E-CAM Clutch Types

The E-CAM clutch type determines how the slave axis initially synchronizes with the master axis when E-CAM control is started.

No Clutch Type

With the None clutch type, no clutch processing is performed. The slave axis is immediately synchronized with the master axis according to the master-slave position curve defined by the E-CAM table. Depending on the slave axis command position when ECAM is started, the slave axis may experience sudden motion.

Simple Catch Up Clutch Type

With the SimpleCatchUp clutch type, the slave axis “catches up” to the master-slave position curve defined by the E-CAM table using a trapezoidal profile.

When E-CAM control is started, an offset is added to the slave axis command position to prevent the slave axis from moving suddenly. This offset is gradually reduced at a rate following a trapezoidal profile. When the offset is reduced to 0, the slave axis will be synchronized to the master-slave position curve and the E-CAM operation can continue normally. The initial offset is equal to the distance between the command position immediately before starting E-CAM control and the initial command position after starting E-CAM control. The time it takes for the offset to be reduced to 0 is the time required to traverse the offset distance using a trapezoidal profile with the specified velocity and acceleration.

The simple catch up clutch type is illustrated below:

The master axis may be moved freely while the slave is executing the catch up motion. The slave axis command position each cycle will be calculated by the master-slave position curve of the E-CAM, but will have an additional offset. The rate that the offset is reduced each cycle is not affected by the slave or master positions. The offset will be reduced to 0 in the same amount of time as the case where the master axis is not moving.

The simple catch up clutch type when the master axis is moving in the positive direction is illustrated below: