Calculate DC Motor Performance

[Clyde38]

This is a simple spreadsheet to calculate DC motor performance from easily determined values:
Applied Voltage
Resistance
No-Load Speed
No-Load Current

The spreadsheet is protected without a password.

 

[PNachtwey]

Combine your information with this

http://www.engin.umich.edu/group/ctm/examples/motor2/motor.html

and you should be able to estimate dynamic response.

Go to the bottom of the CTM web page and you can see other examples of interest.

Spreadsheets are a good start but you should consider using some public domain math package. Scilab, a public domain version of Matlab, comes to mind. Scilab is OK for small example programs like what you would see here.

clear;                                  // Clear all variables
Distance=2.5;                           // Distance to move
Time=0.3;                               // Time to move the distance
Vel=1.5*Distance/Time                   // Calculate and print the constant velocity
Acc=4.5*Distance/Time^2                 // Calculate and print the acceleration rate
t0=0;                                   // Initial time
t1=Time/3;                              // Time when acceleration ends and constant velocities begins
t2=Time*2/3;                            // Time when constant velocity ends and deceleration begins
t3=Time;                                // Time when deceleration ends and the actuator is stopped
tn=Time+0.1;                            // Time when plot ends
N=(tn/0.01)+1;                          // Number of data point spaced 0.01 second apart
t01=t1-t0;                              // Acceleration time
t12=t2-t1;                              // Constant velocity time
t23=t3-t2;                              // Deceleration time
x0=0;                                   // Initial position
v0=0;                                   // Initial velocity
a0=Acc;                                 // Initial acceleratoin
x1=x0+v0*t01+0.5*Acc*t01^2;             // Position after accelerating
v1=v0+a0*t01;                           // Velocity after accelerating
a1=0;                                   // Acceleration is 0 at constant velocity
x2=x1+v1*t12;                           // Position after constant velocity and before decelerating
v2=v1;                                  // Velocity after constant velocity and before decelerating
a2=-Acc;                                // Acceleration is negative while decelerating
x3=Distance;                            // Final position
v3=0;                                   // Final velocity

tv=linspace(t0,tn,N);                   // Time vector, N time points spaced 0.01 seconds apart

// Calculate the Motion Profile
for n=1:N;
  t = tv(n);                            // get the time for this period
  if t0<=t & t<t1 then                  // Accelerating
    t=t-t0;
    pos(n) = x0+v0*t+0.5*a0*t^2;
    vel(n) = v0+a0*t;
  elseif t1<=t & t<t2 then              // Constant Velocity
    t=t-t1;
    pos(n) = x1+v1*t;
    vel(n) = v1;
  elseif t2<=t & t<t3 then              // Decelerating
    t=t-t2;   
    pos(n)= x2+v2*t+0.5*a2*t^2;
    vel(n)= v2+a2*t;
  elseif t3<=t then                     // Stopped when done
    t=t-t3;
    pos(n)=x3;
    vel(n)=0;
  end
end

// Plot the Motion Profile
clf();                                  // Clear or reset the current graphics figure
subplot(2,1,1);                         // Position plot
plot2d(tv,pos);
xtitle('Position Profile','Time In Seconds','Position');
// legend("Position");

subplot(2,1,2);                         // Velocity plot
plot2d(tv,vel);
xtitle('Velocity Profile','Time In Seconds','Velocity');
// legend("Velocity");

Just copy, paste and execute. Don't copy the

lines if they show.
This implements the motion equations I submitted on another post.

 

[Clyde38]

PNachtwey,
Thanks for the interesting information (Controls Tutorial).

[link

http://www.linkedin.com/in/clydehancock

]

[/url]