By Hünkar Kemal Yurt, mechatronics system design engineer at VDL ETG

VDL ETG is responsible to develop precise mechatronic handler systems for lithography machines which contain several 3 DOF SCARA type robots. These robots are mainly responsible for moving the payload between the modules with desired accuracy under high environmental vibration loads.

Hünkar will elaborate on how to calculate the position accuracy of the payload for different scenarios, using a validated Computer Aided Engineering (CAE) model for both frequency and time domain accuracy calculations.
When it comes to the performance of the robot, structural flexibility, driveline details, dissipation & friction and controller design are crucial details for the accuracy.

By using the Flexible Multi-Body Dynamic (FMBD) simulation approach which allows to perform efficient simulations in both frequency and time domains, a high- fidelity model is created for the robots by considering all crucial details.

The FMBD model is validated with respect to the measurement data on the physical prototype, and now it is being used for frequency and time domain accuracy calculations for special working scenarios by including the controller dynamic.