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1. FANUC 5 AXIS PROGRAMMING CODES 1.1. TOOL CENTER POINT (TCP) The G43.4/G43.5 codes enable the operator to carry out a tool length compensation not only during 3-axis machining but also during the execution of a 5-axis program. The correct syntax of the command is G43.4 Hn (TCP Type 1) Activation of the TCP by indicating the tool direction through the head corners. By Hn the operator-input corrector is meant in which the length of the tool mounted in the electrospindle is found and that needs to be measured (from spindle nose to tool end). G43.5 Hn Q… I… J… K… (TCP Type 2) Activation of the TCP by indicating the tool direction through the head corners. By Hn the operator-input corrector is meant in which the length of the tool mounted in the electrospindle is found and that needs to be measured (from spindle nose to tool end). With I J and K the tool direction vectors are defined. With Q the tool inclination angle is defined. G49 H0 It deactivates the compensation of the tool length in space. Hereafter described are the machine configuration parameters for using the TCP 19666 Pivot value 19680 Machine type, normally 2 19681 C AXIS 19682 C-axis rotation axis 19686 B AXIS 19687 Rotation direction 19697 B-axis rotation axis All parameters relating to the TCP function are those going from 19665 to 19745. For using the Fanuc portable keyboard with activated TCP the tool length value must be entered in parameter 12318. Example of configuration of the TCP table for the Ares machining centre. 19666 135000 19680 2 19681 5 19682 3 19686 4 19687 2 19697 3 After activating the G43.4 function and if set correctly, by moving the machining centre rotary axes an interpolation of the X, Y and Z axes will be noticed: practically the tool bit will stand still in space and the linear axis dimensions (XYZ) will remain the same, even changing the position of the rotary axes (B/A – C). 1.2. CREATION OF VIRTUAL WORK PLANES (TWP) The TWP function enables programming any machining function in a rotated space with angles defined at will with respect to the Cartesian triplet of the machine tool. This enables the operator to program the definition of the profile to define in the normal Cartesian system (XYZ), for then delegating the CNC the task of calculating the axis handling according to virtual planes deriving from rotation. For establishing the rotation direction of the virtual triplet refer to the right hand rule. Right hand rule. It is possible to define a virtual work plane in different ways : 1.2.1. G68.2 (standard twp) G68.2 Xx0 Yy0 Zz0 Iα Jβ Kγ It sets the new coordinate system (virtual plane) by using Eulero’s angles (see enclosed figure) where: Xx0 Yy0 Zz0 Origin of the new coordinate system Iα Jβ Kγ Eulero’s angle for determining the orientation of the new coordinate system CONVERSION OF COORDINATES THROUGH EULERO’S ANGLE Conversion from the workpiece XY-Z coordinate system to the X’-Y’Z coordinate system Conversion from the X’-Y’-Z coordinate system 1 to the X’-Y’’Z’’ coordinate system 2 Conversion from the X’-Y’’-Z’’ coordinate system 2 to the Xc-Yc-Zc characteristic coordinate system The conversion of the coordinates is carried out by rotating around the origin of the workpiece coordinate system. Coordinate system 1 is the coordinate system obtained by rotating the workpiece coordinate system by α degrees around the Z axis. Similarly, coordinate system 2 is the coordinate system obtained by rotating coordinate system 1 by ß degrees around the X axis. The coordinate system of the characteristic is the coordinate system obtained by translating by (Xo, Yo, Zo) from the workpiece coordinate system origin the coordinate system determined by the rotation of coordinate system 2 by γ degrees around the Z axis. FOR INSTANCE: Z tool axis, B and C rotary C: First rotary axis (master) axes (with intersecting axes) B: Second rotary axis (master) Tool holder compensation = Controlled Parameter N. 19666 point Tool length corrector = H01 Block N3: Tool center defines a characteristic coordinate system within the workpiece coordinate system. Block N4: brings the tool controlled point on Z30.0 point into the characteristic coordinate system. Block N5: automatically controls the rotary axes. Block N6: carries out the tool length compensation within the characteristic coordinate system. Brings the tool center on the characteristic coordinate system origin. The following figure illustrates the behaviour of the machining centre during the execution of the exemplifying program. Example of program 1 (with intersecting axes) Block N3 Controlled point Coordinate system of XcBlock N4 Coordinate system of X-YZ workpiece Block N5 Block N6 1.2.2. G68.3 (twp by tool axis direction) Yc-Zc characteristic Definition of a virtual work plane that is perpendicular to the tool direction. G68.3 Xx0 Yy0 Zz0 Rα where: Xx0 Yy0 Zz0 Origin of the new coordinate system Rα Rotation of the plane around Z for defining the direction of the newly-generated plane (by default 0°) 1.2.3. G68.2 P… (Guidance twp Option request) With series 30 – 31 new ways for defining the virtual plane have been implemented ; they are described below. 2.3.1.1. Rotation from original triplet G68.2 P1 Qq Xx0 Yy0 Zz0 Iα Jβ Kγ where: Xx0 Yy0 Zz0 Origin of the new coordinate system Iα Jβ Kγ Angles for determining the orientation of the new coordinate system (no Eulero); rotations with order defined in Q parameter Qq Order in which the axes are rotated (by default Q123) 2.3.2.1. Rotation through 3 points on the plane G68.2 P2 Q0 Xx0 Yy0 Zz0 Rα (Origin of the new coordinate system) G68.2 P2 Q1 Xx1 Yy1 Zz1 (coordinate P1) G68.2 P2 Q2 Xx2 Yy2 Zz2 (coordinate P2) G68.2 P2 Q3 Xx3 Yy3 Zz3 (coordinate P3) where: Xx0 Yy0 Zz0 Origin of the new coordinate system Xx1 Yy1 Zz1 Coordinates of first P1 point Xx2 Yy2 Zz2 Coordinates of second P2 point Xx3 Yy3 Zz3 Coordinates of third P3 point Rα Rotation of the plane around Z for defining the direction of the newly-generated plane (by default 0°) N.B. It is necessary to specify all the plane generating blocks in order to obtain the desired virtual plane 2.3.3.1. Rotation through 2 vectors G68.2 P3 Q1 Xx0 Yy0 Zz0 Iα1 Jß1 Kγ1 (1st vector) G68.2 P3 Q2 Iα2 Jß3 Kγ2 where: Xx0 Yy0 Zz0 Origin of the new coordinate system Q1 Iα1 Jβ1 Kγ1 Definition of the first vector Q2 Iα2 Jβ3 Kγ2 Definition of the second vector (2nd vector) 2.3.4.1. Rotation through the projection angles G68.2 P4 Qq Xx0 Yy0 Zz0 Iα Jβ Kγ where: Xx0 Yy0 Zz0 Origin of the new coordinate system Iα Jβ Kγ Definition of the projection angles for plane identification 1.2.4. G68.4 P… (incremental twp - Guidance twp Option request) Incremental definition of a virtual work plane. Its use requires the generation of a previous virtual work plane and it uses the same definition rules. Therefore the result will be: G68.4 P1 Qq Xx0 Yy0 Zz0 Iα Jβ Kγ (angles from original triplet) G68.4 P2 Q0 Xx0 Yy0 Zz0 Rα (Origin of the new coordinate system) G68.4 P2 Q1 Xx1 Yy1 Zz1 (coordinate P1) G68.4 P2 Q2 Xx2 Yy2 Zz2 (coordinate P2) G68.4 P2 Q3 Xx3 Yy3 Zz3 (coordinate P3) G68.4 P3 Q1 Xx0 Yy0 Zz0 Iα1 Jß1 Kγ1 (1st vector) G68.4 P3 Q2 Iα2 Jβ3 Kγ2 (2nd vector) G68.4 P4 Qq Xx0 Yy0 Zz0 Iα Jβ Kγ (projection angles) 1.2.5. TWP deactivation (G69) 69 command cancels any previously activated coordinate system. 1.2.6. Tool automatic orientation (G53.1 / G53.6) After activating the virtual work plane it is possible to orient the machining centre head perpendicularly with respect to the generated plane in 2 ways. G53.1 Automatic orientation of the rotary axes perpendicularly with respect to the new generated triplet without using the TCP. G53.6 Hh Automatic orientation of the rotary axes perpendicularly with respect to the new generated triplet by using the TCP.