/diy/ - Do It Yourself

>>624278
nice

>>625001
he's probably a drop out

>>624077
>Stop liking things I don't like!
>>>/b/

>>623685
>>623706
>>>/b/

>>623729
1/2 ton of imitation crab meat in a shipping container

Light the fuse
Walk away

>>623411
GPS has shit accuracy for measuring altitude

>>623278
This is really good advice. I'm a current Engineering student.

>>623344
what's your major?
This is baby stuff.

>>623348
what is perf board?

>>623370
this is good advice, though GPS is pretty shit for elevation data

You want an altimeter. I'm sure someone has already gone throught the hassle of creating the library for a relatively cheap one if you want to connect it to arduino.

found this after 3 minute with google:
http://www.apogeerockets.com/Electronics_Payloads/Electronics/Jolly_Logic_AltimeterTwo

Since you were too lazy to do the search yourself, i'm sure you'd rather take the lazy option like this.

>>623391
you're a fuggin idiot

>>622634
A licence from the FCC

>>619462
ozone is bad for your health

http://www.epa.gov/groundlevelozone/health.html

>>618053
faggot

>>617820
ohh fug, nostalgia'd hard

>>617086
no you

>>617772
This thred is fucking stupid. Let it die already.

>>617115
>>>/x/

>>616776
why not use a shipping container?

>>616650
Who are you quoting?

Just from eyeballing I would guess that belt drive is about 90% efficient for your application.

Choosing the optimal motor is outside my knowledge base.

Are you trying to hit some efficiency mark? Because you're going to have an extremely difficult time getting a total system efficiency better than 2-3% with all the steps you're using. This isn't a bad thing. Just getting everything assembled and working is pretty impressive. Cool project.

What exactly are you trying to achieve at this point?

>>616627
>i am using PWM but always have to hit full power to let it drive, otherwise it just makes this high pitched noise in the motor.
In that case you are probably getting close to the rated efficiency.

>but belt drives are 98% efficient according to wiki
No. That one style of highly engineered belt drive is 98% efficient. Unless your belt drive is appropriately sized and very well constructed I doubt you're a getting better than 90%.

What do you mean by 'perfect torque'?

>>616494
If he's as dumb as you, you could probably convince him that he drank your pee.

>>616232
You're assuming the difference in efficiency is entirely in the motor.

>>616409
Its not that your torque Is wrong, its that your motor may not be under ideal loading, so you're getting less than the rated efficiency. It depends on the type of motor and motor controller you're using. If you use pulse with modulation ( pwm) you can increase the efficiency vs hitting the motor with pure direct current. You'd have to ask an electronic s guy for more detail.

I suspect you're losing a bit of energy transmitting power from the motor to the drive shaft. Gear trains are typically better than 95% efficient, but belt drives are notoriously lossy. If you're using a stiff belt over small pullies you could easily be losing 50% of the motor output power.

>>616409
torque=force*distance [see pic]

Your numbers are all reasonable.

There is always a difference between theoretical and experimental.

Theoretical Efficiency = product of all the component efficiencies

Expirimental = work done / energy in

This is a very important concept to understand.

>>616370
2deep4me

Are you trying to make some kind of point?

>>616378
my sides will never be the same

>>616347
And the dish ran away with the spoon.