TOPIC OF THE PROJECT: FLOOR CLEANING ROBOT

Team members: Adviti Mishra and Karan Kapoor

Abstract: The robot being designed by the authors of this report is a floor cleaning robot. What distinguishes the robot being designed from professionally designed floor cleaning robots like Roomba is that the cost of the materials used in this project evaluate to around 2,000 INR while robots available out there cost a minimum of 20,000 INR. Mopping the floor is often a tedious task especially for old people who live by themselves and have no help. The robot has been built to address this problem using materials available readily in mechanical stores and an Arduino board. This report contains the rationale behind choosing this project, the underlying concepts that are used, the hypothesis, expected outcomes, the circuit diagram, and the algorithm behind the robot followed by a conclusion where the efficacy of the robot, problems faced, and suggestions on optimizing the project further will be outlined.

Introduction: The issue that ultimately moved the authors to design this robot is the fatigue that people feel on mopping the floors manually. Therefore, the authors were incentivized to design a robot to address this problem while keeping in mind the cost of the project. The materials used are relatively cheap and are readily available in hardware stores. Furthermore, this project also aims to provide the same type of cleanliness like a professionally designed floor cleaning robot but at a lower cost. The authors are working towards achieving this outcome through software and hardware specializations.

Body:

The Robot is based on a metallic chassis with four wheels – two at the back that are equipped with motors and two at the front that are just connected via an axle. Towards the front end of the robot, an Ultra-Sonic sensor is attached below the metallic plate of the chassis and a 12 Volt Rechargeable Battery is attached above the chassis. Towards the back end of the Robot is a plastic bottle and below that is a dripper that will drip water onto the floor for cleaning. Just behind the dripper is the attachment of a rod that has a servo motor at its other end, connected to a cloth. The 12 Volt Battery, the Ultra-Sonic Sensor, the motors for the two wheels and the Servo Motor are all connected via jumper cables to the Arduino Board that is placed between the Water Bottle and the Plastic Tank.

Figure 1: a Schematic Diagram created by the authors illustrating how and in which port each and every appliance is connected along with the function of each appliance.

The code has a condition for the distance between the ultrasonic sensor and an obstacle. If the distance is lesser than or equal to 20cm, then motor 1 moves forward and motor 2 moves backward, causing the robot to turn around by 180 degrees. If the distance is not lesser than or equal to 20cm, then motor 1 and motor 2 move forward, causing the robot to move forward in a straight line. Thus, the algorithm for conditional input helps the robot turn around and clean the next stretch of floor after approaching a wall.

Figure 2: A diagram for the algorithm for conditional input created by the authors

Figure 3: A diagram for the algorithm for general output created by the authors showing important values

In order to avoid direct contact of the Arduino board with the metallic chassis, the authors have pasted cardboard on top of the chassis using hot glue. Another precaution taken to prevent the water from coming in contact with the robot is the use of a plastic extension rod. This rod has been designed on Fusion 360 and will be 3-D printed. A servo motor will be attached at the end of the rod to which a cloth will be attached that will rotate according to the code written. In order to ensure the stability of the motor and the cloth, the extension rod was 3-D printed rather than cut out of cardboard (which could possibly get wet as well).

Ultrasonic sensor

wheel

Motor

Battery

Picture 1: A picture of the back end of the robot taken by the authors. (Work in progress)

Front wheel

Arduino board

Picture 2: A picture of the robot taken from the top by the authors. (Work in progress)

Conclusion: The report above presents the underlying principles of the robot. The authors faced various unforeseen problems while designing the robot. Approximately a month after having handled the robot, the chassis of the robot had become bent possibly due to storage at a wrong angle. The authors had to disassemble the initial robot and reassemble it again with a new chassis- a bigger one. This proved to be a blessing in disguise since the authors found the bigger chassis easier to work with in terms of putting everything together. Furthermore, the code initially had a problem because of which the robot used to randomly turn around. The authors managed to debug the code and re calculate the distance the robot required to turn around. The robot is still being built but it successfully performs all the functions it has been programmed to in terms of moving in a straight line, sensing an obstacle, and turning around. This project could be optimized further by somehow adding a signal that beeps when the water in the bottle that is going to be attached is about to run out. Furthermore, a glass box or a protective transparent cover can be screwed into the chassis around the batter and the Arduino board to further protect it from water and destruction. The box can be removable in order to replace the battery when required.

Citations: The picture in figure 1 has been taken from Google. Pictures 1 and 2 have been taken by the authors