Chapter 16 Feedback controlof motors, based on Demo2017.c and PIDRobotDemo. c CEG2400-Microcomputer Systems Reference: ww.tic ac uk/micromouse/PRESENTAT/ONS/Heretic. ppt http:/ww.cse.cuhk.edu.hk/khwong/ceg2400/pidrobotdemo093.c CEG2400 Ch16: feed back control v7f
Chapter 16 Feedback control of motors, based on Demo2017.c and PIDRobotDemo.c CEG2400 - Microcomputer Systems CEG2400 Ch16: feedback control V7f 1 Reference : www.tic.ac.uk/micromouse/PRESENTATIONS/Heretic.ppt http://www.cse.cuhk.edu.hk/khwong/ceg2400/PIDRobotDemo093.c
Objectives 1)(a)Study DC motors, (b Servo motors 2)Study stepping Motors 3 Study open-loop and closed-loop control 4)Control methods Proportional feedback control l)Pid proportional-integral-derivative) control CEG2400 Ch16: feed back control v7f
Objectives 1) (a)Study DC motors, (b) Servo motors 2) Study Stepping Motors 3) Study open-loop and closed-loop control 4) Control methods – I) Proportional feedback control – II) PID (proportional-integral-derivative) control CEG2400 Ch16: feedback control V7f 2
1a) Direct Current (DC motors For robots CEG2400 Ch16: feed back control v7f
1a) Direct Current (DC) motors For robots CEG2400 Ch16: feedback control V7f 3
Motors Our robot C motor with speed encoder CEG2400 Ch16: feed back control v7f
Motors • Our robot • DC motor with speed encoder CEG2400 Ch16: feedback control V7f 4
Small direct current d.c motors Speed(~1200-2000rpm) Operates on a 3 5 Volt, Can use gear box e.g. ratio 58: 1) 田宫四驱车配件15351PRO版专用双头马达, to increase torque picture from http://item.taobao.com/item.htm?id=1606576457&tra celog=newcardfavirate Use H-bridge circuit to boost up current from the ttl level to motor driving level CEG2400 Ch16: feed back control v7f
Small Direct Current D.C. motors • Speed (~ 1200-2000 rpm). • Operates on a 3~5Volt, Can use gear box (e.g. ratio 58:1) to increase torque • Use H-bridge circuit to boost up current from the TTL level to motor driving level. CEG2400 Ch16: feedback control V7f 5 田宫四驱车配件15351 PRO版专用双头马达 , picture from http://item.taobao.com/item.htm?id=1606576457&tra celog=newcardfavirate
Motor control chip L293D: H-bridge circuit, up 2A H-bridge Chips DIR left motor 2(1A) 1Y3 direction RDiR LEN 1(EN12) LDIR Left-motor right motor 7(2A (2Y6 direction 10(3A) REN 0(3￥11 Right-motor LEN: left motor RDIR 9EN34 enable REN: right 154A) (4Y)14 motor enable CEG2400 Ch16: feed back control v7f 6
Motor control chip • H-bridge Chips • L293D: H-bridge circuit, up 2A • LDIR: left motor direction; RDIR: right motor direction • LEN : left motor enable; REN : right motor enable CEG2400 Ch16: feedback control V7f 6 LEN LDIR REN RDIR 2 (1A) 1Y(3) 1(EN1/2) 7(2A) (2Y)6 10(3A) (3Y)11 9(EN3/4) 15(4A) (4Y)14 Left-motor Right-motor
Servo motors (based on dc motor) w Can achieve rotational angle control Application robotics, target pointing The motor shaft is attached to a rotational variable resistor (potentiometer) When the motor rotation has adjusted the variable resistor to the correct rotational angle, the electronic circuits circuit stops the motor Minimum Pulse Output spline Drve Gears puse Whdth1ms Servo Case Control Circut Neutral Postion Puse Width 1.5ms Maxmum Puse Motor pulsEwidth 2ms https://www.jameco.com/jameco/workshop/howitworks/how-servo-motors-work.html https:/electronicspost.com/describe-the-different-types-of-resistors/ Howdoservomotorsworkhttps:/www.youtube.com/watch?v=j8atdmeqzsc Common control method https:/ww.youtube.comwatch?v=hyugige4pgkeg2400Ch16:feedbackcontrolbyadjustingpulsewidth Vlf 12ms→01800
Servo motors (based on DC motor) • Can achieve rotational angle control • Application: robotics, target pointing • The motor shaft is attached to a rotational variable resistor (potentiometer) • When the motor rotation has adjusted the variable resistor to the correct rotational angle, the electronic circuits circuit stops the motor. CEG2400 Ch16: feedback control V7f 7 https://www.jameco.com/jameco/workshop/howitworks/how-servo-motors-work.html https://electronicspost.com/describe-the-different-types-of-resistors/ ** How do servo motors work: https://www.youtube.com/watch?v=J8atdmEqZsc https://www.youtube.com/watch?v=hYu9fGE4pCk Common control method by adjusting pulse width 1-2ms→ 0-180o
Use of servo motors aking humanoid robots or Robot arms https://www.youtube.com/watch?v=n1avnnzGra https://www.youtube.com/watch?v=nz6v63u-d8 CEG2400 Ch16: feedback control Vlf
Use of servo motors • Making humanoid robots , or • Robot Arms • https://www.youtube.com/watch?v=n_1aVNnz9rA • https://www.youtube.com/watch?v=NZ6V63u_-D8 CEG2400 Ch16: feedback control V7f 8
2 ) Stepping motor (stepper) Stepping motors are good positional control motors used widely in digital controlled machineries such as digital arm-clocks printers, disk drives etc The stepping motor in our robot How does a stepping motor work? https:/www.youtube.com/watch?v=twmai3oirnm https://www.youtube.com/watch?v=eyqwliowziu CEG2400 Ch16: feedback contro Vlf
CEG2400 Ch16: feedback control V7f 9 2) Stepping motor (stepper) • Stepping motors are good positional control motors used widely in digital controlled machineries such as digital arm-clocks, printers, disk drives etc. How does a stepping motor work? https://www.youtube.com/watch?v=TWMai3oirnM https://www.youtube.com/watch?v=eyqwLiowZiU The stepping motor in our robot
Stepping motor(4-phase)and circuit Digital outputs Crest driver Tp3oss(Y Tip+ )x4 P355 Large current stepping motors need current Protection P6( drivers 50几 Pb (5)15 IN3 Co 50 6VN/2V EPPING M。 ToR DRIVER 3.3V Smaller current Stepping motors can be driven by modern microcontrollers Tiva C Launch Pad directly by GPlO outputs 10 Motor R DIRiny drivers 平平平 CEG2400 Ch16: feedback control Vlf
Stepping motor (4-phase) and Circuit • Large current stepping motors need current drivers • Smaller current Stepping motors can be driven by modern microcontrollers directly by GPIO outputs CEG2400 Ch16: feedback control V7f 10 Digital outputs
