1 SPIRIT S S ilicon ilicon P P rairie rairie I I nitiative on nitiative on R R obotics in obotics in I I nformation nformation T T echnology echnology DC Motor DC Motor Parameters Parameters
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SSilicon ilicon PPrairie rairie IInitiative on nitiative on RRobotics in obotics in IInformation nformation TTechnologyechnology
DC Motor DC Motor ParametersParameters
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Mark max Torque Y Axis
Mark Max RPM X Axis
X
X
Connect the points with a straight line
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X
X
Locate the Mid Point RPM
Trace a horizontal line to the Y Axis
This is the Design Torque Value
X
Mid Point RPM
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ALWAYS Record, Describe and Date the Data
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Measuring Armature Coil Resistance
The Multi-Meter selector is set to read resistance in units called ohms (). The selector is set to the lowest range (0-200 )
The Value measure is 0.9 ohms.
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Measuring Armature Coil ResistanceMeasuring Armature Coil Resistance
Set the meter to read ohms. Use the lowest range.
Short the meter leads and record the value. This is the meter error value.
Attach your meter to the two motor leads.
Slowly turn the armature shaft and record values at 45° intervals. Average these values.
Caution: Turning the armature shaft quickly, induces a current in the armature windings. This Will damage the meter.
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Calculate the Stall Current
I = ER
Ohm’s Law
The basic Algebra of electronics
E = VoltageI = Current in Amperes
R = Resistance in Ohms,
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Determining the Torque Value
ALWAYS Record, Describe and Date the Data
DF
F = Force (lbs.) 3 lbs
D = Length (ft.) .5 ft
Q = Torque (ft.lbs.)
Q = D x F
1.5 ft.lbs. = .5 ft. x 3 lbs.
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Evaluating DC Motors
Determining Robot Speed
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ALWAYS Record, Describe and Date the Data
Robot Speed EquationsUse this equation to predict the TekBot’s speed
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