A few mods/projects for my TaoTao Atm-50 A1 By glavey (Read 25,058 times)

[glavey]

Oct 13, 2014 14:29:56 GMT -6 richardv said:

...
But, why blame an inanimate object. ...

Because you can feel and act out hatred toward an inanimate object without feeling remorse afterwards. Also, most inanimate objects can't hit you back.

I'm not blaming my scooter or anything else for these occurrences; It was meant to be more of a remembrance of what has happened during the building and modification of my scooter. I guess I could have chosen a better name.

[richardv]

Maybe I was a little cold with that. I apologize if your were offended.
By all means take it out on a thing rather than yourself or some one else.
Best wishes.

[glavey]

Nah, I wasn't offended at all; don't worry, man. I just wanted to explain what I meant by what I had typed. That's one of the problems with communication via text; it can be very difficult, if not impossible to include tone-of-voice, subtext, and "it's not what you say, it's how you say it."

I won't gush out my heart's feelings in this thread, but I will say that I didn't know the man very much. I'm not sure if that is a good or bad thing.

Now I'm using the project as something to focus on to keep my mind off of other stuff.

[glavey]

I've been testing the hall effect sensors to see what kind of signal they send out when used with a rotating wheel with magnets on it. First I tried a very small wheel with two magnets in it attached to an electric motor I salvaged from a printer.




I know this isn't how the magnets are mounted on the flywheel on the scooter; this first test was more of a functional test, to see if the sensor worked at all.



I got a clean sharp signal out of the sensor. The electric motor spun up to (as best as I could measure) about 14k rpm at around 17 volts. The sensor gave a crisp signal at those speeds, so I'm sure it will have no problem with the scoot's engine.

Next I printed a much larger wheel, again with 2 magnets but this time with the poles facing the sides, not the front, like the scooter's flywheel.



The sensor still picked up the signal just fine. Since this wheel was a much larger diameter and was moving a fair bit of air as it spun, the 100mA wall wart I used with the motor on the last test could only spin the motor up to 3700-4000 rpm at 9 volts.

I do have an old pc power supply lying around I could use to give it 12 volts.

I still haven't checked to see if the trigger magnet on the scoot's flywheel has the right pole facing out so the hall effect sensor will trigger. If it doesn't, I'll have to tap into the signal coming from the trigger pickup and condition it for the arduino.

Edit:
Well, crap. I tested the hall effect sensor on the trigger magnet and... nothing. It is either too weak or has the wrong pole facing outward. Looks like I'll have to measure the rpms from either the trigger pickup or the primary side of the spark plug coil.

I can still use the hall effect sensor to measure the speed of the scoot.

[glavey]

No, I'm not dead.

I won't go into too much detail, but a sequence of events happened that demanded nearly all of my time for a few months.

During that time, my only mode of transportation was my scooter. I still can't believe I went out when it was 10° and had just snowed the previous day.

I'll continue this thread once the temperature outside has risen well above freezing.

[cyborg]

IT LIVES!!!!!!!!! Geez dude where ya been besides hidin out from 20 below?

[glavey]

Places I thought I'd never go, places I never wanted to go, and everywhere in between. Also, the bathroom.

[cyborg]

,,,,i can relate

[glavey]

Well, I've been able to make a proof-of-concept model for the analog tachometer. Everything from the code to the wiring is still very rough, but it does work. One small change; instead of a stepper motor to move a needle I am using a servo. I bought the smallest hobby servo I could find on eBay (seriously, this thing fits on the pad of my thumb).

I'm not sure if I will stick with the servo or try again with one of the stepper motors. One of the reasons that I used the servo was because there aren't any libraries that I could find for the IC on the stepper motor driver I bought. All of the ones I could find were for stepper motors connected directly to pins on an arduino, not through a driver.

Also, the datasheet says I shouldn't use more than 20mA to drive the stepper motors, but the driver board I bought will only go down to about 150mA. I haven't given up on the motors and the driver yet.



The painkillers in the picture were absolutely necessary.

At the moment there is some electrical interference from the hall effect sensor wire switching from 5v to 0v at up to 150Hz. I think a decoupling capacitor or something similar is needed.

I have the tach updating every 100 milliseconds or 10 times per second.

Here is a short video showing the tach setup in action. Again, the random jittering is from the electrical interference. I am pressing my finger against a flywheel with magnets in it being picked up by the hall effect sensor.

[richardv]

Good to hear your still among us. I don't fully understand what you are speaking of but still find it interesting. Much has changes since I dabbled in such things in about 1990 when I moved out of the boring city and bought a house out in the country and on a lake.
Now being retired I wish I could find a home course such as I took from NRI just before they closed there doors. I have been looking for magazines like I used to get but find none in the stores. These days everything electronic is trough away rather than fixable.
Best wishes and be careful with those pain pills.

[glavey]

Mar 6, 2015 19:37:19 GMT -6 richardv said:

...These days everything electronic is trough away rather than fixable.
Best wishes and be careful with those pain pills.

That is very true. It seems everything nowadays is disposable; cars, cellphones, computers, marriages...

I'm not sure if I mentioned this before in this thread, but with the help of a doctor I found out one of the causes of my headaches: high blood pressure. I'm in my twenties and I have high blood pressure...

Since then I have cut out all caffeine except for tension headache/migraine medicine which has that as an active ingredient, but I very rarely take those. I also stopped drinking 99% of all carbonated drinks. In the past year I have had 2 small cups of sprite when nothing else was available, that's it. Now it's just water and milk for me.

[glavey]

Well, since it is going to (supposed to be) a real nice week, I think I'll take my scoot out for a spin a few times to see what hasn't broken.

I've kept a battery tender on it all winter and started it once in a while to keep things lubricated.

On a side note, I had an... occurrence at one of the radioshack stores that is closing near me (oddly enough, there is another one just a few miles away that is still open). I went in there to see what all they had left and what kind of discounts they were offering. Everything was at least 50% off, going up to 70%.

One of the employees there told me that earlier that day a fellow came in and said (regarding all the electronic components like fuses, resistors, switches, etc.) "I'll take all of it." The employees started emptying all of the drawers of components into two or three boxes and several more bags. Once half of the drawers were emptied, the fellow changed his mind and decided he didn't want any of it.

So, the entire stock of electronic components were completely unorganized in 3 boxes and even more bags. I happen to be looking for a bridge rectifier and anything else that piqued my interest. I asked one of the employees if what was in the boxes and bags was still for sale and he said yes, of course! He even brought out a empty box that I could put stuff that I didn't want into so I could sort through everything easier. I sat in front of 2 boxes and 3 bags of components for at least an hour, throwing everything I didn't want into the empty box and keeping a handful of things that I thought I could use.

I ended up with a 25A 50V rectifier, a LM317T voltage regulator, and a mobile phone toolkit (plastic spreader, miniscule screwdrivers, tweezers like needles).

All together I paid about $12. I don't think that was too bad.

[glavey]

I went out for a short ride today to drop off some mail and see if I could get a new sim card for my phone. The scooter ran quite well. I could tell the cold air was making the engine lean. A couple times at stop lights the engine stalled when I went to take off. A few twists of the throttle and a push of the starter button solved that.

For as long as it is "cold" outside, I'll just keep gently revving the engine at lights so it won't stall on take-off. If I wasn't so lazy I would install a one-size-larger idle jet.

On the way back home I stopped to top off the fuel tank. I prepaid $2. I loved the look on the attendant's face when I came back to ask for the change.

The oil cooler is still working, although it took the entire ride for the temperature to start to change on the gauge, no doubt due to the cold air.

[glavey]

I think I discovered the cause (or at least a contributor) to the erratic tach needle readings. I hooked up my o-scope to the power rail of the arduino while it was running and found, as I suspected, a noisy power supply rail.

I tried adding decoupling capacitors of different ratings from 100µF to 1000µF. They all helped, but none solved the problem completely. Then I discovered that whenever there was an erroneous reading that made the servo move completely to one of its limits, the power LED on the arduino and on the hall effect sensor dimmed. Sometimes the arduino even reset itself.

This clued me in to the hypothesis that the power supply on the arduino board is not capable of supplying enough current to drive the servo and maintain a clean voltage rail.

I am going to try to power both the arduino and the servo from a separate voltage regulator with the servo drawing power directly from the separate regulator, and not the one on the arduino board.


On a different note, I went put on another ride today to pick up some medicine. The scooter performed admirably; no stalls, no (unanticipated) bogs.

I'm starting to think that I want to move the temperature probe for the oil cooler to a place before the radiator, that way I know it is actually having an effect on the oil temperature. As it is now, it is just telling me the the oil that has gone through the radiator has been cooled.

[richardv]

While I can only slightly understand the electronics I'll just listen. But with the oil cooler experiment, wouldn't you want to know both ingoing temp and outgoing temp to compare and maybe even an oil sump temp. You would get more information that way.