Timeline:

Libbot - A book organizing robot for library

Libbot is a low-cost and fully autonomous robot that has been designed and developed to help in management of a library. The robot is able to perform the basic function of scanning books, finding the right location for placing a book and properly placing the book to its allotted shelf with minimal human intervention.

Mechanical Design

The mechanical layout of the robot majorly consists of four subsystems: book-gripping sub-system that uses a slider-crank mechanism with a gripper; riser subsystem that uses scissor-lift mechanism with lead screw for the force of lift; chassis - forms the base of the robot; book holder and L-separator. The robot uses four-wheel skid steer drive mechanism for locomotion. Star-wheels (each of them has three wheels, thus total = 12 wheels) has been proposed for stair-climbing.

Electronic Module Design

Power:

Two Li-Po batteries with a combine potential 22.2V have been used to power the robot.

Sensors:

Barcode scanner(for scanning books), pressure sensors (for grippers), Rotary encoders, Raspberry Pi-Cam(for line following) and RFIDs.

Actuators:

High-powered bipolar stepper motors for actuating the scissor-lift mechanism, servo-motors to actuate crank-shaft mechanism and change the orientation of book, DC Motors for locomotion and linear actuators.

Interfacing:

Raspberry Pi 2 has been used as the central controller. It communicates with one Arduino MEGA board and also sends control commands to the locomotion actuators.

Control Algorithm Design

Tree for library: A tree has been setup to map all the shelves of the library from a starting point. The nodes of the tree are unique and physically represented by RFID tags.

Scanning and Path Planning: Books are scanned and shortest route based on RFID tags are planned. After planning, rasp-pi gives commands to Arduino. Rasp-pi cam is used for straight line following and a PID control loop on magnetostators and encoder motors has been used for turning motion.

Book Placement in shelf: Book from the holder is tilted to separate it from stack –> gripper grips the book –> scissor-lift rises to desired rack –> book gripper turns towards rack –> crank extends to place the book –> system retracts back to it original position.

A complete cost analysis was done and it was estimated that the robot could be manufactured with INR 39,976.

TODO: Add images

Link to the paper