Description
Attention
On its own, the kinematic velocity limit is not a safety function.
To ensure T1 operation safety, the TCP velocity of the robot must additionally be monitored in a safety PLC.
The aim is to provide error-free control of a robot in T1 mode. It prevents the velocity monitor from reporting a velocity that is too high. This would result in the machine changing to an error state. This also applies to operation without active transformation (cf. Reduced velocity).
The velocity limit has the following properties:
- The limit acts in NC automatic and manual modes.
- When the limit is enabled via the HLI, the lowest velocity is used for all the set kinematics.
- The velocity override continues to act on the programmed velocity.
- One kinematic and one velocity can be specified for each limit.
Operating principle
The velocity limit calculates a Cartesian position using the forward transformation of the specified kinematic. This is then used in motion blocks to calculate the path velocity, provided it does not exceed the specified maximum velocity of the Cartesian motion.
When the tcp_velocity_limit control unit is set to TRUE, the new path velocity is applied to the maximum path velocity as an additional limit during interpolation.
The velocity limit function can be enabled either at program start or by the NC command #LIMIT ON[TCP_VEL …].
With the program start variant, the channel parameter limit.kin[i].active must be set to 1 (P-CHAN-00464).
In both cases, no errors should be made when programming the kinematic to be limited.
Notice
It is not permitted to perform an axis exchange when the TCP velocity limit function is active.
Notice
The TCP velocity limit is calculated by setting P-CHAN-00464 at program start..
Notice
The calculated limit value is used by setting the tcp_velocity_limit control unit.