Mecademic Meca500 R3, Programming Manual

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2 Programming manual for Meca500 (for firmware 9.2.x)
BASIC THEORy ANd dEfINITIONS
• BRF: Base reference frame . Static reference frame fixed to the robot base. Its z axis coincides with
the axis of joint 1 and points upwards, its origin lies on the bottom of the robot base, and its x axis
is normal to the base front edge and points forward.
• WRF: World reference frame . The main static reference frame coincides with the BRF by default. It
can be defined to correspond to the BRF using the SetWrf command.
• FRF: Flange reference frame . Mobile reference frame fixed to the robot's flange (the 20-mm disk with
threaded holes at the extremity of the robot, shown in Figure 1 b ). Its z axis coincides with the axis
of joint 6, and points outwards. Its origin lies on the surface of the robot's flange. Finally, when all
joints are at zero, the y axis of the FRF has the same direction as the y axis of the BRF.
• TRF: Tool reference frame . The mobile reference frame associated with the robot's end-effector. By
default, the TRF coincides with the FRF. It can be defined with respect to the FRF with the
SetTrf
command.
• TCP: tool center point . Origin of the TRF. (Not to be confused with the Transmission Control Protocol
acronym, which is also used in this document.)
Figure 2: Reference frames for the Meca500
1.1.4 Pose and Euler angles
Some Meca500 commands accept
pose
(position and orientation of one reference frame with respect
to another) as an input. In these commands, and in the Meca500 web interface, a pose consists of a
Cartesian position, { x , y , z }, and an orientation specified in Euler angles , { α , β , γ }, according to the mobile
XYZ convention (also referred to as RxRyRz). In this convention, if the orientation of a frame F
1
with
respect to a frame F
0
is described by the Euler angles { α , β , γ }, it means that if you align a frame F
m
with
frame F
0
, then rotate F m about its x axis by α degrees, then about its y axis by β degrees, and finally
about its z axis by γ degrees, the final orientation of frame F
m
will be the same as that of frame F
1
.
Figure 3 shows an example of specifying orientation using the mobile XYZ Euler angle convention. The
diagram on the right shows the black reference frame orientation with respect to the gray reference
frame with the Euler angles {45°, −60°, 90°}.