Someone check my math please.... Arduino Shaper Ram FPM Sensor

[deleted_user]

@TorontoBuilder check these out....

Mill Speed Controller

My BB CT129 milling machine uses a 90 volt DC motor with a KBIC-120 variable speed control. Speed is set using a simple rotary pot. There is an auxiliary input that stops the motor without disconnecting power to the speed control. My last project was to build a non-contact tachometer with a...

canadianhobbymetalworkers.com

Bridgeport Mill Tachometer

I am pulling together a control box for my Bridgeport Mills. It is mainly to facilitate VFD controls like a fwrd/rev switch and a frequency Potentiometer. But I have a hankering to be able to see the actual spindle speed. My best idea to do this so far is a hall effect transducer on the nose...

canadianhobbymetalworkers.com

Thanks for the links. I'll read them shortly.

Have a look at these for my current lathe project:

12" x 36" metal lathe VFD conversion and upgrades by TorontoBuilder

When the motor died on our Craftex CT041 12" x 37" gap bed metal lathe my brother and I took the opportunity to make a few planned upgrades including converting the lathe to a 2 HP 3 phase motor with an AT1-2200X variable frequency drive for greater speed control and low end torque. Such a lathe...

www.thingiverse.com

and

https://www.thingiverse.com/thing:5178575

I just can't leave it alone. I'm just sitting watching my 3d printer print a new front panel for my control box because I decided to add forward and reverse jog buttons. Why? Well I ordered what I thought were latching switches and I got momentary switches. So I couldn't let them go to waste.

 

[whydontu]

What's the difference? Looks like the same thing to me.

I have a few crimpers, the trick seems to be being very fiddly about the length of the stripped wire and making sure the connector is wedged properly in the crimping die. I’ll take some photos of my technique. It’s not 100% success rate, but is acceptable.

My experience with the IR sensors is they’re quite sensitive to ambient light. Without a shroud, my tach would stop working in the afternoon when my shop window lit up the shop.

No slur intended, as my coding skills are about equal to my singing skills, but I always look at other peoples code to figure out better ways to do things. The theremin I have is sold by these guys:

Altura MkII+ Theremin MIDI Controller / Arpeggiator - Zeppelin Design Labs

DIY Kit to build a mini digital synthesizer with 13-note keyboard. The Mini-Synth produces a wide range of classic 8-bit sounds.

zeppelindesignlabs.com

The code is open-source, I didn’t dig to deep but there’s probably some way to get the code and compare to yours.

 

[YYCHM]

No slur intended, as my coding skills are about equal to my singing skills, but I always look at other peoples code to figure out better ways to do things.

Yup, I keep looking for alternate implementations. Probably found about 6 so far, but they are all pretty much the same.

I might need a better ultrasonic sensor. The problem with this one is that the duration it returns keeps changing some what even when sounding off a fixed object and the variation gets worse with distance. I don't know why this would be but it does.

 

[deleted_user]

Yup, I keep looking for alternate implementations. Probably found about 6 so far, but they are all pretty much the same.

I might need a better ultrasonic sensor. The problem with this one is that the duration it returns keeps changing some what even when sounding off a fixed object and the variation gets worse with distance. I don't know why this would be but it does.

It sounds like you may be suffering from electrical noise interference, especially in shop environment.

Have you tested the sensor and micro-controller in a different space away from devices that may be emitters of EMI?

 

[YYCHM]

It sounds like you may be suffering from electrical noise interference, especially in shop environment.

Have you tested the sensor and micro-controller in a different space away from devices that may be emitters of EMI?

Currently attached to my PC in the basement rumpus room, no EMI here. Haven't move it to the shop yet.

 

[deleted_user]

Currently attached to my PC in the basement rumpus room, no EMI here. Haven't move it to the shop yet.

well that sucks. have you calibrated the sensor?

 

[YYCHM]

well that sucks. have you calibrated the sensor?

Nothing to calibrate.

 

[Johnwa]

I found this crimper works much better than the model you have. https://www.amazon.ca/gp/product/B0895LN7QS

I have the same on as yours but could never get a good crimp. The dies in the one I linked to are different and work very well. My crimps now look like they’re supposed to.

 

[YYCHM]

I have the same on as yours but could never get a good crimp. The dies in the one I linked to are different and work very well. My crimps now look like they’re supposed to.

Ok, the dies on this one have a distinct jog in them. Is that to be expected?

 

[Johnwa]

Ok, the dies on this one have a distinct jog in them. Is that to be expected?

If it’s what I think you mean then yes. That is the part that crimps over the insulation. Both my crimper s are like that except that one works and other one doesn’t.

 

[deleted_user]

Nothing to calibrate.

when I did my first projects with an Arduino sensor kit I did some calibration work on most of my sensors to fine tune readings. You should do the same with your sensor. I was getting inaccurate measurements over 4 feet. The point is though that you methodically record and graph measurements and that helps you identify a correction factor or see if you are getting inconsistent results in just a specific distance range or all over the place. This helps identify if you have wiring or interference issues.

Ultrasonic Range Finder with Arduino — Maker Portal

A typical healthy human is capable of distinguishing a range of frequencies between 20Hz and 20kHz. Frequencies above this range, called ultrasound, are inaudible to humans because of physical and neural limitations set by our auditory systems. Sound, much like light, is a great scientific tool beca

makersportal.com

 

[Former Member]

Strokes I can count no problem. Trying to compute FPM with any configuration of stroke length on the fly.

Simple spreadsheet, stroke count on one axis, length of stroke on the other. FPM in the middle. Old school.

 

[Susquatch]

@YYCHM - I know little to nothing about the mechanical geometry of your shaper. Can you simply turn the machine by hand to determine the fwd/rev time ratio the old fashioned way? A bad guess could skew your numbers significantly.

I like @whydontu 's idea of using an Arduino. Not just because you can find out the ratio and other parameters, but mostly because it can become a permanent fpm gauge. I've read through the post and wish I had seen it earlier to help with the early math. At this point, I'd just be confusing the matter. Instead, I'll only remind you that fpm is a velocity quantity which is the rate of change of distance with time.

You don't need to position the sensors at the ends of travel to determine it. In fact, that's probably a poor choice. The Arduino can handle measuring the time for any distance and it is plenty fast enough to discern almost any cutting speed that machine of yours can generate. Nonetheless, I would recommend an integer distance of say two or four inches in the middle of the stroke so that you can do the math in your head and know that the output number that the Arduino produces is correct. Calibration in the code or in the sensor spacing will be important.

That said, the sensors do not have to be on the ram. They can be anyplace where you know the geometry and the physical relationship between the parts. In fact, putting them on the rotating parts has the advantage that you can have just one rpm sensor and not have to worry about separating out the fwd/rev strokes.

If you need help with that math, I'll happily engage. I would enjoy looking at the geometry and learning a bit more about shapers. Just ask.

 

[YYCHM]

- I know little to nothing about the mechanical geometry of your shaper......
I would enjoy looking at the geometry and learning a bit more about shapers.

Here you go, knock your socks off.... http://www.neme-s.org/shapers/columns/shaper_column_04.html

 

[whydontu]

Maybe an ah-ha moment? One of the stumbling blocks mentioned is the ram doesn’t have a fixed relationship with the base. The extend and retract movement can be adjusted so the end points are not always a set distance from a reference point.

Is there a sensor to target position that can cover all possible ranges of movement? then you measure A to B, measure B to A, do some math to calculate differences over time.

What about using an 18” or 24” iGaging scale for input?

or could be as simple as a rotary encoder being driven by a toothed belt, such as the ones used for crap 3d printers.

the Arduino programming is way beyond my skill set, but shouldn’t be that tricky for a real programmer

Arduino DRO DIY Build Instructions

Blog dedicated to DIY digital readout TouchDRO and other hobby machining and engineering subjects.

www.yuriystoys.com

Chinese Scales

 

[Chicken lights]

Ok, the dies on this one have a distinct jog in them. Is that to be expected?

Do you have the end in backwards? The part you’re trying to crimp on. My crimpers are made by Grote and they’re fussy too.
I have the best luck starting the to close the tabs with a regular pair of pliers, then using the crimping tool to do the crimp.

 

[YYCHM]

Do you have the end in backwards? The part you’re trying to crimp on. My crimpers are made by Grote and they’re fussy too.
I have the best luck starting the to close the tabs with a regular pair of pliers, then using the crimping tool to do the crimp.

I don't think I'm putting the pins in backwards. I've looked at a few videos and sample instructions.

 

[Susquatch]

Is there a sensor to target position that can cover all possible ranges of movement? then you measure A to B, measure B to A, do some math to calculate differences over time.

That's essentially the first idea I tried to explain - but poorly as usual...... Any distance during the main portion of the primary stroke will do.

Here you go, knock your socks off....

Awesome! Leave it with me!

I don't think I'm putting the pins in backwards. I've looked at a few videos and sample instructions.

I agree with @Chicken lights . Those crimpers work best if you close the tabs a bit first with needle nose pliers. But have a close look at your crimpers first. Some have a spot that acts like a staging crimp to setup the ears for the next operation. They are basically a two stage operation.

 

[YYCHM]

But have a close look at your crimpers first. Some have a spot that acts like a staging crimp to setup the ears for the next operation. They are basically a two stage operation.

Here is a shot of the crimper jaws Two stage? @Johnwa This is what I meant by a jog.

 

[Johnwa]

View attachment 19615

Here is a shot of the crimper jaws Two stage? @Johnwa This is what I meant by a jog.

Yes, the narrow part crimps on the conductor while the larger part crimps on the insulation. Mine never crimped properly on the insulation, it just kind of squashed the tabs on the insulation. My new crimper crimps on both. It is a single operation. There are a number of YouTube video tutorials that may help. Search for “crimp dupont connector”.