DC Voltage question

[Canker_Canison]

I'm working on a project that I shelved some years ago.

Changed the design as new DC motors are now available. But my head refuses to work when looking at the voltage required.

5 x 3V DC motors to be powered in parallel to allow vairiable control on each motor. (Rated at 2.4V - 3.6V)

My head is refusing to let me see sense.

Will I need a power source with a 3V DC output with high mAh?

Or should I be looking at 12V DC output.

Looking at running on either CR2032 3V, AAA 1.5V or AA 1.5V batteries. Weight & size is important (the smaller the better), but so is the available ampage.

Another power option would be a mobile phone battery. Li-ion 3.4V

But will I get max revs on all 5 motors if using a single 3V supply?

[TheCoder]

If the motors are in parallel, then your psu needs to supply the motor voltage (ie 3V). The mA of your psu will obviously need to be sufficient to run all motors under full load (ie, if they are rated 200mA each under full operational torque then you'll need a psu capable of at least 1 amp but you should probably allow around 50% extra (so 1.5A) )

Depending on what your doing, i'd suggest maybe you use a 12v power supply with a local 3v dc-dc converter on each motor. Done properly this would maximise the use as the batteries become 'flat'

[Meat-Head]

no idea what your doing, but chances are what ever it is, it's going to 'fly' guess motors will run at 10,00,000,000000,,,,00000 (beat that SJ) RPM

a cell phone battery would be 'best'

look on ebay for speed controlers.

if you have millions, go search think QED controllers, make you what you want.

[super jumbe]

So you are working on a project then you changed the method of design could you change the project again and build a monster?..

[fes_786]

He's making a drone to spy on the girl next door....pmsl

I would go with the 12v battery and a small dc - dc converter will b best if u going to mount a wireless camera

[Meat-Head]

I would go with the 12v battery and a small dc - dc converter will b best if u going to mount a wireless camera

*WHY*

The word inefficent springs to mind, like having a dawg and barking yourself.

If your doing that 12volt and 12volt motor.

Can you download off ebay a wang-foo helecopter.

motors and battery, speed controller all ready to go.

look at the FET - see if it's good enough for 5 motors - stall currant?

[Canker_Canison]

no idea what your doing, but chances are what ever it is, it's going to 'fly' .

It's not going to fly...

He's making a drone to spy on the girl next door....pmsl

That would be the three college students over the road.

But I'm not making one of these....

[ame=http://www.youtube.com/watch?v=GcpHA-U4-XA]Tricopter running MultiWii code, aggressive settings - YouTube[/ame]

If I was I'd be picking my dad's brains.


What I'm making will bring pleasure to some, but it also needs to be water tight.

I'm going to wait until I get my new motors before I start playing. As per usual I'll be using the trial & error approach to see what works best.

Once the prototype is made & tested I'll be taking orders as you'll all want one

[Mjolinor]

It's not going to fly...

Once the prototype is made & tested I'll be taking orders as you'll all want one

You can buy them already from Amazon

http://www.amazon.com/s?ie=UTF8&keywords=dildo&rh=i%3Aaps%2Ck%3Adildo&page=1

[Meat-Head]

It's not going to fly...

Tricopter running MultiWii code, aggressive settings - YouTube

one

http://www.digital-kaos.co.uk/forums/f86/dead-pet-turned-into-helicopter-275815/

[Canker_Canison]

You can buy them already from Amazon

Amazon.com: dildo

Not like mine you can't

Think of something like this...



Only a lot less bulky, no glove, better motor control & hopefully fully waterproof (kind of important where water sports are concerned).


Thinking of starting with a straight 6V DC & going from there.

Just checked one of the original motors with two CR2032 batteries in series... nice pick up in rpm. Just have to ensure they don't burn out when covered in latex.

[TheCoder]

Just checked one of the original motors with two CR2032 batteries in series... nice pick up in rpm. Just have to ensure they don't burn out when covered in latex.

Measure the current consumption of the motors under your predicted normal and maximum torque loads. Unless they are very small motors with very small torque loads then I doubt a cr2032 type battery pack would drive them for long !

Assuming they are very small then the latex thing shouldn't be a problem. There would be very little heat generated if your only drawing a few mA at 3V. Depending on operational duration you could likely get away with a few hundred milliWatts before heat becomes problematical. If you can get datasheets for the actual motors it may give you info on the thermal dynamics.

[Canker_Canison]

This may not be accurate to what I've ordered from china, but it won't be far off...I hope.

Listed on a UK manufacturer website

Low performance version

Typical power comsumption 156mW
Typical operating current 52mA

Higher performance version

Typical power comsumption 190mW
Typical operating current 63mA


But the pricing is way off what I paid.... about 10 times the price.

[TheCoder]

Those are probably just on the 'edge' for heat production in an enclosed environment so a lot may depend on your duty cycle (ie how long you will drive the motor under high torque) as well as what form of heatsinking you can provide (its amazing how much heat a single piece of mechano can draw) and the actual construction of the motor itself. If its cheap construction it will take far less heat than a more robust construction. Unfortunately, this info is mostly down to a decent datasheet.

Regarding batteries - 50mA is a hell of a draw for CR2032 types where the average requirement would be more apt to be 0.5mA. 50mA is more like an AAA type cell (around 250mAh), so 2*AAA would, in theory, give you enough for 1 hour on 5*50mA 3v motors. In practice you'd more likely get 1/2 that duration so if you want 1 hour you should double up (2 sets of 2*AAA in parallel). If you want longer then you need to go to AA cells (around 600mAh) or larger.

[Meat-Head]

just to add pn the power

ebay type in 3300mah 2.4 jolts ?5 look for ps2 or x box controllers remote battry & charger

[Canker_Canison]

@ Thecoder

The CR2032's are just the easiest thing for me to work with right now.... Got over 20 of the gits kicking around.

I have a 4 x AA battery holder that will take on time at all to convert to 2 x 2 AA in parallel.

Once I get the motors I'll set one in latex & run a time trail.

A second project has come to mind if I can get these working


@ Meaty

I have access to a lot of mobile batteries. But that will mean having to vacum form a battery holder, which is something I'd like to avoid if possible.
The Xbox controller batteries will cause charging problems...as would the mobile batteries.

But I'm stuck until the motors arrive.