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So I need to make choose a motor for my school project. I chose Warp 11-HV, one in the front one in the back. My professor wants me to calculate max speed, acceleration and elevation it can do but I was supposed to do subframe not this. Can someone help me to get to these numbers? It is supposed to by autonomous minibus which weights around 4 tons. It uses 16 inch rims with 225/75 tire(Kormoran VanPro B2 ). 5000 max rpm, 58HP at 1442rpm 72volts.
I also should make the gearing and my goal for max speed is only around 30km/h. I would really appreciate som help as this has nothing to do with what I signed up for...
 

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You have lots of values... how about posting what you think the calculations should be, and what parts you are having issues with, so we can help? I think you'll find most members of this forum are not interested in doing your project for you, and you won't learn anything from that anyway.
 

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Is that power supposed to be the total output for both motors? At 1442 rpm and 72 volts one of these motors uses about 58 HP of electrical power but does not produce anything close to that in output power.

That is for one motor.
The thing is.. I didnt sign up for this, I am supposed to make a 3D model of subframe and test lower arm of doublewishbone suspension in ANSYS. I have no idea how exactly electro motors work with volts and ampers and all that electrical stuff.

I used rpm to get Fk(Mm*is*ni/r and rpm to get speed(2⋅π⋅r⋅nm)/(60⋅is ). Then used speed and weight for resistence of the air and from tires rolling. So after I double the Fk (cause two motors) if it is higher then those two resistances together the vehicle is able to keep the speed without slowing down. But I only have values of torque and rpm for 72 volts and the motor can handle around 200. Also my is=6 as I want it to be a direct drive with max speed around 35km/h so the conversion should be pretty high. But I dont know how the figures will change with more voltage... I guess more voltage more torque but I cant find any numbers to count with. I would like to look at it definetly in the future but I dont have time to understand enough about electric motor in one month when I still need to finnish the actuall model. Professor sent me the email today btw it was never brought up before thats why I am stressing so much about it.
 

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Is that power supposed to be the total output for both motors? At 1442 rpm and 72 volts one of these motors uses about 58 HP of electrical power but does not produce anything close to that in output power.
That is for one motor.
Okay... if you look at the chart of performance data from that NetGain page, you'll see that 58 HP is electrical power input (simply equal to voltage multiplied by current, since this is a DC situation), and that the mechanical power produced in the same conditions (the specific speed at which maximum power was produced in the test) is much lower, due to the inefficiency of the motor. The value from the last line of the performance data chart, with explanations:
speed: 1286 rpm
torque: 172.8 lb-ft
voltage: 72.0 V
current: 597.3 A
input power: 72.0 V * 597.3 A / 746 W/HP = 57.6 HP
output power: 172.8 * 1286 RPM / 5252 = 42.3 HP
efficiency: 42.3 / 57.6 = 73.4%​

At any other speed (and this voltage) the available power is lower. In a road vehicle you would use higher engine speeds, with higher voltage to make that possible.

I used rpm to get Fk(Mm*is*ni/r and rpm to get speed(2⋅π⋅r⋅nm)/(60⋅is ). Then used speed and weight for resistence of the air and from tires rolling. So after I double the Fk (cause two motors) if it is higher then those two resistances together the vehicle is able to keep the speed without slowing down.
I think I see where you're going, but it would be easier if you defined your symbols... for instance, "Mm" might be motor moment (torque), but there is no consistent symbol for most physical quantities.

You can't use a constant motor output torque, because it isn't constant with speed unless something is limiting the motor current to a constant value. If you assume the peak torque and solve for the gearing required, you will likely find that the gearing is too "tall" (insufficient reduction ratio) for acceptable performance at lower speed.

You also can't plan a successful vehicle based on the motor barely being able to keep the vehicle moving at the desired maximum speed, because it won't have enough power to accelerate (add kinetic energy) as well... and you need to accelerate up to that maximum speed.

But I only have values of torque and rpm for 72 volts and the motor can handle around 200. Also my is=6 as I want it to be a direct drive with max speed around 35km/h so the conversion should be pretty high. But I dont know how the figures will change with more voltage... I guess more voltage more torque but I cant find any numbers to count with.
It's worth taking an hour or so to read about some basic motor principles.

For any type of motor, the torque depends on the current (not directly the voltage), because current (multiplied by winding turns) is the magnetic flux in a winding, and flux interaction is force, and force at the pole faces multiplied by the radius to the pole faces is torque. In a series-wound motor like these NetGains, the same current is going through both the rotor windings and the stator windings, so torque climbs more rapidly than directly proportional to currentl.

In the WarP 11HV data the motor produces 172.8 lb-ft of torque with 597.3 A of current... and it will essentially do that at any reasonable speed, if you can apply enough voltage to make that much current flow.

In a motor, voltage is required to overcome the resistance in the windings, plus the back electromotive force (EMF) induced by moving the rotor coil through the stator's magnetic field (or vice versa). That back EMF is proportional speed, and it is the dominant need for voltage, so in general terms more voltage enables the motor to operate at higher speed.

Motors like those from NetGain were designed to run industrial equipment continuously at low speed and power, and are intended for relatively low voltage. In road-going electric vehicles they are normally supplied with higher voltage (allowing higher speed and so more power), and that's acceptable because they don't run at full power all of the time, so they don't overheat. If you were to plan to use full rated power to keep the vehicle moving (which would be a mistake), you wouldn't be able to run the motor at much higher than rated power because it will overheat. NetGain and similar suppliers usually don't provide test data for voltages as high as many people will use, but a lack of good objective data is not surprising for these low-budget and low-tech operations.
 

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The thing is.. I didnt sign up for this, I am supposed to make a 3D model of subframe and test lower arm of doublewishbone suspension in ANSYS. I have no idea how exactly electro motors work with volts and ampers and all that electrical stuff.
...
I would like to look at it definetly in the future but I dont have time to understand enough about electric motor in one month when I still need to finnish the actuall model. Professor sent me the email today btw it was never brought up before thats why I am stressing so much about it.
Welcome to a small taste of the real world, in which things don't always go the way you would like, and there is no one else to do your job for you. Don't panic - whatever point you are at in your education, if you are making 3D structural models and being asked to size drive components, you must have the fundamental understanding on which you can build the required knowledge. I'm talking about an evening, not a month of study.
 

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"It's not my job" or "I didn't sign up for this" won't get you very far. Especially in industry, even more critical in a startup where you wind up doing the dishes, literally, at times. If you are in engineering, you are expected to research the problem and its constraints, which includes going outside your comfort zone. Lecture over

While playtime in the ANSYS sandbox is neat stuff, all those pretty colors, there's a reason your prof asked you to do the calcs. There's always a reason your boss asks you to do stuff - you didn't ask why, you didn't push back, just got whiny and went off to places on the net to have people do it for you. Nuh uh. That's not research, that's not learning the methods and basics. That's not design or engineering.

How on earth are you supposed to design an A-arm if you have't calculated the applied dynamic loads? Go up a hill, or go into a pothole, and the thing snaps...not pretty at 4 tons. All because you did a static analysis.

The tool is only as good as the person using it. I've seen the wrong loading applied to a generative design (look on Youtube at Thomas Sanladerer designing a bookshelf bracket), which comes up with the totally wrong solution. You have to be savvy enough to question your results, despite the assumed infallibility of the FEA software.
 
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