how to choose motor?

[electricano]

hello.i just want to know how to choose a motor for my project
my project is a car, weighted about 6kg.the car should have minimum speed at about 5km/h and is able to accelerate at speed 10km/h for certain period only. it must be a dc motor
what critieria chould i consider?

 

[windozeuser]

LOL I did this a long time ago but know i forget now :x I Might Remember After Thanksgiving Dinner Lol but i still remember some stuff like

one horsepower = 746 watts

(electric motor's can be measured in watts and horsepower)

one horse power = 33,000 foot-pound's of work in one minute

speed = distance / time
work = force * distance
power = work / time

weight is a type of force so the weight of the car would be the force

sorry i cant remember any more stuff like how to find horsepower i know its simple but i forget!!!! :cry: but this should help a little, TIME TO GET MY TECH BOOKS OUT!!!

 

[windozeuser]

This Info Is For A Car That Is Like The Size Of A Computer Tower Horizontal lol but in your case u need to go smaller than this. It Depend's on the size and weight of the car, Electric Motor's Can Get Pretty Big

You Should Consider The Rpm Of The Motor

More Rpm = More Speed, Less Torque
Less Rpm = Less Speed, More Torque

In This Case i think a motor between 3200 to 3800 rpm is good (Dont Know For Sure)

Probably Get A Motor From 1 Horse Power To 3 Horsepower
or 746 to 2238 watts

Plus u need the gear Ratio Right To Get The Right Speed And Torque Of The Car

www.howstuffworks.com has some articles of gear ratio and other helpful and interesting stuff!

lol i should try to build a battle bot!!!

 

[Russlk]

How steep an incline does the vehicle have to climb? On the level, the motor size is only constrained by the friction. How fast does it have to accelerate? A toy car motor would be too small, but a motor from a kid's ride on toy might work. Automobiles use small, powerfull motors to raise windows, move seats, etc.