KIN_TYP_36 – SCARA kinematics

Kinematic structure

The robot kinematics consist of 3 rotary and 1 translatory NC axes in the tool. Tool length compensation takes place in the Z axis. All rotary axes are C axes.

Axis configuration in the NC channel
Axis identifier	X, Y, Z, C (C1, C2, Z, C3)
Axis index	0, 1, 2, 3
Kinematic structure
	Tool axes	Workpiece axes
NC axes	X,Y, Z, C	-

SCARA kinematics in zero position (C1=0, C2=0, C3=0, HD8=0)

SCARA works as a left-handed or right-handed robot depending on the angular position of robot joint 2 (C2). The machine axis position before selecting the transformation therefore decides whether SCARA is positioned as a left-handed or right-handed robot. A change can be made from left-handed to right-handed robot when the kinematic transformation is inactive.

HD7 can be used to define the reference of the robot joint (C2).

In the default case of HD7 = 0 C2 refers to the angle between the extension of the first arm and the second arm. In the case of HD7 = 1 C2 refers to the angle between the X axis and the second arm.

HD8 is a rotary offset of C2. This permits the description of a zero position of the kinematics where the SCARA is not completely stretched out but is angled in the second joint. HD8=0 is the default.

HD7 = 0 (default)

HD7 = 1

Right-handed robot

Left-handed robot

Offset data of kinematics

HD offset	param[i]	Description	Unit
HD1	0	Tool length offset in Z direction	1.0 E-4 mm
HD2	1	Length offset from joint 1 to joint 2	1.0 E-4 mm
HD3	2	Length offset joint 2 to rotary axis C3	1.0 E-4 mm
HD4	3	X offset origin C1 axis	1.0 E-4 mm
HD5	4	Y offset origin C1 axis	1.0 E-4 mm
HD6	5	Rotary offset C1 axis	1.0 E-4°
HD7	6	Calculate reference of the robot joint for C2 0 = C2 as an offset of C1 (default) Calculate 1 = C2 as an angle to the X axis	[ - ]
HD8	7	Rotary offset C2 axis	1.0 E-4°