Go Down

### Topic: Motor design (Read 159 times)previous topic - next topic

#### nate5678

##### Mar 21, 2019, 10:24 pmLast Edit: Mar 21, 2019, 10:30 pm by nate5678
Hello,
I need a motor for my project. My aim is to move a 10 kg mass using a belt pulley system, with a velocity of 15km/hr to a distance of 3.6m. The maximum time for moving the same is 1.5 sec.

Can somebody please help me with the calculation and finding out the right motor, that is the max power and max.rpm of the motor required

#### hammy

#1
##### Mar 22, 2019, 09:48 am
You first need to sort out the mechanical design of how you are going to do this .
As you are accelerating the ( heavy) weight , and have a short time period , then I'm guessing this is going to be a substantial motor drive , with reduction gearing .
Some maths is going to be needed  to estimate power need as well as the motor characteristic  and probably don't need an Arduino !

A few more details might help readers

#### WattsThat

#2
##### Mar 22, 2019, 03:24 pm
Quote
My aim is to move a 10 kg mass using a belt pulley system, with a velocity of 15km/hr to a distance of 3.6m. The maximum time for moving the same is 1.5 sec.
15km/hr = 15000m/hr = 250m/min = 4.1666m/sec

4.1666m/sec * 3.6m = 15 sec

So why does it need to make the move 10 times faster than that?

You also need to state in what plane/angle the load is moving. Friction can be a large component of the power requirement as well, depending upon the system.
Vacuum tube guy in a solid state world

#### jremington

#3
##### Mar 22, 2019, 04:30 pm
Please post a photo or accurate drawing of the complete belt and pulley system.

#### vinceherman

#4
##### Mar 22, 2019, 05:48 pmLast Edit: Mar 22, 2019, 05:49 pm by vinceherman
15km/hr = 15000m/hr = 250m/min = 4.1666m/sec

4.1666m/sec * 3.6m = 15 sec
I was with you until this.  Could just be lack of caffeine.

I get 15 m^2/sec which is probably not where you were looking to go.

3.6m / (4.1666m/sec) = .864sec
So if the mass is already moving at 15kph then it will take a bit under a second to travel the required distance.  That leaves some room for acceleration.

#### MarkT

#5
##### Mar 22, 2019, 11:01 pmLast Edit: Mar 22, 2019, 11:05 pm by MarkT
15km/hr = 15000m/hr = 250m/min = 4.1666m/sec

4.1666m/sec * 3.6m = 15 sec

So why does it need to make the move 10 times faster than that?

You also need to state in what plane/angle the load is moving. Friction can be a large component of the power requirement as well, depending upon the system.

That makes no sense, you are multiplying a speed by a distance!

distance = 3.6
max velocity = 4.16
max time = 1.5

I reckon an acceleration of about 6.5m/s^2 for 0.65s, then coast at 4.2m/s for 0.2s, then decelerate
at -6.5m/s^2 for 0.65s will get you there just in time with minimal acceleration.  I assume the mass
should stop at the end of travel.

The force need to accelerate 10kg at 6.5m/s^2 is 65N, so the max power required is this force
times the max speed, ie 4.2 x 65 = 270W.

Without geometry of the pulley there is no way to say anything about rpm or gearing requirements.

10kg travelling at 4.2m/s sounds pretty dangerous BTW, think sledge hammer.  The kinetic
energy is 90J or so
[ I will NOT respond to personal messages, I WILL delete them, use the forum please ]

#### hammy

#6
##### Mar 23, 2019, 08:41 am
I would question why you want to do this ? What is the project?

Go Up