3. User Interface:

The PC Interface program being developed allows for multiple input forms:• Direct G-Code entry• CAD file feed (converted to G-Codes by CAM module)• Voice Input (co-ordinates) , recognition by software, and then conversion to G-Code• Manual Control (via Joystick or on screen buttons)

STATIC CONTROL of ARDUINO - The complete code is sent to Arduino once and for allDYNAMIC CONTROL OF ARDUINO - Code is sent in real time and in continuous format for live control

In either of the cases, the PC serves as the final level of control the various input forms, and converts them to G-Codes. The Arduino receives only direct movement instructions for various pins

Design of Tabletop CNC machine with Variable User InterfaceSaurabh Gujarathi 1 , Vedant Prusty 2 , Kirti Kuchimanchi 3 , Sankarshan Bangaloree 4

Department of Mechatronics Engineering, Manipal Institute of Technology, Manipal

2. Design of TVIC:

The Tabletop Variable Input CNC (TVIC) is being designed to accept input in the form of CAD models/direct G-codes/Manual Control or even Voice control, and convert these to Machine Instructions. The Router frame, made primarily from aluminum extrusions, is robust enough to handle loads due to various machining operations. The tool post makes use of a modified speed-controllable Dremel tool, which allows for multiple attachments, the final aim being to have the capability of drilling, milling, polishing, etc. on materials like aluminum, nylon and wood.

[Work Volume: 400x400x400mm ; Table Space: 750x750mm]

Four Nema 34 High-Torque Stepper Motors are used for 3-axis control, 1 each for X-Axis and Z-Axis and 2 for Y-Axis. Each motor with Four-input cables for Four-poles is connected to a motor driver (This

connection uses 0 – 24V level). The motor drivers in turn are connected to an Arduino, which serves as the local computer on the CNC frame. [Motor Driver Current Rating : 3A]

The Arduino accepts only control commands for the 12 pin output. (Four pins for each of the X and Z motors, and Four pins for two common connected Y Motors.)

Connection with CONTROL PC may use Serial cable between Arduino and PC (USB) , or wireless control using devices such as Raspberry Pi (Bluetooth/Wifi/IP access). The well-defined protocol for input to Arduino board allows for a variety of devices to be used, leaving the TVIC’s electronic system highly customizable

1. Objective:To develop an easy-to-use compact, tabletop CNC Router capable of accepting multiple forms of input , and harboring a user friendly interface.

State of the Art:• Modern day factory-produced CNC Routers are used for cutting various materials such as wood, composites, aluminum, etc. Generally available in 3-axis or 5-axis Motion Of application.• These often require two software applications—one program to make designs (CAD) and another to translate those designs into a 'G-Code' program of instructions for the machine (CAM)

However, these Routers demand expertise in the relevant software, and do not cater to a multiple user situation. Manual control programs may allow for speeding up process, but are commercially impractical.There is a need for a low-cost, compact & table top version which is able to accept input in multiple forms to cater to a research based environment where medium precision parts may be needed within minimum time and without programming expertise.

5. References:• Dual Purpose Desktop Machine – 3D Printer and CNC Milling (Austin Grieve, Kenneth Klingler, Miguel

Acuna, Pavel Ikonomov, and Jorge Rodriguez - Western Michigan University)• Research and Implement of Open CNC system (LONG You-xi, ZHU Chun-guang, SHENG De-jun - College

of Electromechanical Engineering & Automation)• A PC-based retrofitting toward CAD/CAM/CNC integration (Suk-Hwan Suh, Sung-Kee Noh, Yong-Jong

Choi)• CNC Machining Handbook: Building, Programming, and Implementation (Alan Overby)

4. Conclusion:

The TVIC provides for an optimized solution to producing accurate parts without specific programming knowledge, ideal for research based environment. Features like Voice control and manual control via on-screen buttons or joysticks allows it’s use by non-professionals. The integration of a standardized input protocol for the local computer, the Arduino, and the All-in-one PC interface promises to leave the TVIC as a highly customizable, and low-cost CNC Router solution.

Acknowledgements: Mr. Ishwar Bhiradi, Asst. Prof. Dept. of Mechatronics, MIT Manipal for his encouragement and inspiration ; Director, MIT Manipal for his support.This Project is to be partially funded by the Student Project Scrutiny Board (SPSB), MIT Manipal

For more information, please contact: Sankarshan Bangaloree <sankarshanbangaloree@gmail.com> ; Vedant Prusty <vedprix@gmail.com> ; Deptartment of Mechatronics, MIT Manipal

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Fig.2

Fig. 1

Fig. 3

Fig. 1 – CAD Design of the TVIC – 1 --------------- --------- Fig. 2 – Electronics Block/Control Diagram

Fig. 3 – PC Interface and Control ------