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Simple Motor Calculator (http://www.chiefdelphi.com/media/papers/2432?) by Ether
Simple Motor Calculator
I created this small app for my own use, then realized that others might find it interesting/fun/handy.
Constructive criticism and error reports welcome.
Note: for those looking for something more comprehensive, check out JVN's calculator.
http://www.chiefdelphi.com/media/papers/2059
The updated version will allow you to enter a desired motor power, and it will then calculate the rpm range, the torque range, and the current range over which the motor will deliver at least that much power.
Also, if there is some reason why you want to always operate the motor at or above a certain efficiency, you can enter the desired efficiency and it will calculate the rpm range, the torque range, the current range over which the motor will operate at an efficiency equal to or greater than the entered number.
The updated version will allow you to enter a desired motor power, and it will then calculate the rpm range, the torque range, and the current range over which the motor will deliver at least that much power.
Also, if there is some reason why you want to always operate the motor at or above a certain efficiency, you can enter the desired efficiency and it will calculate the rpm range, the torque range, the current range over which the motor will operate at an efficiency equal to or greater than the entered number.
Ether, nice little program and simple to use. great work. As an Engineer, I am always impressed at what people come up with to solve simple problems when the use the theory of "STICK ON A STRING". If you keep this in mind when face with a problem, life will be great and a little less stressful.
Again, Do not stop what it is that you do best, GREAT WORK.:cool:
I have updated the motor calculator (http://www.chiefdelphi.com/media/papers/2432) for the 9015 (am-0912) and PG71 (am-0914) 2012 motors.
The app is now 32-bit so it should now run in 64-bit Windows (XP & 7).
I am re-working the floating-point error trapping and will update again when that is done.
Enjoy.
Floating-point exception handling added.
MCALC32c (http://www.chiefdelphi.com/media/papers/2432).
Works in 32-bit or 64-bit Windows.
Scrollable window.
Includes 9015 (am-0912), PG71 (am-0914), and fc12-20 motors.
For anyone who has downloaded MCALC32, please be advised that the specs for the PG71 gearmotor are in dispute1.
As soon as this is settled, I will update the calculator.
Sorry for any inconvenience.
1 http://www.chiefdelphi.com/forums/showthread.php?t=99488
Motor Calculator build MCALC32g 1/9/2012 350p
Now supports the following motors:
CIM
FP0673
FP2719
FP9012
FP9015
RS395
RS540 (not legal for 2012 but included)
RS550
RS775-12
RS775-18
am-0912
am-0914
DensoL
DensoR
Denso AE235100-0160
Here's a copy-and-paste ticker tape output from the motor calculator. If you disagree with any of the specs please let me know. Thanks:
Motor Calculator build MCALC32h 1/9/2012 643p
CIM FR801 001, AM802 001A @ 12.00 volts:
@ free (no load):
oz-in Nm rpm rpm% amps watts out watts in eff%
0.0 0.000 5310 100.0 2.7 0.0 32.4 0.0
@ stall:
oz-in Nm rpm rpm% amps watts out watts in eff%
343.4 2.425 0 0.0 133.0 0.0 1596.0 0.0
@ max power:
oz-in Nm rpm rpm% amps watts out watts in eff%
171.7 1.212 2655 50.0 67.8 337.1 814.2 41.4
@ max efficiency:
oz-in Nm rpm rpm% amps watts out watts in eff%
42.8 0.302 4648 87.5 18.9 147.1 227.3 64.7
FP 00801-0673 @ 12.00 volts:
@ free (no load):
oz-in Nm rpm rpm% amps watts out watts in eff%
0.0 0.000 20770 100.0 0.8 0.0 9.8 0.0
@ stall:
oz-in Nm rpm rpm% amps watts out watts in eff%
75.4 0.532 0 0.0 108.7 0.0 1304.4 0.0
@ max power:
oz-in Nm rpm rpm% amps watts out watts in eff%
37.7 0.266 10385 50.0 54.8 289.5 657.1 44.1
@ max efficiency:
oz-in Nm rpm rpm% amps watts out watts in eff%
6.0 0.043 19110 92.0 9.4 85.2 113.3 75.2
FP 000968-2719 @ 12.00 volts:
@ free (no load):
oz-in Nm rpm rpm% amps watts out watts in eff%
0.0 0.000 16100 100.0 2.0 0.0 24.0 0.0
@ stall:
oz-in Nm rpm rpm% amps watts out watts in eff%
57.5 0.406 0 0.0 63.0 0.0 756.0 0.0
@ max power:
oz-in Nm rpm rpm% amps watts out watts in eff%
28.8 0.203 8050 50.0 32.5 171.1 390.0 43.9
@ max efficiency:
oz-in Nm rpm rpm% amps watts out watts in eff%
8.7 0.061 13665 84.9 11.2 87.9 134.7 65.2
FP 000968-9012 @ 12.00 volts:
@ free (no load):
oz-in Nm rpm rpm% amps watts out watts in eff%
0.0 0.000 15600 100.0 1.0 0.0 12.0 0.0
@ stall:
oz-in Nm rpm rpm% amps watts out watts in eff%
59.5 0.420 0 0.0 63.5 0.0 762.0 0.0
@ max power:
oz-in Nm rpm rpm% amps watts out watts in eff%
29.8 0.210 7800 50.0 32.3 171.6 387.0 44.3
@ max efficiency:
oz-in Nm rpm rpm% amps watts out watts in eff%
6.6 0.047 13861 88.9 8.0 68.0 95.6 71.1
FP 000968-9015 @ 12.00 volts:
@ free (no load):
oz-in Nm rpm rpm% amps watts out watts in eff%
0.0 0.000 15600 100.0 1.3 0.0 15.0 0.0
@ stall:
oz-in Nm rpm rpm% amps watts out watts in eff%
63.7 0.450 0 0.0 70.0 0.0 840.0 0.0
@ max power:
oz-in Nm rpm rpm% amps watts out watts in eff%
31.9 0.225 7800 50.0 35.6 183.7 427.5 43.0
@ max efficiency:
oz-in Nm rpm rpm% amps watts out watts in eff%
7.5 0.053 13761 88.2 9.4 76.4 112.3 68.1
M3-RS395-12 @ 12.00 volts:
@ free (no load):
oz-in Nm rpm rpm% amps watts out watts in eff%
0.0 0.000 15500 100.0 0.5 0.0 6.0 0.0
@ stall:
oz-in Nm rpm rpm% amps watts out watts in eff%
16.7 0.118 0 0.0 15.0 0.0 180.0 0.0
@ max power:
oz-in Nm rpm rpm% amps watts out watts in eff%
8.3 0.059 7750 50.0 7.8 47.8 93.0 51.3
@ max efficiency:
oz-in Nm rpm rpm% amps watts out watts in eff%
2.6 0.018 13107 84.6 2.7 24.9 32.9 75.9
***NOTE*** RS540 is not legal for 2012
RS540 @ 12.00 volts:
@ free (no load):
oz-in Nm rpm rpm% amps watts out watts in eff%
0.0 0.000 17200 100.0 0.9 0.0 11.2 0.0
@ stall:
oz-in Nm rpm rpm% amps watts out watts in eff%
32.6 0.230 0 0.0 36.8 0.0 441.6 0.0
@ max power:
oz-in Nm rpm rpm% amps watts out watts in eff%
16.3 0.115 8600 50.0 18.9 103.8 226.4 45.8
@ max efficiency:
oz-in Nm rpm rpm% amps watts out watts in eff%
4.5 0.032 14841 86.3 5.8 49.1 70.2 70.0
RS550 stall torque changed to 70.5 oz-in per 2012 FRC specs
M5-RS550-12 (-B) @ 12.00 volts:
@ free (no load):
oz-in Nm rpm rpm% amps watts out watts in eff%
0.0 0.000 19300 100.0 1.4 0.0 16.8 0.0
@ stall:
oz-in Nm rpm rpm% amps watts out watts in eff%
70.5 0.498 0 0.0 85.0 0.0 1020.0 0.0
@ max power:
oz-in Nm rpm rpm% amps watts out watts in eff%
35.3 0.249 9650 50.0 43.2 251.5 518.4 48.5
@ max efficiency:
oz-in Nm rpm rpm% amps watts out watts in eff%
8.0 0.057 17105 88.6 10.9 101.4 130.9 77.5
M7-RS775-12 @ 12.00 volts:
@ free (no load):
oz-in Nm rpm rpm% amps watts out watts in eff%
0.0 0.000 7300 100.0 1.1 0.0 13.2 0.0
@ stall:
oz-in Nm rpm rpm% amps watts out watts in eff%
61.1 0.431 0 0.0 30.0 0.0 360.0 0.0
@ max power:
oz-in Nm rpm rpm% amps watts out watts in eff%
30.6 0.216 3650 50.0 15.6 82.5 186.6 44.2
@ max efficiency:
oz-in Nm rpm rpm% amps watts out watts in eff%
9.8 0.069 6127 83.9 5.7 44.5 68.9 64.5
M7-RS775-18 @ 12.00 volts:
@ free (no load):
oz-in Nm rpm rpm% amps watts out watts in eff%
0.0 0.000 13000 100.0 1.8 0.0 21.6 0.0
@ stall:
oz-in Nm rpm rpm% amps watts out watts in eff%
112.8 0.797 0 0.0 86.7 0.0 1040.4 0.0
@ max power:
oz-in Nm rpm rpm% amps watts out watts in eff%
56.4 0.398 6500 50.0 44.3 271.2 531.0 51.1
@ max efficiency:
oz-in Nm rpm rpm% amps watts out watts in eff%
14.2 0.100 11363 87.4 12.5 119.4 149.9 79.7
am-0912 (CCL 9015) @ 12.00 volts:
@ free (no load):
oz-in Nm rpm rpm% amps watts out watts in eff%
0.0 0.000 16000 100.0 1.2 0.0 14.4 0.0
@ stall:
oz-in Nm rpm rpm% amps watts out watts in eff%
60.6 0.428 0 0.0 63.8 0.0 765.6 0.0
@ max power:
oz-in Nm rpm rpm% amps watts out watts in eff%
30.3 0.214 8000 50.0 32.5 179.4 390.0 46.0
@ max efficiency:
oz-in Nm rpm rpm% amps watts out watts in eff%
7.3 0.052 14070 87.9 8.8 76.1 105.0 72.5
Specs for am-0914 (PG71) motor are disputed.
Update will be posted when available.
am-0914 (PG71) @ 12.00 volts:
@ free (no load):
oz-in Nm rpm rpm% amps watts out watts in eff%
0.0 0.000 84 100.0 1.3 0.0 15.6 0.0
@ stall:
oz-in Nm rpm rpm% amps watts out watts in eff%
4140.0 29.235 0 0.0 26.8 0.0 321.8 0.0
@ max power:
oz-in Nm rpm rpm% amps watts out watts in eff%
2070.0 14.617 42 50.0 14.1 64.3 168.7 38.1
@ max efficiency:
oz-in Nm rpm rpm% amps watts out watts in eff%
739.3 5.221 69 82.1 5.9 37.7 70.3 53.7
DensoL 262100-3040 @ 12.00 volts:
@ free (no load):
oz-in Nm rpm rpm% amps watts out watts in eff%
0.0 0.000 84 100.0 1.8 0.0 21.6 0.0
@ stall:
oz-in Nm rpm rpm% amps watts out watts in eff%
1501.1 10.600 0 0.0 21.0 0.0 252.0 0.0
@ max power:
oz-in Nm rpm rpm% amps watts out watts in eff%
750.5 5.300 42 50.0 11.4 23.3 136.8 17.0
@ max efficiency:
oz-in Nm rpm rpm% amps watts out watts in eff%
339.5 2.398 65 77.4 6.1 16.3 73.7 22.1
DensoR 262100-3030 @ 12.00 volts:
@ free (no load):
oz-in Nm rpm rpm% amps watts out watts in eff%
0.0 0.000 84 100.0 1.8 0.0 21.6 0.0
@ stall:
oz-in Nm rpm rpm% amps watts out watts in eff%
1501.1 10.600 0 0.0 18.6 0.0 223.2 0.0
@ max power:
oz-in Nm rpm rpm% amps watts out watts in eff%
750.5 5.300 42 50.0 10.2 23.3 122.4 19.0
@ max efficiency:
oz-in Nm rpm rpm% amps watts out watts in eff%
357.4 2.524 64 76.2 5.8 16.9 69.6 24.3
Denso AE235100-0160 @ 12.00 volts:
@ free (no load):
oz-in Nm rpm rpm% amps watts out watts in eff%
0.0 0.000 5300 100.0 1.0 0.0 12.0 0.0
@ stall:
oz-in Nm rpm rpm% amps watts out watts in eff%
18.4 0.130 0 0.0 7.0 0.0 84.0 0.0
@ max power:
oz-in Nm rpm rpm% amps watts out watts in eff%
9.2 0.065 2650 50.0 4.0 18.0 48.0 37.6
@ max efficiency:
oz-in Nm rpm rpm% amps watts out watts in eff%
5.0 0.036 3846 72.6 2.6 14.4 31.8 45.2
I've just been informed (by someone in a position to know) that the "9013" in the KoP Checklist is an error: It should be 9012.
Team Update #2 (2012-01-13) added FP-9012 to [R48] and kept FP-9013.
The motor calculator (http://www.chiefdelphi.com/media/papers/2432) supports the FP-9012. As soon as specs for FP-9013 become available I will add them to the calculator.
The motor calculator (http://www.chiefdelphi.com/media/papers/2432) has been updated with the latest (1/16/2012) lab data for the am-0914 gearmotor.
I decided to incorporate 2 separate sets of motor specs for this gearmotor:
one for brand-new (unused) gearmotor, and
one for used (broken-in) gearmotor
... since the lab data indicated a significant difference.
** ACTUAL GEARMOTOR PERFORMANCE PROBABLY LIES SOMEWHERE BETWEEN **
Links to the 3 lab report PDF documents can be found at the bottom of this (http://www.andymark.com/product-p/am-0914.htm) web page.
If you have even a passing interest in motor testing, you will find this interesting reading.
DOES ANYONE HAVE SPECS FOR THE FISHER-PRICE FP-000968-9013 ???
Motor calculator (http://www.chiefdelphi.com/media/papers/2432) has been updated to MCALC32t and includes:
the just-released specs for the FP-9013 listed in the FRC motor data table (http://www.usfirst.org/sites/default/files/MotorInfo4.1.pdf) as of 1/18/2012 12:30pm
the changed specs for the am-0914 listed in the FRC motor data table (http://www.usfirst.org/sites/default/files/MotorInfo4.1.pdf) as of 1/18/2012 12:30pm
The calculator now gives the user the option to select which specs to use for am-0914, since there are 3 different sets of specs (explained in the am-0914 options menu).
MCALC32w (http://www.chiefdelphi.com/media/papers/2432) fixes a problem with the spec options menu for the am-0914.
MCALC32aa (http://www.chiefdelphi.com/media/papers/2432) adds a UserDefined motor to the motor selection menu.
EDIT: MCALC32ab adds exception handling to user-defined motor input
bmlarson12
27-01-2012, 15:18
WOW!!! How did you do this? I have been looking for a graph of the information so I could get the general values, but this is far better!
WOW!!! How did you do this? I have been looking for a graph of the information so I could get the general values, but this is far better!
If you assume that the speed vs torque and the current vs torque "curves" are straight lines (which is the standard assumption for almost all the motors used in FRC), then most of the equations are fairly straightforward to solve explicitly.
For example, at the rated voltage and for a given torque tau, you can find the speed as follows:
speed = free_speed*(1-tau/stall_tau)
some of the other calculations, for example solving for efficiency or finding voltage when given rpm and torque, are a bit trickier, but not too bad.
I'm glad you discovered it and hope you find it helpful.
wireties
27-01-2012, 16:37
Ether == Awesome - any chance you'll part with the source so I can compile a Linux version?
TIA
Ether == Awesome - any chance you'll part with the source so I can compile a Linux version?
It would be good to have a Linux version.
I'll pull out the formulas and post them.
Give me a couple of days.
wireties
27-01-2012, 19:41
It would be good to have a Linux version.
I'll pull out the formulas and post them.
Give me a couple of days.
If it was a windows console app, it will probably just compile and run quickly with minor changes. You can send the source if you want.
It would be good to have a Linux version.
I'll pull out the formulas and post them.
Give me a couple of days.
Here (http://www.chiefdelphi.com/media/papers/download/3322) ya go.
wireties
30-01-2012, 14:15
Here (http://www.chiefdelphi.com/media/papers/download/3322) ya go.
I'm a busy guy - no time soon to re-write the program, not with work for 3 customers in process and being in the middle of build season. I apologize if I was not clear. I was offering to take your source and re-compile to create a Linux executable. No disrespect intended but I don't need the formulas ;o). I'm an EE and have been designing opto-mechatronic embedded control systems for 30 years - I know the formulas.
Thanks anyways.
No disrespect intended but I don't need the formulas ;o)
Of course. I thought you were after some of the more arcane calculations, like solving for operating range given operating volts and desired minimum efficiency*. I've never seen that published anywhere.
Anyway, unless you have an old copy of Kylix the source wouldn't serve the purpose intended.
Oh well, the equations are out there for anyone who might be interested.
*it's not as useful as other calculations, I know, but I included it because it's interesting to play around with and may provide some insight
wireties
30-01-2012, 15:38
Anyway, unless you have an old copy of Kylix the source wouldn't serve the purpose intended.
Well, it just so happens that I do ... BTW, FIRST Team 1296 very much appreciates all the great advice you regularly disperse on CD!
There have been a number of occasions recently where I wanted to calculate a motor's applied voltage given rpm and amps. To make this more convenient I added another option to the motor calculator (http://www.chiefdelphi.com/media/papers/2432).
I have also changed the display to show waste heat watts instead of input watts, since that seems to be of somewhat more interest. Input watts is easily calculated by adding output watts and waste watts.
Thread created automatically to discuss a document in CD-Media.
Simple Motor Calculator (http://www.chiefdelphi.com/media/papers/2432?) by Ether
New version just uploaded. Includes VEX MiniCIM and BAG motors.
Thread created automatically to discuss a document in CD-Media.
Simple Motor Calculator (http://www.chiefdelphi.com/media/papers/2432?) by Ether
Motor Calculator has just been updated to include the now-legal Banebots M5-RS555-12 motor.
The new version (MCALC_2013b) (http://www.chiefdelphi.com/media/papers/download/3556) is at the bottom of the list of attachments.
Motor Calculator has just been updated to include all 2014 motors. Sorry for the delay. Better late than never :-)
http://www.chiefdelphi.com/media/papers/2432
Motor Calculator has just been updated to include am-2161 & am-2194 motors (for am-0914, 2193, & 0915 gearmotors)
http://www.chiefdelphi.com/media/papers/2432
wireties
03-02-2014, 20:10
Thanks again Ether!! You would not believe how much we use this utility.
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