Lathe tool changer turret - DC motor based

/************************************************************************************************************************************* LinuxCNC HAL component to implement ATC toolchanging on Hercus PC200 Lathe Based on "EMC2 HAL component to implement ATC toolchanging in Denford ORAC CNC lathes" (c) ArcEye 01122011 schooner30@tiscali.co.uk Modified by pippin88 - 07/10/2017 All values are metric Version 0c - The PC200 toolchanger has an 8 position unidirectional turret. There is an index sensor (PC200changer.index), and a position sensor (PC200changer.pocket) that pulses once per tool position. When the motor moves forwards, the turret rotates forward. The position sensor does not line up exactly with the actual tool position, but is past the tool position a bit - the turret reverses until the spring-loaded pins line up and jump into the locking holes. When the locking pins are fully deployed, they close a circuit (PC200changer.lock) The turret uses a simple DC motor. This is driven by an H-bridge (L298N) which takes two input signals to determine direction. motor A and motor B. A HIGH, B HIGH = motor off; A HIGH, B LOW = motor forward; A LOW, B HIGH = motor reverse; A LOW, B LOW = motor off; I use A HIGH, B HIGH for off, as this is less susceptible to noise than a resting LOW state. Compile the component with 'sudo comp --install PC200changer.comp' Below .hal file extracts give a specimen .hal connection guide. Place them as appropriate in .hal file ############################################################### # loading the toolchange component in .hal file ############################################################### loadrt PC200changer addf PC200changer servo-thread net tool-change iocontrol.0.tool-change => PC200changer.toolchange net tool-changed iocontrol.0.tool-changed <= PC200changer.toolchanged net tool-number iocontrol.0.tool-prep-number => PC200changer.reqtoolnumber net tool-oldnumber iocontrol.0.tool-number => PC200changer.currenttoolnumber net tool-prepare-loopback iocontrol.0.tool-prepare => iocontrol.0.tool-prepared net turret-lock PC200changer.lock <= hm2_7i43.0.7i76.0.0.input-25 #Turret Lock sensor (White) net turret-index PC200changer.index <= hm2_7i43.0.7i76.0.0.input-26 #Turret Index (Green) net turret-pocket PC200changer.pocket <= hm2_7i43.0.7i76.0.0.input-27 #Turret Pulse (Blue) ## GPIO33 = Turret motorA setp hm2_7i43.0.gpio.033.is_output true setp hm2_7i43.0.gpio.033.out true ### pull high at startup!!! Can change if needed ## GPIO34 = Turret motorB setp hm2_7i43.0.gpio.034.is_output true setp hm2_7i43.0.gpio.034.out true ### pull high at startup!!! Can change if needed net turret-motorA PC200changer.motorA => hm2_7i43.0.gpio.033.out net turret-motorB PC200changer.motorB => hm2_7i43.0.gpio.034.out net xhomed joint.0.homed => PC200changer.ishomedX net zhomed joint.1.homed => PC200changer.ishomedZ #setp PC200changer.times 125 ### where nnn is the new value - sets a sleep timer ################################################################################ ***************************************************************************************************************************************/ component PC200changer "This component controls the PC200 Lathe Auto Tool Changer. M6 calls this"; pin in bit toolchange "Receives signal from M6 that tool change required"; pin in s32 reqtoolnumber "Requested Tool Number - Tx data from M6. Only 1-8 allowed"; pin in s32 currenttoolnumber "Receives old tool number from hal / axis"; pin out bit toolchanged = false "Sends signal when tool change finished"; pin in bit index = 1 "State of turret index sensor"; pin in bit pocket = 1 "State of turret pocket sensor"; pin in bit lock = 1 "State of turret lock sensor"; pin out bit motorA = 1 "Motor signal A"; pin out bit motorB = 1 "Motor signal B"; pin in bit ishomedX = false "Status of X axis homing"; pin in bit ishomedZ = false "Status of Z axis homing"; pin out s32 turretposition = 0 "Turret Position - Initialised as a pin for debugging so we can check where it thinks it is"; pin out s32 turrethomed = 0 "Turret Homed signal - Initialised as a pin for debugging so we can check where it thinks it is"; param rw float times = 290 "Length of delay"; // Internal and debugging stuff pin out s32 progresslevel = 0; // tracks the progress of the toolchange, just here so it can be read easily //pin out s32 tnumber = 0; // Internal toolnumber to allow overrun of quadrant by 1 then reverse back onto it variable bool bWarn = false; // first toolnumber reminder variable float sleeptime = 0; // our own timer to set delay for locking - set to 0 for first run pin out bit indexState = 1; // current state of the index signal - for rising edge pin out bit lastindexState = 1; // previous state of the index signal - for rising edge pin out bit unlockState = 1; // current state of the index signal - for rising edge pin out bit lastunlockState = 1; // previous state of the index signal - for rising edge pin out bit pocketState = 1; // current state of the pocket signal - for rising edge pin out bit lastpocketState = 1; // previous state of the pocket signal - for rising edge pin out bit lockState = 1; // current state of the pocket signal - lock is detected on falling edge pin out bit lastlockState = 1; // previous state of the pocket signal pin out bit turretislocked = 0; option singleton yes; // makes no sense to have more than one of these components running - only one ATC function _; author "pippin88 pippin88@imagineant.com"; license "GPL"; ;; FUNCTION(_) { switch (progresslevel) { case 0: // idle waiting for toolchange request //first make sure X and Z axes are homed. If turret is not homed, home it if((toolchange==1)&&(turrethomed==0)&&(ishomedX)&&(ishomedZ)){ progresslevel = 1; //call case 1 - homing sequence break; } if((toolchange==1)&&(toolchanged==0)&&(turrethomed==1)) { // if tool change requested and not done and turret already homed if(currenttoolnumber && reqtoolnumber != currenttoolnumber && reqtoolnumber > 0 && reqtoolnumber < 9) { // if a valid number // switch off motor if already on - both pins high = stop motorA = 1; // "Motor input A"; motorB = 1; // "Motor input B"; //sleeptime = 0; progresslevel = 2; //call case 2 break; } else // if tool requested is out of range set the toolchanged flag via case 5 and exit // should only get this if tool table has more tools than ATC can have // otherwise emc will error the M6 command { progresslevel = 5; // switch off motor if already on - both pins high = stop motorA = 1; // "Motor input A"; motorB = 1; // "Motor input B"; } } if(!toolchange) { //Turn motor OFF motorA = 1; // "Motor input A"; motorB = 1; // "Motor input B"; toolchanged = 0; // reset toolchange flag after reset by linuxcnc } //if(toolchange && currenttoolnumber==0) // if no tool is set in axis - set axis to tool requested so that can work next time // { // switch off motor if already on // motorA = 1; // "Motor input A"; // motorB = 1; // "Motor input B"; // progresslevel = 5; // } break; case 1: // HOMING SEQUENCE // Turn motor forward motorA = 0; // "Motor input A"; motorB = 1; // "Motor input B"; // use a state machine to detect the index pulse only once indexState = index; // read the index sensor input pin if (lastindexState != indexState) { // compare the indexState to its previous state if (index == 0) { // if the current state is LOW then the index went from ON to OFF - FALLING EDGE turretposition = 8; //Set Tool Pocket 1 turrethomed = 1; //Set turrent homed flag if (reqtoolnumber == 8){ progresslevel = 4; //move to locking sequence } else { progresslevel = 2; //move to motor forward sequence } } } lastindexState = indexState; //store indexState for comparison next time around break; // index not triggered - get out of case 1 and go round again case 2: // UNLOCKING - use first pocket pulse to show that turret unlocked, and to prevent that first pulse counting as a position increment // Run forward - need to clarify pins etc motorA = 0; // "Motor input A"; motorB = 1; // "Motor input B"; //use a state machine to detect pocket sensor unlockState = pocket; // read the pocket sensor input pin if (lastunlockState != unlockState) { // compare the pocketState to its previous state if (pocket == 1) { // if the current state is HIGH then the button went from OFF to ON - RISING EDGE progresslevel = 3; } } lastunlockState = unlockState; // save the current state as the last state, for next time through the loop break; //get out of case 2 - - go round again case 3: // FORWARD TOOL FIND SEQUENCE - Forward move until desired tool position motorA = 0; // "Motor input A"; motorB = 1; // "Motor input B"; if(turretposition==0) { // if returning 0 something is wrong - should be homed and at pocket 1 at least rtapi_print_msg(RTAPI_MSG_ERR, "Error - counter error"); progresslevel = 12; // doesn't exist so will go to default, output msg and then sit in level 10 break; } //use a state machine to detect pocket sensor once per position only pocketState = pocket; // read the pocket sensor input pin if (lastpocketState != pocketState) { // compare the pocketState to its previous state if (pocket == 0) { // if the state has changed, increment the counter // if the current state is LOW then the button went from ON to OFF - FALLING EDGE turretposition++; //increment tool position counter if(turretposition > 8) turretposition = turretposition - 8; //we have gone round from 8 to 1 } } lastpocketState = pocketState; // save the current state as the last state, for next time through the loop if (turretposition == reqtoolnumber) { progresslevel = 4; //move to case 4 } break; //get out of case 3 - go round again case 4: // LOCKING SEQUENCE // Reverse locking move motorA = 1; // "Motor input A"; motorB = 0; // "Motor input B"; //use a state machine to detect lock sensor once only - detect falling edge lockState = lock; // read the pocket sensor input pin if (lastlockState != lockState) { // compare the pocketState to its previous state if (lock == 0) { // if the state has changed, increment the counter // if the current state is LOW then the lock circuit has grounded //Turn motor OFF motorA = 1; // "Motor input A"; motorB = 1; // "Motor input B"; turretislocked = 1; progresslevel = 5; } } lastlockState = lockState; // save the current state as the last state, for next time through the loop break; //get out of case 4 - go round again case 5: // clean up ready for next toolchange //sleeptime = 0; progresslevel = 6; toolchanged = 1; // signal finished break; //get out of case 5 - go round again case 6: //if(sleeptime < 1) //{ // sleeptime++; // break; //} progresslevel = 0; break; case 10: break; // should never get here but if we do then loop endlessly doing nothing default: progresslevel = 10; rtapi_print_msg(RTAPI_MSG_ERR, "Error state in PC200changer - now disabled - unload PC200changer"); break; } }