Transformation parameters (P-AXIS-00370)


Transformation parameters of axis specific command value transformation


The transformation parameters are entered in this array corresponding to the selected transformation ID P-AXIS-00369.


trafo.actual_pos.param[i] with i = 0 … 74 (Maximum number of transformer parameters,

Data type


Data range

Meaning (depends on transformation ID)

ID 1:

param[0]     h (*)

param[1]     k0 (*)

param[2]     k1 (*)

param[3]     k2 (*)

param[4]     φNorm Normalization of motor angle (*)

(*see equations of the functions)


ID 2:

param[0]     Crank length l1

param[1]      Con-rod length l2

param[2]      Eccentricity e

param[3]      Solution range for motor angle ϕM

0:.0..180 degrees

                    1: 180..360 degree

param[4]      Moving direction of linear axis

                    0: positive

                    1: negative

param[10]    Zero point offset of linear axis


ID 4:

param[0]     la Distance 1 hinge points

param[1]     lb Distance 2 hinge points

param[2]     Crank length lh

param[3]     Offset zero position linear axis

param[4]     Rotation direction of axis B

                    0: positive

                    1: negative

Axis types




R: ----

Default value


Drive types




ID 1: e- function


trafo.command_pos.param[0] 10000

trafo.command_pos.param[1] 1.0

trafo.command_pos.param[2] 2.0

trafo.command_pos.param[3] 1.0

trafo.command_pos.param[4] 1800000

ID2: Crank


trafo.command_pos.param[0] 1000000

trafo.command_pos.param[1] 3000000

trafo.command_pos.param[2] 0

trafo.command_pos.param[3] 0



With eccentricity e != 0 and specific parameter settings (e.g. (l2-l1) < e), there may be limitations of angle movement range because of jammings in the kinematic structure! In this case the drive movement range of both solutions is smaller than 360 degrees (see following picture).

ID4: Crank with linkage by linear axis


trafo.command_pos.param[0] 1000000

trafo.command_pos.param[1] 1410000

trafo.command_pos.param[2] 1000000

trafo.command_pos.param[3] 0

trafo.command_pos.param[4] 0

If the kinematic is (β=0) in zero position, the transformation delivers for the drive position 0 for ls. If necessary, by param[3] an offset to this position can be defined. (Example: Drive position at β=0 is 50mm -> the offset value has to be set on 50mm). In mathematical sense, the default rotational direction of the B axis is positive. This can be adapted by the parameter trafo.command_pos.param[4], see the figure below.