Chapter 12

ENHANCEMENTS TO APT4


This chapter describes enhancements made to the APT4 system in versions SSR2, SSV2, SSR3 and SSV3.

12.1 Additional Conditional Transfer

Without changing the existing Conditional Transfer the following enhancements have been made:

12.1.1 The Logical IF Statement

General form: IF (logical expression) APT_statement where S is any executable APT statement except a DO statement or another IF statement. The logical IF statement is used to evaluate the logical expression and to execute or skip statement S depending on whether the value of the expression is true or false, respectively. A logical expression consists of: a) a single logical variable. Logical variables are defined and remain logical when the value .true. or .false. is assigned to. Assignment: LV =.TRUE. or LV = .FALSE. IF - example: IF (LV) APT-statement b) two arithmetic expressions combined with a relational operator Relational Operator Definition .GT. greater than (>) .GE. greater than or equal to (>) .LT. less than (<) .LE. less than or equal to (<) .EQ. equal to (=) .NE. not equal to (=/) Relational operators may be used to compare two arithmetic expressions. The comparison can be either true or false. Examples: Assume that the variables A, B and C are of real type. IF ((A-1.).GT.(2*B)) APT-Statement IF (A.EQ.B) APT-Statement IF(1.55.LT.(C**2.)) APT-Statement IF(C.EQ.2.75.E-2) APT-Statement c) one or more logical expressions (logical variables, or expressions containing relational operators; in the following represented by A and B) combined with a logical operator. Value of Logical Operator Use A B Expression .NOT. .NOT.A TRUE - FALSE FALSE - TRUE .AND. A.AND.B TRUE TRUE TRUE TRUE FALSE FALSE FALSE TRUE FALSE FALSE FALSE FALSE .OR. A.OR.B TRUE TRUE TRUE TRUE FALSE TRUE FALSE TRUE TRUE FALSE FALSE FALSE The only valid sequences of two logical operators are .AND..NOT. and .OR..NOT. ; Examples: Assume that the variables A, B and C are of real type and U, V and W of logical type. IF((A-1.).GT.B .OR.U.AND.V) APT-Statement IF(U.OR.V.OR..NOT.W) APT-Statement IF(C.GT.10.AND.B.EQ.(A-10)) APT-Statement Order of Computations in Logical Expressions. Operation Hierarchy Exponentiation (**) 1st (highest) Multiplication and division (* and/) 2nd Addition and subtraction (+ and-) 3rd Relationals (.GT.,.GE.,.LT.,.EQ.,.NE.) 4th .NOT. 5th .AND. 6th .OR. 7th For example, the expression: A.GT.D**B.AND..NOT.L.OR.N is effectively evaluated in the following order: 1) D**B Call the result W (exponentiation) 2) A.GT.W Call the result X (relational operator) 3) .NOT.L Call the result Y (highest logical operator) 4) X.AND.Y Call the result Z (2nd highest logical operator) 5) Z.OR.N Final operation

12.1.2 Use of logical IF in APT programs.

In the example of looping in chapter 6.4 of Volume 1 the radius R2 = 6.5 replaces radius R1 = 5 if A1 is equal to 10, 30 or 50. (01) R1 = 5 (02) R2 = 6.5 (03) A1 = 0 (04) ID1) RR = R1 (05) IF(A1.EQ.10.OR.A1.EQ.30.OR.A1.EQ.50) RR = R2 (06) X1 = RR*COSF(A1) (07) Y1 = RR*SINF(A1) (08) GOTO/X1,Y1,0 (09) A1 = A1+10 (10) IF(A1.LT.60)JUMPTO/ID1 (11) GOTO/P2 An equivalent manner of writing of the statements (04), (05) and (10) is: (04) ID1) RR = R2 (05) IF(A1.NE.10.AND.A1.NE.30.AND.A1.NE.50) RR =R1 (10) IF(60.GT.A1)JUMPTO/ID1

12.1.3 The computed JUMPTO statement (new format)

General form: JUMPTO/lb1,lb2,lb3,,,,,lbn,jmp Where: lbi are labels of executable statements in the program containing the computed JUMPTO statement. jmp is an integer variable which must be given a value before the JUMPTO statement is executed. This statement causes control to be transferred in the statement signed (LB1), LB2), LB3,....., or LBN), depending on whether the current value of JMP is 1, 2, 3, ........, or N, respectively. If the value of JMP is outside the range 1 < JMP < N, the next statement is executed Restriction: The maximum of labels in a statement is 46, the minimum 2. Example: JUMPTO/LB,15,ID2,15,VBL L11) A =7.5 ..... ..... 15) A = B**2+A ..... ..... LB) B= A-10 ..... ..... ID2) B = 10.3D-01 Explanation: In this example statement LB) will be executed next, if the value of the integer variable VBL is 1. If VBL is equal to 2 or 4 statement 15) is executed next, etc. If VBL is less than 1 or greater than 4, statement L11) is executed next.

12.2 Additional Part Program Structuring

12.2.1 The DO Statement (new format)

General form: DO / lb1, index = v1,v2,v3 Where: lbl is the label of an executable statement appearing after the DO statement in the program containing the DO. It defines the end of the DO LOOP. index is an integer variable called the DO variable. v1 Initial value assigned to INDEX at the start of the DO LOOP. v2 Test value. If INDEX exceeds the test value the DO LOOP is finished. v3 Increment to increase or decrease INDEX at each passage of the loop. V3 is optional. If it is omitted (together with the preceding comma) its value is assumed to be 1. v1, v2 and v3 are integer constants or integer variables, the values of which sould not exceed 2**31-1 or -2**31. The example of looping in chapter 6.4 can now be written in the following way: R1 = 5 R1 = 5 DO/ID1,A1=0,60,10 DO/ID1,A1=0,60,10 X1 = R1*COSF(A1) X1 = R1*COSF(A1) Y1 = R1*SINF(A1) Y1 = R1*SINF(A1) ID1) GOTO/X1,Y1,0 GOTO/X1,Y1,0 ID1) CONTIN

12.2.2 The CONTIN-Statement (new format)

CONTIN -> dummy statement CONTIN (abbreviation of continue) is a statement that may be placed anywhere in the part program without affecting the sequence of execution. It may be used to avoid ending the DO loop with a JUMPTO, arithmetic IF, another DO statement or a logical IF statement.

12.2.3 Considerations and Restrictions in using a DO Loop

o The indexing parameters of a DO statement (index,v1, v2, v3) should not be changed by a statement within the range of the DO loop. o There may be other DO statements within the range of a DO statement. All statements in the range of an inner DO must be in the range of each outer DO. A set of DO statements satisfying this rule is called a nest of DO's. It is possible to nest maximally 10 DO loops. DO/LB1,I=1,5,2 *------ -----* DO/LB1,I=1,5,2 .............. ............... DO/LB1,J=1,10 +------ -----+ DO/LB2,J=1,10 ............. ............... ............. -----+ LB2)X=X+1 ............. ............... LB1)CONTIN *+----- -----* LB1)CONTIN * range of outer DO + range of inner DO o A transfer out of the range of any DO loop is permissible. o The extended range of a DO is defined as those statements that are executed between the transfer out of the innermost DO of a set of completely nested DO's and the transfer back into the range of this innermost DO. DO/LB1,I=1,5,2 .............. DO/LB1,J=1,10 IF(I.EQ.J)JUMPTO/OUT -----> OUT)............ .............. .............. IN) ............. <----- JUMPTO/IN ............. LB1) CONTIN o Transfer into the range of a DO is permitted only if such a transfer is from the extended range of a DO. The indexing parameters (index,v1,v2,v3) cannot be changed in the extended range of a DO. o A statement that is the end of the range of more than one DO statement is within the innermost DO. o The last statement in the range of a DO loop must be an executable statement or CONTIN. It cannot be a JUMPTO statement of any form, an arithmetic IF statement, another DO statement or a logical IF statement.

12.3 Additional Arithmetic and Vector Expressions

12.3.1 Extended Number Definition

A FORTRAN-like definition of real numbers using E and D exponents is included. Example: P1 = POINT/ .3D1,6.0E-01,-25.D-2

12.3.2 Vector Expressions

With two new operators for the vector dot product (.) and the vector cross product (*) vector and points can be used in arithmetic expressions or in new available vector expressions. Examples: R1 = V1 (.) V2 V3 = V1 (*) V2 V4 = R2 * V3 with Ri as real variables or constants and Vi as vector variables

12.4 Additional CANON/ Statement

ON CANON/ OFF CANON/ON causes the suppression of the TRANSLAT warning diagnostic 50 "GEOMETRIC VARIABLE BEING USED HAS BEEN PREVIOUSLY DEFINED WITH THE SAME MODE. FIRST DEFINITION DEFINITION OVERRIDDEN". CANON/OFF cancels command CANON/ON and resores the initial setting.

12.5 Additional EXFILE output manipulation

The extended output (EXFILE) manipulation consists of o Output specification for various ARELEM output o Specification of EXFILE segments o Extraction of segment point count o Extraction of segment data for reuse in the same part program o Use of EXFILE segment data in the isoparametric milling with GOLOFT. The old CLDAT statement to switch APT3 or APT4 CLTAPE output ON or OFF. 3 ON CLDAT/ x, 1, { , { 4 OFF and to read previously created APT4 CLTAPE information 11 CLDAT/{ , 2,4 ›, rec1, rec2! 12 remain unchanged.

12.5.1 EXFILE output CLDAT definitions

CLDAT allows to specify which data is to be included in EXFILE for each cutter location. The available data types are: TP x, y, z of tool point TA i, j, k of tool axis TV i, j, k of tool travelling vector PDS x, y, z of drive surface point NDS i, j, k of drive surface normal PPS x, y, z of part surface point NPS i, j, k of part surface normal UVPDS u, v, p drive surface parametric values UVPPS u, v, p part surface parametric values The TP and TA datatypes are identical with the existing CLDATA output (TA in MULTAX/ON case). These two types are the only ones which are written onto APT-CLTAPEs. TV, PDS, NDS, PPS and NPS can be used together with motion commands which produce these informations. UVPDS and PVPPS only have a meaning if the surfaces involved are parametric. The format of the output control CLDAT statement is the following: CLDAT/ datatypes All nine datatypes defined above are allowed in deliberate order. CLDAT/NORMAL switches back to the normal tool point and tool axis (MULTAX) output. Nested datatype definitions are not allowed, i.e. a new definition can only be given after CLDAT/NOMORE has been issued. The additional output specification cannot be transformed to the APT3-CLDATA format for postprocessing. Therefore the APT3 output has to be switched coding the following statement: CLDAT/ 0,1,3, OFF Using the APT4 CLTAPE standard for postprocessing these additional data can be used.

12.5.2 EXFILE output segments

For retrieving EXFILE data from one or more cut sequences at any later place in the part program the following segment definition statement can be used: START, id ›,datatypes! CLDAT/ NOMORE, id The resulting data from motion components between a CLDAT/START,.... and a CLDAT/NOMORE statement can be retrieved later by using the identifier 'id' (see sections 12.5.3, 12.5.4). 'id' can be any number, real variable or real expression. Nested segment definitions are not allowed. Datatypes can be defined optionally if they have not been defined before. The CLDAT/START,... statement enhances the existing data extraction feature which only allows to extract TP and TA from the most recent cut sequence.

12.5.3 Additional CLDATA location count extraction

The format for determining the number of cutter location generated by all motion statements within the identified CLDAT section is: Variable name =NUMF(CLDATA,id) where id is the identifier for one of the CLDAT sections previously defined. The statement may appear anywhere after the CLDAT/NOMORE,id statement of the referenced section. See example in chapter 12.5.5. The NUMF (CLDATA) function to retrieve the location count of the most recent cutter path is still available.

12.5.4 Additional Part Program Definitions with EXFILE Data

According to the datatypes described in 12.5.1 all EXFILE data can be used for geometric and scalar assignments.

12.5.4.1 Additional Point Definitions

The format for defining a point with coordinates identical to a specified cutter location or to a specified point on the drive or part surface and generated within an indentical CLDAT section is: TP Variable name = POINT/CLDATA, id, PDS, n PPS where: id integer identifier of the CLDAT section TP point identical to cutter location PDS point identical to point on drive surface PPS point identical to point on part surface n cutter location sequence number

12.5.4.2 Additional Vector Definitions

The format for defining a vector with components identical to a specified tool axis orientation, or motion vector or identical to a specified normal of the drive or part surface and generated within an identified CLDAT section is: TA Variable name = VECTOR/CLDATA, id, TV, n NDS NPS where: id integer identifier of the CLDAT section TA vector identical to tool orientation vector TV vector identical to tool motion vector NDS vector identical to normal of drive surface NPS vector identical to normal of part surface n cutter location sequence number

12.5.4.3 Additional Scalar Definitions

The format for defining a scalar identical to a specified u - parameter, v - parameter or patch number of a drive or a part surface within a identified CLDAT section is: UDS Variable name = CLDAT(id, VDS, n) PDS UPS VPS PPS where: id integer identifier of the CLDAT section UDS scalar identical to u-value of drive surface VDS scalar identical to v-value of drive surface PDS scalar identical to patch nr. of drive surface UPS scalar identical to u-value of part surface VPS scalar identical to v-value of part surface PPS scalar identical to patch nr. of part surface n cutter locations sequence number

12.5.5 Programming Example

PARTNO CLDAT TEST ...... (22) CLDAT/0,1,3,off (23) CLDAT/START,100,PPS,TP,PDS $$ ONLY POINTS DEFINED (24) TLRGT,GORGT/PLY,PLX $$ BLOCK 1 (25) N25=NUMF(CLDATA) (26) GORGT/PLY,ON,PLZ (27) N27=NUMF(CLDATA) (28) TLON,GORGT/PLZ,ON,PLXX (29) N29=NUMF(CLDATA) (30) CLDAT/NOMORE,100 (31) CLDAT/0,1,3,OFF ...... (44) CLDAT/START,200,NDS,TV,NPS,TA $$ ONLY VECTORS DEFINED (45) GOLFT/LBON,TO,JPL $$ BLOCK 2 (46) GOLFT/JPL,RBON (47) GORGT/RBON,PLN (48) GORGT/PLN,LBON (49) CLDAT/NOMORE,200 ...... (66) CLDAT/START,300,UVPPS,UVDPS $$ ONLY SCALARS DEFINED (67) GO/C,S,Z $$ BLOCK 3 (68) GOUP/C,PAST,Z1 (69) CLDAT/NOMORE,300 (70) GOTO/SETPT ...... (105) N100=NUMF(CLDATA,100) $$ DATA RETRIEVING (106) N200=NUMF(CLDATA,200) (107) N300=NUMF(CLDATA,300) (108) P1 = POINT/CLDATA,100,TP,1 (109) P2 = POINT/CLDATA,100,PDS,N100/2 (110) P3 = POINT/CLDATA,100,PPS,n100 (111) V1 =VECTOR/CLDATA,200,TA,1 (112) V2 =VECTOR/CLDATA,200,TA,N200 (113) V3 =VECTOR/CLDATA,200,NDS,2 (114) V4 =VECTOR/CLDATA,200,NPS,N200-1 (115) S1 = CLDATF(300,UDS,1) (116) S2 = CLDATF(300,UPS,2) (117) S3 = CLDATF(300,VDS,3) (118) S4 = CLDATF(300,VPS,N300-2) (119) S5 = CLDATF(300,PDS,N300-1) (120) 36 = CLDATF(300,PPS,N300) ...... FINI

12.6 Additional TLAXIS features

To provide compatability with APT3 and to allow new features, the TLAXIS statement has been enhanced as follows:

12.6.1 Existing /36OAPT and APT-AC language (APT3)

a,b,c TLAXIS/ vector NORMPS TLAXIS/ NORMDS TLAXIS/ 1 1 TLAXIS/ PARLEL, 2 1 vector TLAXIS/ ATANGL, ,alpha, 2 CUTANG,beta

12.6.2 Existing APT4 Language

TLAXIS/ a,b,c NORMPS TLAXIS/ NORMDS 1 TLAXIS/ PARLEL, ›,ra,hi! 2 x,y,z TLAXIS/ a,b,ra,hi,gamma, ,delta i,j,k

12.6.3 New TLAXIS Language

All APT3 and APT4 formats are allowed together with the following additions.

12.6.3.1 Additional Switch to 3-axis Mode

To maintain the last calculated cutter axis for all following motions (3-axis) TLAXIS/LAST can be coded. This statement has the same meaning as TLAXIS/1.

12.6.3.2 Additional Ruled Surface TLAXIS Definition

To define the ruled surface TLAXIS the following can be coded: PS ›,ra,hi! TLAXIS/PARLEL, DS ›,RADIUS,ra! ›,HIGHT,hi! o PS and DS means part or drive surface control o The radius and height information are optional and define a disk cutter if a CUTTER statement has been issued before. If only a RADIUS,ra or HIGHT,hi information is given, the parameter which is not given is calculated from the given CUTTER statement.

12.6.3.3 Additional full TLAXIS Statement

The full 4- and 5-axis TLAXIS statement can be coded as follows: PS TLAXIS/ATANGL, ,alpha›,RADIUS,ra!›,HIGHT,hi! $ DS › PERPTO,vector º º plane º PARLEL, º line º, º MOTDIR º º › LAG › beta º CUTANG º, º, › › LEAD › AUTO o ATANGL introduces the angle which the tool axis has to maintain with the PS or DS geometry. Note that the angle alpha is equal (180 - gamma) of the APT4-TLAXIS statement (see 12.6.2). o PS and DS means part and drive surface control. o The radius and height information is optional and has the same meaning as under 12.6.3.2. o PERPTO,vector , PARLEL,line or PARLEL,plane signal a 4-axis case where the tool axis has to maintain a 90 degree relation to a vector (explicitly given vector or the plane-and line-nornal). o MOTDIR means that the cutter axis has to be perpendicular to the present motion direction. o The CUTANG specifies the tool axis has to be perpendicular to the motion direction. If LEAD and LAG are omitted, the sign of beta is responsible for the leaning direction of the tool axis: Negative: The tool axis leans to the motion direction; Positive: The tool axis leans back from the motion direction or, in other words, the tool axis maintains an angle of (90+beta) degrees with the motion direction. LEAD and LAG can be coded to express the same tool axis constraint in respect to a positive anlge beta. AUTO is added for some not yet existing collision-related tool axis control.

12.7 Additional Print control

To structure the part program listing without the side effect of the APT4 - PRINT/0 statement, two actions are made. The PRINT/0 statement controls only the listing in the XECUTION phase while the TRANSLAT listing is controlled by a new EJECT statement as follows: EJECT