Search results

You could write a counter to the eeprom that indicated how many times it has been run and that is reset somehow when u charge it back up. Maybe a certain button combo.

What I would do for the constants is try to figure out what output you want when the temp just barely drops below the set point. If you are oscillating above that means P is too high probably. Also, you may not even need derivative. I would try taking it out entirely and testing. It improved...

If the stability erodes I would say you probably have too low integral gain. The integral is what "eliminates" (theoretically) the steady state error. The errors close to the set point are near zero, and if there was much overshoot or oscillations above the set point, then a lot of the...

Too bad. What happened to the 1F swing? I just rewrote my display code today to include 3 modes: 1 While heating a progress bar T:XXXXXXS:XXXXXX @@@@@@@ | 2 When in range of set point T:XXXXXXS:XXXXXX Wait for it.... 3 After it's been at set point for a while and the vapor is...

What PID constants are you using now?

Wow. That is truly strange, because the manufacturer rates them as operating fine down to -40C.

My plan was to usea burr bit to put a divot, then a twist bit to actually drill through. I have access to mill, press, dremel, more tools than I can find uses for. I've already drilled the holes a few times through the mason jars I use as housing. It worked good in a drill press. Didn't...

For me the vapor residue goes up about 2/3'rds of the tube, but I use the small diameter tube. With paper towels you can't get stoned. I guess a long thin knife would be pretty much the best thing. I tried using my bowl grabbing tweezers, but that just gets oily vapor residue all over...

I wish there was a good tool for scraping down the insides of the vapor tube. Some vapor condensate gets trapped above where it gets hot if I just try to stick the tube straight into the vape. Right now to get rid of it I just use a lighter and hit it like a crack pipe.

Does your voltage regulator fail stopping further discharge before it reaches the critical point, or do you just monitor the battery voltage yourself?

Ordered some Blue Lipo batteries. They aren't the nice LiFePO4 like the A123's but they cost about half as much. I got a 7.4V 3300mAh for long hauls and a 1300mAh for quick sessions. I hope to set up a dock that the vape can sit in at home and charge the battery.

I do infact use an oscilloscope. Way better idea though, is output duty cycle to screen. I don't have time right now. And try a different browser if the vids don't work. Works fine in chrome.

The 1 degree is in celcius though, so its really 2.2F. What is the resolution of your PWM control? My compiler has 8bits (0-255), but I could set it to 10 bits (0-1023) if I thought I needed to. I'm not sure what values it usually puts out, but I would probably guess it turns on about 1/4 to...

Really? The vids work fine for me. In the video the setpoint is 200, the max it reaches is 201.25 and minimum is 199.50, but mostly it stays between 200 and 201. I could probably fine tune better, but I got a bunch of stuff going on a school, so I'll probably wait until I have a 2nd prototype to...

I took some crappy vids of my vape in action. Here is the steady state oscilations of the controller http://img46.imageshack.us/img46/8702/video9272.mp4 Heating http://img46.imageshack.us/img46/7594/video3057.mp4 Hitting http://img46.imageshack.us/img46/1598/video9272j.mp4 For me there is...

$500 is a little absurd. The batteries may be $100 after you get the pack and charger, but the other costs are very low. I have 3 clones (with my algorithm, just same LED indicators) of your vape and 9 of mine (LCD readout). Of course mine run off of old comp power supplies and not nice...

Nice. Have you measured the overall dimensions with the components in place?

starting to hit it success

Click the link to see the big pic. The gear The screen (from dead on the screen is crisper.) the transistor (kinda blurry) connecting to the power supply with molex empty tube bowl inserted vapor starting to show up at the connection

It all works beautifully, and I didn't even need to modify anything to get ICSP to work. I clocked the heating time at 28s. I need to tune the algorithm better though, because it overshoots by 10C then each time it dips under the setpoint it jumps over by 5C slightly decreasing each time. It...