Anyone remember "The Amazing Accelerometer"?

[prfesser]

I hate it when I get these flashes of memory because sometimes I can't tell whether it's my imagination...

Anyway...a few centuries ago, when I was a kid, I remember that a rocket company (definitely not Estes but beyond that I dunno) had a device called The Amazing Accelerometer. Supposed to give some kind of acceleration measure, obviously. Back then electronics often involved tubes or large transistors, so this had to be mechanical. I think it was quite inexpensive for what it did.

So...can anyone enlighten me about this device? Did it actually exist? If so, who made it, how did it work, anyone here actually buy and use one?

Thanks in advance -- Terry

 

[jsdemar]

Model Rocketry, June 1971


It was also marketed as the AMROC accelerometer:
https://plans.rocketshoppe.com/pubs/Amrocs/Amrocs_Accelerometer.pdf

 

[Donnager]

Sounds like it works the same way as one of these:

 

[Funkworks]

Edit: I answered my own question so ... um ... yeah, what a neat device.

 

[manixFan]

Ok, my visual OCD got the better of me and I had to fix that PDF. I converted it into single pages that are rotated correctly and added OCR so it is now searchable.

For the probably 2 people that will look at it!


Tony

corrected PDF of Amrocs Accelerometer manual:

 

[jqavins]

So I presume it gives you only peak acceleration? Now, if the paper could be made to rotate during flight...

EDIT: Never mind the question. I read the manual.

 

[prfesser]

Thank you all. I had envisioned a device that rotated during flight to give an acceleration curve. Still...not bad for the 60s.

Best -- Terry

 

[ben]

Ok, my visual OCD got the better of me and I had to fix that PDF. I converted it into single pages that are rotated correctly and added OCR so it is now searchable.

For the probably 2 people that will look at it!


Tony

corrected PDF of Amrocs Accelerometer manual:

Thanks

 

[vcp]

Sure, I had one. The recording paper was red-wax coated, and the scribe was a triangular lead weight. Only flew it a few times, but it actually gave some very clear readings, including a readily apparent 'jiggle' of staging on a two-stage flight.

Fun gadget, highly educational, and brilliant for its time. Oh, and when I had it, it must have been in the mid '60's.

 

[Steve Shannon]

Who was the person behind “Rocket Supply Company?”

 

[Blast it Tom!]

Downloaded and saved! Great look-back piece. Thanks!

 

[Nytrunner]

I ghess I got lost along the documentation. Is the wnd result of this acceleration trace just a single line that extends as far down as G's compressed the spring? Not exactly an A vs t graph?

 

[jsdemar]

I ghess I got lost along the documentation. Is the wnd result of this acceleration trace just a single line that extends as far down as G's compressed the spring? Not exactly an A vs t graph?

Just three lines from the triangular weight. There would have to be a rotating paper roll or weight to get a curve.

 

[Nytrunner]

Just three lines from the triangular weight. There would have to be a rotating paper roll or weight to get a curve.

Thats what I figured. Interesting little science package. The manual's math section would have been very useful in its day

 

[aerostadt]

I probably saw this idea somewhere in the 60's and built one from scratch. I flew it once and got a peak acceleration that was in the ballpark and so I considered the flight a success. For wax paper I used the same paper that RDC used on their static thrust stand. Their static thrust stand was also a cool device.

I actually went on from that idea and built a similar device that measured air drag at the front of the rocket. I got one measurement that I thought was in the ballpark.

 

[ksaves2]

There was a transmitter I once made called the “Foxmitter” that was published in “Model Rocketry” magazine. It was a multi-specialty radio transmitter that transmitted on the CB band. There was a plug at the base that one could plug in different modules. One was a simple resistor that would configure the transmitter to transmit a simple “beep”, “beep”, ”beep” for RDF purposes or other modules. I remember there was an accelerometer module that had to be calibrated. I had purchased all the parts and constructed everything.
It all worked but I never flew it as I moved on into high school and lost interest. I found the box with all the stuff in it 25 years later and I connected up an old 22.5v Burgess battery, turned on the old walkie-talkie and it worked! Alas, the box was lost in one of the moves to different jobs so all I have left are memories now.

Ooopsy. There was also a photocell module that one could plug into the transmitter with a light blub to take the pulse rate of a mouse that one was “supposed” to be launched in a multi-stage rocket!! That was before the prohibitions on launching mammals up in rockets!! One was to line up the light bulb to reflect off the chest of the poor mouse and have the photocell aimed to pick up the variations of reflections that would be encoded to a varying tone that would be transmitted by the Foxmitter which if aimed right would pick up the pulsation of the poor mouses beating heart. It was suggested to use a stop watch and cassette recorder to record the beeping sound of the mouse’s heart. Once restrained, one was supposed to wait for the pulse to stabilize and then launch. Reportedly, the pulse rate would go up under acceleration and stabilize later only to go up with the ejection charge under zero “G“. I didn’t build that module as I felt even then it would be a negative thing to have a deployment failure with a mouse onboard. I once had a pet white mouse who was a sweet companion for the few years she was alive. I couldn’t have pictured risking her in one of my risky rockets! Ended up happily in the backyard pet cemetery after her life was over.

The same guy that came up with the Foxmitter, I believe his name was Richard Fox, did a little RDF transmitter called the “Minimitter”. Just transmitted a silent carrier RF signal. Had to make a “decoder“ that one had to tune and have next to their walkie talkie in order to “hear” a beep tone. I flew it once, it worked but it was superfluous as the rocket came down within sight. I did experiment with a coat hanger loop antenna clipped to my retracted walkie talkie antenna and I remember it did exhibit directionality. I moved on into High School, studies and didn’t have time anymore. I studied a lot and no I didn’t discover girls then. I knew they were there but had too low of a self image to ask anyone out. That came later during graduate medical training. Oh, I wished I still had that box of Rf stuff I made in the eight grade but I don’t think 22.5V batteries are available anymore. Kurt