What you are describing though is not just a sensor but a complete instrument. If you are a looking for something that measures the force with which an oboject is being hit you might refine your search to impulse measurment techniques. a sensor but a complete instrument. If you are a looking for something that measures the force with which an object is being hit you might refine your search to impulse measurement techniques.

Finding something that will do the job without being destroyed could be a challenge an accelerometer attached to (or embedded in) an object of known mass might be a good start.

Some sites:

You are too quick for me I was in the process of modifying this when you responded.

Something simple like a pedulum bob and a scale to see how far it is displaced when hit? Phil

Analog Devices have integrated circuit MEMS accelerometers on their site. They use a mass and spring microengineered out of silicon to measure accelerations of up to about 50 g.

Or you could put a sheet of rubber between two metal plates and measure the change in capacitance?

What's that Lassie? You say that studio fell down the old sci.electronics.basics mine and will die if we don't mount a rescue by Mon, 16 Aug 2004 21:49:58 -0400:

I think what you want is a pressure transducer. They can be had from surplus stores. I think I saw them at C+H sales.

That, plus a small hydraulic cylinder, will give you an analog signal proportional to the force applied to the piston rod of the hydraulic cylinder.

The transducer works like the sending unit on your car's oil pressure gauge. You will need something to store/read the output if you need to see the results of a fast event like your hammer example. For slower events a DMM should be fine. You will need to test it with a known force, and you will need to chose a cylinder that has the proper bore(area) to create the PSI that the transducer is rated for.

Good luck. Dan H.

I've never used 'em, but how about a strain gauge attached to the side of a rod with known (or measurable) elasticity? Like a nail maybe :-) You could either integrate the output to get the total impulse delivered, or peak-detect it to get the maximum force.

--You might try posting this to rec.crafts.metalworking; there are quite a few folks up to strange stuff like this over there..

-- "Steamboat Ed" Haas : When did 'Pledge Week' Hacking the Trailing Edge! : turn into 'Pledge Month'?

It depends what you are trying to do, and just how much force you expect to measure. Here are a frew ideas:_

1. Load cell. A bit expensive to bash, but protect with a large plate. read the output faster than you would a load cell in, say a weighing scale. Analog Devices, and Maxim, among others have dedicated devices for converting and amplifying load cell signals.
2. Known mass with accelerometer on surface of known coefficient of friction.

1. piezo element, protected. measure the voltage spike.

2. accelerometer in flexible lever, like the old school ruler twanging.

1. as above with piezo

2. Accelerometer on the object your bashing with. Know the mass of the object and the acceleration allows you to derive force.

1. lever element arranged to electrically detect moment of contact with the object. A microswitch under neath, or laser beam, allows you to determine the force the lever was struck with, based upon the time it took from impact to switch operation.

Cheers

Al

The resistance of the black foame used for shipping devices sensitive to electrostatics depends on pressure. A little bit from the last shipment of ICs is the cheapest sensor I know of.