Mecademic Meca500 R3, Programming Manual

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18 Programming manual for Meca500 (for firmware 9.2.x)
TCP/IP COMMUNICATION
particularly useful when you need to displace certain joints a certain amount, but you do not know the
current joint position and wish to avoid having to use the command GetRtTargetJointPos .
Arguments
• ∆ θ
i
: the desired relative displacement of joint i ( i = 1, 2, ..., 6), in degrees. The value of the argument
can be positive, negative or even zero.
2.1.6 MoveJointsVel ( θ̇
1
, θ̇
2
, θ̇
3
, θ̇
4
, θ̇
5
, θ̇
6
)
This command makes the robot rotate simultaneously its joints with the specified joint velocities. All
joint rotations start and stop at the same time. The path that the robot takes is linear in the joint space,
but nonlinear in the Cartesian space. Therefore, the TCP path is not easily predictable ( Figure 12 ). With
MoveJointsVel
, the robot can cross singularities without any problem.
Arguments
• θ̇
i
the velocity of joint i ( i = 1, 2, ..., 6), in °/s. The admissible ranges for the joint velocities are as fol -
lows:
−150°/s ≤ θ̇
1
≤ 150°/s,
−150°/s ≤ θ̇
2
≤ 150°/s,
−180°/s ≤ θ̇
3
≤ 180°/s,
−300°/s ≤ θ̇
4
≤ 300°/s,
−300°/s ≤ θ̇
5
≤ 300°/s,
−500°/s ≤ θ̇
6
≤ 500°/s.
Note that the robot will decelerate to a full stop after a period defined by the command SetVelTimeout ,
unless another MoveJointsVel command is sent. Also, bear in mind that the MoveJointsVel command,
unlike position-mode motion commands, generates no motion errors when a joint limit is reached. The
robot simply stops slightly before the limit.
2.1.7 MoveLin( x , y , z , α , β , γ )
This command makes the robot move its end-effector, so that its TRF ends up at a desired pose
with respect to the WRF while the TCP moves along a linear path in Cartesian space, as illustrated
in Figure 13 . If the final (desired) orientation of the TRF is different from the initial orientation, the
orientation will be modified along the path using a minimum-torque path. However, the robot will not
accept the
MoveLin
command if the required end-effector reorientation is exactly 180°, because there
could be two possible paths.
With this command, normally, the initial and final robot postures have to be in the same configuration,
{ c
s
, c
e
, c
w
}. Only in some very peculiar cases, where the path passes exactly through a shoulder or
wrist singularity, and when the automatic posture configuration selection is enabled, a change in c
s
or c
w
, respectively, is possible (see Section 1.2.4 ). If the complete motion cannot be performed due to
singularities or joint limits, it will not even start, and an error will be generated.
If you specify a desired turn configuration, the
MoveLin
command will be executed only if the initial and
final robot positions have the same turn configuration as the desired one.