torque needed to move a vehicle

[Camillo60]

Good morning to all,
The subject has already been dealt with, however, not having solid bases of mechanical engineering I would like to go back on it to try to understand better what are the necessary steps in order to reach a solution that can be useful also to those who have difficulties.
this the question and the parameters at the moment available:
I have to gear a moving vehicle with 4 full rubber tires rotating on bearings. the flooring is rough concrete. the mass of the vehicle is 6000kg.
under certain circumstances, the vehicle will have to take a road with a gradient of 15°. the speed of the vehicle is not critical and can be set at only 0.5m/min. absolutely non-critical acceleration given the modest speed. a three-phase motor asynchronous + reducer all coupled to one tire (we prevent traction problems in case of poor adherence of the only "active" tire).
I would ask, if possible, to list the stages for the calculation of the various parameters and the relative formulas (simplified where available).
Thank you and I remain available to any questions.
greetings
Camillus

 

[Camillo60]

of course, if not clear, the question is aimed at calculating the torque/power necessary to the wheel to put in gear the medium

 

[DoctorBomber90]

Do you know the vehicle step? that is the distance between the motor axis and the axis of the two non-motor wheels? I would also consider acceleration, to estimate the inertia force of the vehicle (although the speed is low). However, if the value of acceleration is not available, the same is fine.

 

[Camillo60]

exactly 2 meters

 

[Stan9411]

If you neglect the inertia and efficiency of the cinematic chain, the balance pair will be the classic:

(c)

where g is gravity, m the mass of the vehicle, r_ruote the radius of the wheel, tau the transmission ratio from motor to wheel, the slope and mu the coefficient of friction turning between wheel and ground.

However, depending on the type of reducer you may have to add a 10-15% inefficiency, plus any overload data from the ground or from dirt conditions etc etc.

and I will tell you that the acceleration doesn't hurt to consider it .. 6000 kg, even if you want to put a second to get to 0.5 m/s, are 3000n more to add to the calculation.

 

[Camillo60]

thanks stan9411, what unit of measure to adopt?
Could you call me the "balance pair"? Is it enough to march the vehicle?

 

[Stan9411]

the ones that make you return the nm ..
mass in kg
radius in meters
g m/s^2
theta .. depends how you set the calculator degrees or radiants

 

[meccanicamg]

Of course, if you look at the various posts we've done on track carts, you'll find the theory and a real excel.
I do not understand why we have to have more discussion with the same theme.
In addition to the usual formulas we have calculated, we need to disassemble the weight force of the carriage on the inclined plane to see how much the main reaction increases.
It is good not to have engineering bases, but at least the units of measurement should have an idea....multipli or submultipli.

 

[Camillo60]

Sure. You are right, however, the posts I have read on the subject remain orphans of investigation and this door, for those who like me have difficulty, not to understand whether or not it is right.
to be clearer, I find posts where the data subject lists his calculations and formulas. the following answers are almost always "a new" start with new formulas and solution and so on. I do not understand why it is not said, if the original ones of the interested party were correct or not.
Let's understand, it's my limit, but it doesn't help me.

 

[Camillo60]

now I am slaughtered
inserting the values in the above formula comes out a number "monsters" and I certainly made some mistakes
c= 6000 x 9.81 x 0.3 x 100...... already here... is very high

 

[Stan9411]

I suppose 0.3 is the wheel radius
100 will be the transmission report. but the equation I wrote to you describes the balance reported to the engine axis not to the wheel.
in practice the tau I wrote to you is what satisfies the equation:

w_ruota = tau*w_motor

As I suppose it is a classic reducer (of those that reduces speed and increases the torque), tau will be a fraction .. if the value 100 you wrote before , then it will be 1/100

Also you have to put on the tilt part that does a nice mitigation job... for now you are dimensionaling the engine of an elevator

 

[Camillo60]

Okay, I suspect the report should be a fraction.
Now, if for the inclination I use the degrees the effect "mitigation" is much less than using radiants. I do not think I can use one or the other to please (the result is different) so what the correct one?
I know to ask trivial questions, but I do it for those who need it. Thank you.

 

[Stan9411]

Now, if for the inclination I use the degrees the effect "mitigation" is much less than using radiants.

but you understand that this is an unacceptable observation... If you're an engineer, a diplomat or a vessel sergeant

the little thing of an angle always the same number must do, regardless if this angle is expressed in degrees or radiant ... you must set the calculator to receive the angle in degrees or radiant

if you write what(90) and you get 0, it means it is set in degrees
... but here we are at the third media

 

[Camillo60]

you are very rude

 

[Stan9411]

If you neglect the inertia and efficiency of the cinematic chain, the balance pair will be the classic:

(c)

where g is gravity, m the mass of the vehicle, r_ruote the radius of the wheel, tau the transmission ratio from motor to wheel, the slope and mu the coefficient of friction turning between wheel and ground.

However, depending on the type of reducer you may have to add a 10-15% inefficiency, plus any overload data from the ground or from dirt conditions etc etc.

and I will tell you that the acceleration doesn't hurt to consider it .. 6000 kg, even if you want to put a second to get to 0.5 m/s, are 3000n more to add to the calculation.

the ones that make you return the nm ..
mass in kg
radius in meters
g m/s^2
theta .. depends how you set the calculator degrees or radiants

I suppose 0.3 is the wheel radius
100 will be the transmission report. but the equation I wrote to you describes the balance reported to the engine axis not to the wheel.
in practice the tau I wrote to you is what satisfies the equation:

w_ruota = tau*w_motor

As I suppose it is a classic reducer (of those that reduces speed and increases the torque), tau will be a fraction .. if the value 100 you wrote before , then it will be 1/100

Also you have to put on the tilt part that does a nice mitigation job... for now you are dimensionaling the engine of an elevator

I don't know.

 

[Camillo60]

see, the problem of forums is often this. Now you will get a bagarr and no one will have satisfied your desire to know and more will remain this post, like a stain, on this site. a post Monk, meaningless. I'm not a mechanic but I take care of other sector where I think I have skills and if someone tries to understand and/or asks stupid questions I don't allow me to answer them as you did but I try to help him or the limit I tell him I don't have time.
you will also be a great professional but you do not understand that your behavior is deleterious for the good functioning of a place like this which is made by "pochi" assidui "residenti" like you and many "passants" of every order and degree in search of answers sometimes also silly , perhaps from third media.
However, I thank you for the first part of the support before you left the spot....

 

[MassiVonWeizen]

Sure. You are right, however, the posts I have read on the subject remain orphans of investigation and this door, for those who like me have difficulty, not to understand whether or not it is right.
to be clearer, I find posts where the data subject lists his calculations and formulas. the following answers are almost always "a new" start with new formulas and solution and so on. I do not understand why it is not said, if the original ones of the interested party were correct or not.

really is the applicant who has to say if the treatment provided to him was useful to solve/clarify the problem, and it is always the applicant who give a critical feedback so that if he asks tips on heat treatment of a chain crown in the end should report his results.
Unfortunately most of you applicants are limited to likes, some thanks and little more. sometimes, often, not even give a worthy closure to the discussion.

 

[Camillo60]

Massivonweizen, you also have your share of reason. You were able to see the above as unfortunately the discussion was closed and certainly not because of me. humility is a great thing if you ask but not all have this gift. a small massive note, that you say long about what just said.

 

[Stan9411]

I'm even a scourge of humility. . ?

I certainly added a comment that may have shocked you, but also In the last answer I indicated how to move forward in your work.
practice ... what(90) does 0? ok you have to put the angle in degrees in the calculator, otherwise you have to change the option in radiants.

It's easy to say "but I don't know anything, you have to explain everything from the a-b-c and you don't have to yell" .. is the attitude of those who use the forum in the style of the beverage distributor.
even if in life you make the painter, thinking about 1 minute instead of going back to writing, you should have come to mind that the little thing of a corner in degrees or radiant has to do the same number. .
i.e. at least if you decide to embark on the sizing of a motorized carriage!

I'll be wrong.

However, as you say, just with non-technical comments.

 

[MassiVonWeizen]

Massivonweizen, you also have your share of reason. You were able to see the above as unfortunately the discussion was closed and certainly not because of me. humility is a great thing if you ask but not all have this gift. a small massive note, that you say long about what just said.

I don't agree.
first of all you have never written what your skills are and therefore considered the type of forum certain things, except for clarification, are given for granted.
then the discussion is closing you, in fact @stan9411 He didn't write that he won't answer you anymore, but he just showed you how you didn't miss explanations. Besides there is not only he who can answer.. . .
so far your skills have kept them tight and you have not shared anything except these questions that should, through the answers received, be useful to others.