Application Number: 201911036156

Filing Date: 9 September 2019

Inventors: Mr. Anirudh Kumar Dr. Soumen Mandal Dr. Partha Bhattacharjee Mr. Saurav Halder Mr. Kalyan Chatterjee

Abstract:

The invention is related to development of a nano-positioning controller for micro-nano scale laser patterning machine. The controller houses ATMEL SAM3X8E ARM Cortex-M3 CPU based microcontroller and controls three linear stages (in X, Y and Z directions) driven by servo motor and laser head based system as centralized architecture. Data based motion commands are sent to the microcontroller from a single board computer (SBC) in form of binary strings using serial mode of communication. The microcontroller checks for validity of received data using cyclic redundancy check (CRC) and generate acknowledgement signal to the SBC. The micro controller receives position feedback signal from encoders connected to motor shaft compares it with motion command, propagates the motion error in a proportional integral control loop and generates control commands. The controller further generates three different pulses of varying frequencies and one pulse of constant frequency and varying duty cycle and sends them to three different motor drivers for controlling position and speed and laser head for controlling laser power respectively. The controller generates pulses of varying frequencies employing pulse state locking employing dedicated interrupt subroutines. The maximum straight line displacement error along each axis was limited to 10% in the displacement range 100 nm to 100 micro meter where the stages had a mechanical resolution of 100 nm or higher.

Patent Type: Filed

Place of Patent: India