Transcript Futaba S3010 Standard Size Ball Bearing High Torque Servo

Steering Servo
How to control the car heading via a steering servo
Team: //noComment
Leader : Christian
Software Specialist : Matt
Hardware Specialist : Vic
Assistant : Andrew
Overview
 Hardware
 Futaba S3010 Specs
 Components Needed
 Wiring
 Interfacing
 Registers Used
 Register Diagram
 Analog to Digital Conversion
 PWM Review
 Mechanical Binding Test
 Software Implementation
 Summary
 References
 Questions
Hardware
Futaba S3010 Servo (1)
Futaba S3010 Specs
Control System: +Pulse Width Control
Required Pulse: 3-5 Volt P-P Square wave
Operating Voltage: 4.8-6.0 Volts
Operating Speed (4.8V): 200 ms/60 degrees at no load
Operating Speed (6.0V): 160 ms/60 degrees at no load
Pulse Span: 1000-2000usec
Dimensions: 1.6” x 0.8” x 1.5”
Weight: 1.40z (41g)
Components Needed
 32 bit ColdFire MCU FireBird32
 Smart Car chassis with mounted Futaba servo
 Bench Top Power Supply(5v)
 Jumpers
 Oscilloscope
 Potentiometer
Wiring
Powering the Servo
 Connect 5V from power supply to the RED pin on the servo
connector
 Tie the grounds of the ColdFire and the bench top supply
together
 Connect the BLACK ground pin from the servo to the Coldfire
ground
Connecting to Coldfire
 Connect WHITE control pin from servo to Coldfire PWM output
port (PF4)
Interfacing
MCU(Coldfire)
Power
Supply (5V)
Servo
Registers Used
TPM2SC – Status Control Register
TPM2MOD – Modulo Register (sets period)
TPM2C0SC – Channel Status and Control Register
TPM2C0V – Value Register (sets pulse width)
Register Diagram
Register Diagram
Analog to Digital Conversion
Initialization
 Select ADC clock source and divide by # bits for conversion
(ADCCFG)
Per Conversion
 Select channel to convert (ADCSC1)
 Wait for conversion complete (COCO)
 Read data from result registers (ADCRx)
Analog to Digital Conversion
//derived from Prof Sumey
int adcGet() //adc conversion on PTB4, 10 bit thus 0-1024 result, result then returned
{
//channel 0=PTB0... channel 7=PTB7
//channel 8=PTD0... channel 11=PTD4
// perform conversion
ADCSC1 = 4;// start conversion on PTB4 , channel 4
while (!ADCSC1_COCO){} // wait for conversion complete*
return ADCR; // grab 2-byte result and return it
}
void adcInit()
{
// ADC initialization:
ADCCFG = (0b10 << ADCCFG_ADIV_BITNUM) // select Busclk/4 (3MHz)
+ (0b10 << ADCCFG_MODE_BITNUM); // 10-bit mode
}
PWM Review
MCF51JM128 ColdFire® Integrated Microcontroller Reference Manual
Mechanical Binding Test
FOREVER
{
adcresult = adcGet();
dir(1000+adcresult);
}
//Max=1777us
//Min=1134us
NO
YES
Software
 void initializeMCU() {
…..
//SOPT2_CLKOUT_EN = 1;
…..
}
 PWM initialize()
TPM2SC = TPM2SC_CLKSA_MASK // select bus clock for timer clock
+ 8;
// divby-8 prescaler (8MHz / 8 = 1MHz Timer clock)
TPM2MOD = 10000; //Period = 20,000us= """20ms"""= f=50Hz
TPM2C0SC=0x38; //Set status control register
TPM2C0V = 1500; //Pulse Width = """1.5ms""“
*TPM2C0V*
Summary
How to control the car heading via a steering servo
References
 (1) “S3010 Std. HT Ball Bearing." S3010 Std. HT Ball
Bearing. N.p., n.d. Web. 17 Feb. 2015
 (2) “How Do Servos Work?" How Do Servos Work? N.p., n.d.
Web. 17 Feb. 2015.
 (3) "Futaba S3010 - Standard High-Torque BB Servo."
Futaba S3010 Servo Specifications and Reviews. N.p., n.d.
Web. 17 Feb. 2015
Questions?