Transcript Motor Drive

By: Team Short Circuit;
Leader: Miranda Gumbert
Hardware Specialist: George Tittnich
Software Specialist: Jordan Shawley
Assistant: Patrick Tunney
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Understanding the Problem
Hardware
Components Needed
 Pololu 1212
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 MC33926
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Wiring
Registers Used
Software Implementation
Summary
References
Q&A
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Drive and Control the Motor
Being able to make it go from stopped to full
speed
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32 bit ColdFire MCU FireBird32
Smart Car chassis with mounted brushed
motor
Pololu 1212
***Make sure to raise your car using your parts
box***
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Operating Voltage: 5V-28V
Operating Current: 3A-5A
Overheating Issues:


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Thermal Tape
Heat Sink
MC33926 – Throttle Control H-Bridge
Power
Supply
MCU
PTE3
Motor
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TPM1CnSC
TPM1CnV
TPM1C1SC_ELSnx
Initialize motorDC as global variable
 Set up ADC for PWM
 Divide Result for values 0-100
 Use the potentiometer to adjust speed
 Convert values to ticks and update
Channel 1
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START
Initialize
motorDC=0
ADC conversion
Save result to
motorDC
motorDC/10=
value 0-100
Update TPM1C1V
motorISR()
Interrupt VectorNumber_Vtpm1ch1 void MotorISR(void)
{
int mSeconds = 1000;
PTED_PTED6 = 1;
//SPSclk
TPM1C1SC & = 0x7F;
//AND to extract bit
if(motorB)
//PTED_PTED3
//convert to microseconds
mSeconds = motorDC*10;
//1ms= 1000 microseconds
else
mSeconds = (100 – motorDC)*10;
}
TPM1C1V += 3 * mSeconds;
//update
PTED_PTED6 = 0;
//update
}
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Setting constraints
Addressing 2 special cases:
1.
2.
0%
100%
Figure 1: Duty Cycle at 26%
Figure 2: Duty Cycle at 76%
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Use the Pololu 1212 to run the mounted
brushed motor using PWM control
Use the potentiometer to change the duty cycle
Be sure to prop up the car prior to operation
Be sure to account for 0% and 100% duty cycle
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"MC33926 Motor Driver Carrier." MC33926
Motor Driver Carrier (n.d.): n. pag. Web. 24 Feb.
2015.
Semiconductor, Inc. Freescale. "5.0 A Throttle
Control H-Bridge." MC33926, 5.0 A Throttle
Control H-Bridge (n.d.): n. pag. 5.0 A Throttle
Control H-Bridge. Web. 24 Feb. 2015.
Sumey, Jeff. "Jeff Sumey's Virtual Resource
Center." Jeff Sumey's Virtual Resource Center. Jeff
Sumey, n.d. Web. 24 Feb. 2015.