How to Build an Arduino Robot that Cleans Your House for Under $50

Introduction

Building an affordable robot that can clean your house may sound complicated, but it's actually quite achievable with some basic DIY skills and the right components. In this guide, I'll walk through the complete process of constructing a cleaning robot using an Arduino microcontroller and other low-cost parts for under $50.

What You'll Need

To build your budget cleaning bot, you'll need the following core components:

• Arduino Uno - The programmable microcontroller that serves as the robot's brain. Costs around $10.

• Motor driver - Allows the Arduino to control DC motors. Can get a basic one for $2-5.

• DC motors - Provide locomotion. Salvaged toy motors work well. You'll want at least 2. ~$5 each.

• Wheels - Attached to the motors to move the robot. Can reuse from toys. Around $3-5 per pair.

• ** ultrasonic sensor** - Detects obstacles. Can find for $2-3.

• Servo motor - For controlling sweeping motions. Get a small one for under $5.

• Batteries - Power the motors. 4 x AA batteries work fine.

• Chassis - The frame or body of the robot. Can be made from cardboard, wood, plastic.

• Cable ties and tape - To mount components to the chassis.

• Jumper wires - For connecting the components.

That covers the essential parts. With some scavenging and bargain hunting, you can source everything for $40-50.

Constructing the Chassis

The chassis provides the structure of the robot. It needs to be sturdy yet lightweight.

An easy, inexpensive option is using thick cardboard. Cut out two squares for the top and bottom decks, then notch and bend a couple of pieces to make the side walls. Use tape to hold everything together.

Leave gaps for attaching the wheels and sweeping servo. The exact dimensions aren't too important. About 12" x 12" for the base is a good size. Just make sure the walls are tall enough to mount all the components.

Mounting the Motors and Wheels

The drive motors will control the robot's movements.

To mount them, first disassemble the motors from any toys they were scavenged from. Use screws or cable ties to attach a motor to each side near the back.

Position them so the axles face outwards. Then press fit each wheel onto the motor shafts. The wheels should be wide enough for stability, with traction around the edges.

Make sure the wheels can spin freely without scraping against the chassis. Some spacer washers may help adjust the fit.

Adding the Servo and Sensors

Let's move on to mounting the other external components:

• The servo motor will sweep a brush or duster back and forth for cleaning. Install it near the front facing forward.

• The ultrasonic sensor needs to be angled outwards from the front to detect obstacles. Use some cardboard brackets to hold it in position.

• The Arduino can be secured to the top deck towards the back. Use some foam tape to prevent shifting.

• Lastly, install the batteries in the space between the Arduino and drive motors. This helps lower the center of gravity.

Wiring up the Electronics

With the physical construction complete, it's time to wire everything together electrically:

• Connect the drive motors to the motor driver, then wire the driver to the Arduino's PWM pins. This allows speed control.

• The servo gets wired directly to a PWM pin on the Arduino.

• The ultrasonic sensor has four pins - 5V power, ground, trigger, and echo. Hook these up to the matching pins on the Arduino.

• Finally, use the jumper wires to connect the batteries to the Vin and Gnd pins on the Arduino.

Use the Fritzing diagram below as a reference while connecting all the components. Pay close attention to the positive and negative terminals.

Programming the Arduino

The last step is uploading code to the Arduino so it can operate the robot.

The program needs to:

• Read distance data from the ultrasonic sensor
• Adjust motor speeds to move forward or turn
• Sweep the servo side-to-side for cleaning motions
• Loop continuously through these operations

While the exact code is too long to show here, the key functions it needs are:

c
readUltrasonic() // get distance to obstacles
setMotorSpeeds() // control forward/turning speed
sweepServo() // move servo side to side
loop() {
distance = readUltrasonic()
adjustMotorSpeeds(distance)
sweepServo()
}

Many sample sketches are available online for the main program logic. With some trial and error tweaking, you can get the bot vacuuming your floors autonomously.

Conclusion

Building a fully-functional cleaning robot for under $50 is definitely doable with an Arduino and basic DIY skills. The most important steps are:

• Constructing a sturdy chassis from cardboard and taping components in place
• Wiring up the DC motors, servo, ultrasonic sensor and Arduino properly
• Programming the Arduino to read sensors, control motion and automate cleaning

While it requires some effort, the end result is an economical DIY cleaning bot you can customize and upgrade. With thrifty sourcing of parts and creative coding, you'll soon have your own autonomous floor vacuuming robot!