A more detailed explanation is not a "dumbed down" explanation, but rather one with no details missing. When I expain a project to a master mechanic I do not tell them how many bolts to use, or what size, unless there is a very specific reason, because they already know. But for a beginner I add a of the details, because they lack experience. Sometimes I even explain why a thing is done a certain way.
The challenge here, in many instances, is that others presume that we are familiar with the context of what they are asking about, and that is seldom the case. In another nearby thread the question is about "an AC motor", which had us going for a while, unti we were shown the picture and the manual for the machine that the motor was a part of. Suddenly al of the previous suggestions were miles off base, because the problem was actually not a motor problem. But until we had that information we were a guessing.

 

I am asking experts to "dumb down" a solution for an amateur which is not appropriate for this forum.

No.

It is completely, totally, and absolutely appropriate for this forum.

I am out of my league and do not expect a beginner's tutorial.

No.

We all were beginners at one time, although clearly there are some who have forgotten that little fact. Still, this forum is better than most in handling beginners. Some would scare you.

I am sorry if I wasted some of your time(s).

Think about this. You came here with questions because we know more about this stuff than you do. That's a given. Not only is there nothing wrong with that, it is the only reason this forum exists.

BUT -

When it comes to your question, you are the *only* one who knows anything. Simplifying the question is exactly the wrong thing to do. Pile on everything you know right up to the limit of what you can disclose. It will save a lot of electrons.

ak

 

I am asking experts to "dumb down"

 

This is probably the best information you've provided in the whole 80 post message thread.
You can probably just use toggle switches and relays (maybe not relays).

However, what did you mean to say here?:

"If the bottom is first, a the other one illuminates, not the top. "

The "a" is a typo. I will elaborate but it will get lengthy using words, The weakness of this analogy and the golf club is that the "switches" here would have to be a beam or laser since both swings are super fast. The principle is the same. So forget the beam. This example would be useless to a tennis player but demonstrates the functionality. Lets say there are two rods which protrude horizontally from the device into the path of the racket - one at the top (T) and one at the bottom (B). These operate two NO temporary switches in the device. Bring the racket through SLOWLY. If the racket is leaning forward, it will brush against rod T closing its switch. Light T will illuminate (GREEN for example). Naturally the bottom of the racket will also brush against rod B a microsecond or whatever later. Switch B will also close but it is too late. Light B can not illuminate. Player only knows the top came through first. As the racket loses contact with the rods they spring back to their neutral OPEN positions and the unit is ready for the next stroke. Next time, let's say the bottom rod is pushed forward first. B is illuminated (YELLOW for example). The top beam will be interrupted again a fraction of a second later, but T won't illuminate. That's it. Originally I envisaged a perfectly perpendicular racket (in this analogy) and THAT was to be the 3rd light (GREEN) but only (if possible) when both switches closed at precisely the same time. I'm sure you and colleagues can incorporate that but for me, the T and B lights are fine.

I am going to try to post another general reply thanking everyone for all to see. Hope it succeeds. I have more than enough feedback already to keep me busy.

Brewster

 

The "a" is a typo. I will elaborate but it will get lengthy using words, The weakness of this analogy and the golf club is that the "switches" here would have to be a beam or laser since both swings are super fast. The principle is the same. So forget the beam. This example would be useless to a tennis player but demonstrates the functionality. Lets say there are two rods which protrude horizontally from the device into the path of the racket - one at the top (T) and one at the bottom (B). These operate two NO temporary switches in the device. Bring the racket through SLOWLY. If the racket is leaning forward, it will brush against rod T closing its switch. Light T will illuminate (GREEN for example). Naturally the bottom of the racket will also brush against rod B a microsecond or whatever later. Switch B will also close but it is too late. Light B can not illuminate. Player only knows the top came through first. As the racket loses contact with the rods they spring back to their neutral OPEN positions and the unit is ready for the next stroke. Next time, let's say the bottom rod is pushed forward first. B is illuminated (YELLOW for example). The top beam will be interrupted again a fraction of a second later, but T won't illuminate. That's it. Originally I envisaged a perfectly perpendicular racket (in this analogy) and THAT was to be the 3rd light (GREEN) but only (if possible) when both switches closed at precisely the same time. I'm sure you and colleagues can incorporate that but for me, the T and B lights are fine.

I am going to try to post another general reply thanking everyone for all to see. Hope it succeeds. I have more than enough feedback already to keep me busy.

Brewster

Hmmm...I don't mean to discourage....but if your thinking about producing a product, I would investigate using motion analysis software. There's probably software that can already do this or be modifed to do this.

But meanwhile....we'll digest the info you've provided...

 

As the racket loses contact with the rods they spring back to their neutral OPEN positions and the unit is ready for the next stroke.

So would the introduction of a set delay, after which the light that is lit turns off automatically, meet your requirements? If so, that would avoid having latching arrangements which would need resetting.

 

Actually I designed, and our company built and sold, quite a few laser beam break speed measurement systems twenty years ago. They are used for precision speed measurement in automotive component crash testing systems. So if you needed to measure the speed of a golf club or tennis racket it would simply require new fixtures to hold the lasers and the detectors so that the beams are parallel and exactly 4.000 inches apart. The system resolution is 0.01MPH, while the accuracy is +/- 0.015 MPH. (after calibration.)
I could share the circuits but unfortunately I do not have the software that converts the time to a velocity display.

 

Good clear explanation. What you want is a modified "game show" circuit a) for only two players (top and bottom) and b) is self-resetting. It could either reset completely (no lights) after x seconds, or hold the last result until the next swing, seconds or years later. Also, since there is no such thing as a tie with nanosecond-speed electronics, I recommend a third output based on a narrow time windoe.

Dinner. More later.

ak

 

Hmmm...I don't mean to discourage....but if your thinking about producing a product, I would investigate using motion analysis software. There's probably software that can already do this or be modifed to do this.

But meanwhile....we'll digest the info you've provided...

Thanks for the tip. I did some research on proximity sensors instead of switches but was not convinced I could find ones that would work,

 

Actually I designed, and our company built and sold, quite a few laser beam break speed measurement systems twenty years ago. They are used for precision speed measurement in automotive component crash testing systems. So if you needed to measure the speed of a golf club or tennis racket it would simply require new fixtures to hod the lasers and the detectors so that the beams are parallel and exactly 4.000 inches apart. The system resolution is 0.01MPH, while the accuracy is +/- 0.015 MPH. (after calibration.)
I could share the circuits but unfortunately I do not have the software that converts the time to a velocity display.

Impressive! Speed measurement is not really a requirement in this case. Guess you managed to build your own radar/laser detector for your vehicle! No reply necessary!

 

After reading the extended explanation of the purpose in post #65, I understand what I think is the application, and what you need is laser beams and silicon sensors. The actual logic can be quite simple. The best deal on suitable lasers came from "creative Technologies" company, so do a web search and you will need to call them as they do not seem to open emails.
The same sensors could certainly show which beam was broken first and display that and the logic would be much cheaper than relays

 

What about this:

Top leads Bottom = Yellow LED

Bottom leads Top = Red LED

Red and Yellow are mutually exclusive

AND

Separate from either of those:

Top and Bottom are within 10 microseconds (or whatever) of each other = Green LED

Now you see that you were within the sweet zone, and still get an indication of tilt.

? ? ?

ak

 

After reading the extended explanation of the purpose in post #65, I understand what I think is the application, and what you need is laser beams and silicon sensors. The actual logic can be quite simple. The best deal on suitable lasers came from "creative Technologies" company, so do a web search and you will need to call them as they do not seem to open emails.
The same sensors could certainly show which beam was broken first and display that and the logic would be much cheaper than relays

Sounds great MB2! I have seen that manufacturer's name before

 

Good clear explanation. What you want is a modified "game show" circuit a) for only two players (top and bottom) and b) is self-resetting. It could either reset completely (no lights) after x seconds, or hold the last result until the next swing, seconds or years later. Also, since there is no such thing as a tie with nanosecond-speed electronics, I recommend a third output based on a narrow time windoe.

Dinner. More later.

ak

Thanks AK. Wish I had thought of that example earlier.

 

So would the introduction of a set delay, after which the light that is lit turns off automatically, meet your requirements? If so, that would avoid having latching arrangements which would need resetting.

Can that delay be a second or two?

 

Can that delay be a second or two?

Since the fast sensors deliver a logic level transition it will be very simple to trigger a monostable such as a CD4098 or MC14538, or else a "flop-shot" using a CD4013. so an illumination time of several seconds is easily provided. The really difficut part of the project will be to make the frame stiff enough to hold the 1mm laser beam on the 3mm sensor window.

 

Sounds like a perfect example. Thanks

Yikes! "Scaled to my ignorance." Actually that was well said and you are correct. I am asking experts to "dumb down" a solution for an amateur which is not appropriate for this forum. I am out of my league and do not expect a beginner's tutorial. I am sorry if I wasted some of your time(s). I think I will take what all of you have offered and go back to the library to bone up on basic electronics. My electrical knowledge is high school level from the '60s. Transistor radios were the latest invention. To answer the many curious here is the best analogy I can muster - can't give specifics if this is ever commercialized. Let's assume you want to analyze your tennis stroke. Is your racket leaning forward (topspin), back (backspin), or perpendicular? You swing on front of a device - probably with lasers or a beam rather then a mechanical switch, and swing. If the top of the racket breaks its beam first, one light illuminates - not the 2nd. If the bottom is first, a the other one illuminates, not the top. That's it- end of cycle - the only feedback you receive! Naturally the other side of the racket WILL break its own beam but it is too late. You get one or the other. Same could be for a golf club - toe first or heel first, but this one would require super speed.

Hope this clarifies it but I have so many responses now I am not sure I can keep track. The forum is more complex than the circuit!

Brewster

I'm sorry if you think I was belittling, that was not my intention. While you might imagine we are looking down on you because of your ignorance I assure you those among us who are likely to be most helpful understand that ignorance is a temporary condition that can be dealt with, unlike stupidity which is terminal.

If you sensed any frustration it arises from two things:

1. Your desire to place bounds on the solution that do not exceed what you imagine is your current knowledge. That was the meaning of "scaling to your ignorance", not as you seem to think, an unwillingness to teach. It's quite the opposite, in fact.

2. Your attempts to conceal your real problem by inventing, what you think, are analogous problems. Think about it, if you don't know how to solve your problem how can you hope to create an analogy that would allow us to do it? Instead you will inevitably do what you have done, slowly in a tooth-pulling fashion add information as we insist on knowing it, and present entirely new—but imaginary—analogies because you are afraid of revealing something.

An additional problem is the idea that you would have people here consult, gratis, on a commercial product you imagine has value only if it is kept secret. My suggestion is that you hire a consultant, have them sign an NDA, and pay them for their time.

Ironically, it is very unlikely that revealing your actual idea would change the marketability of it and people would be happy to help even if it is a product you will make money on. If you do bring something to market that worth selling it will be only a short time before copies from China appear for a fraction of what you have to sell yours for to be profitable anyway, so it is not the idea you need to protect, it is the quality and customer service after the sale.

Good luck with whatever it is you are trying to do.

[EDIT: changed "which" to "what" in 2.]

 

"Product development Engineering" is functionally what a few of the folks who participate here either do, or did. In my case, at one job, it was a customer arriving with a need to identify some characteristic of some product in order to verify that it was OK to sell, or include as a part of a larger product. So developing a concept as to how that happens and then developing the design of a machine or system to carry out that process in a safe, accurate, and reliable manner was the engineering part.
So some of the folks here are able to provide a lot of value, but most of them have poor mind-reading abilities and require an accurate target to aim at.

 

This goes back to something I did for an Experimental Psychology lab in the early 1980's. I've got a demo circuit down to three chips plus one stupid little XOR gate that is bugging me.

Three indicators:

1. Red - forward tilt
2. Red - backward tilt
3. Green - near-zero tilt

Two latches (one chip), one for the tilt indications and one to show when the tilt is almost zero.

Two monostables (one chip), one to discriminate near-zero tilt and one to enable all outputs for 5 seconds. The output timer can be replaced with a manual Reset switch.

Three output enable gates (one chip). A manual Reset switch eliminates this chip.

One stupid little XOR gate (one chip). This turns two input signals into a single pulse whose width is the time between the inputs. The more narrow this pulse width, the closer the swing is to zero tilt.

WAIT - just had a thought about a different approach with fewer parts. More later.

ak

 

What about this:

Top leads Bottom = Yellow LED

Bottom leads Top = Red LED

Red and Yellow are mutually exclusive

AND

Separate from either of those:

Top and Bottom are within 10 microseconds (or whatever) of each other = Green LED

Now you see that you were within the sweet zone, and still get an indication of tilt.

? ? ?

ak

That would work. The more I thought about it myself the more I realized that simultaneous would be very near impossible. As youo said, within the zone would be good enough feedback.
Thanks
Brewster