John: /* Design Goals */

2025-10-11T20:29:15Z

Design Goals

← Older revision		Revision as of 20:29, 11 October 2025
Line 18:		Line 18:
	SimpleBot was designed with BRS's core mission in mind:		SimpleBot was designed with BRS's core mission in mind:

	* '''~~Optical odometry and line following~~''' - SimpleBot is a demonstrator for dead reckoning and line maze problems, required study for all entry-level roboticists.		* '''Enable Real-World Use Cases''' - SimpleBot is a demonstrator for dead reckoning and line maze problems, required study for all entry-level roboticists.
	* '''Design and build custom robots''' - 3D-printed chassis with modular sensor mounts		* '''Design and build custom robots''' - 3D-printed chassis with modular sensor mounts
	* '''Lower the barrier to entry''' - Under $20 total cost with ~~all batteries~~ included		* '''Lower the barrier to entry''' - Under $20 total cost with Optical odometry and line following sensors included.
	* '''Teach robotics fundamentals''' - Every component serves an educational purpose		* '''Teach robotics fundamentals''' - Every component serves an educational purpose

John: /* Design Goals */

2025-10-11T20:27:27Z

Design Goals

← Older revision		Revision as of 20:27, 11 October 2025
Line 18:		Line 18:
	SimpleBot was designed with BRS's core mission in mind:		SimpleBot was designed with BRS's core mission in mind:

	* '''~~Build automatons, not remote controlled toys~~''' - SimpleBot ~~makes decisions~~ and ~~follows lines autonomously~~		* '''Optical odometry and line following''' - SimpleBot is a demonstrator for dead reckoning and line maze problems, required study for all entry-level roboticists.
	* '''Enable real-world use cases''' - ~~Optical odometry and line following are practical navigation techniques~~
	* '''Design and build custom robots''' - 3D-printed chassis with modular sensor mounts		* '''Design and build custom robots''' - 3D-printed chassis with modular sensor mounts
	* '''Lower the barrier to entry''' - Under $20 total cost with all batteries included		* '''Lower the barrier to entry''' - Under $20 total cost with all batteries included

John: Claude edited based on my notes, prompt, and SimpleBot code repository

2025-10-11T16:18:18Z

Claude edited based on my notes, prompt, and SimpleBot code repository

New page

{{Robot
| name = SimpleBot
| image = simplebot.jpeg
| caption = SimpleBot - BRS's first robot design
| use_case = Educational robot for learning line following, optical odometry, and basic robotics
| microcontroller = [[Raspberry Pi Pico]] or [[Raspberry Pi Pico W]]
| sensors = 2× [[Infrared Line Detector]], 2× Optical Encoders (custom), optional [[MPU6050]] IMU, optional nRF24L01 radio
| power = 4× AA batteries (6V nominal) via [[MP1584]] buck converter (3.3V output)
| pcb = [[BRS Differential Drive Robot Control Board]] (through-hole assembly)
| cost = '''Under $20''' (with batteries)
| repository = [https://github.com/Bespoke-Robot-Society/simplebot GitHub Repository]
}}

'''SimpleBot''' is the Bespoke Robot Society's original robot design, created for students, educators, and cost-conscious makers. It's a fully functional {{Wikipedia|Differential_wheeled_robot|differential drive robot}} that demonstrates core robotics concepts including motor control, sensor integration, and autonomous navigation.

== Design Goals ==

SimpleBot was designed with BRS's core mission in mind:

* '''Build automatons, not remote controlled toys''' - SimpleBot makes decisions and follows lines autonomously
* '''Enable real-world use cases''' - Optical odometry and line following are practical navigation techniques
* '''Design and build custom robots''' - 3D-printed chassis with modular sensor mounts
* '''Lower the barrier to entry''' - Under $20 total cost with all batteries included
* '''Teach robotics fundamentals''' - Every component serves an educational purpose

== Overview ==

SimpleBot is based on commonly available "Arduino Smart Car" components (motors, wheels, battery holder) combined with a custom 3D-printed chassis and optional custom PCB. The robot can be built three ways:

# '''Breadboard Version''' - Wire everything on a breadboard (fastest to prototype)
# '''Protoboard Version''' - Solder components to perfboard (more permanent)
# '''Custom PCB Version''' - Use the [[BRS Differential Drive Robot Control Board]] (most compact)

All three versions run the same code and have identical functionality.

== Capabilities ==

=== Line Following ===
Two [[Infrared Line Detector|infrared line detectors]] mounted under the chassis track a black line on a white surface (or vice versa). The robot adjusts its motor speeds to stay centered on the line.

=== Optical Odometry ===
Custom encoder circuits use LEDs and photoresistors to count pulses from slotted wheels attached to the motors. This allows the robot to measure distance traveled and perform [[dead reckoning]].

=== Motor Control ===
The [[TB6612FNG]] dual H-bridge provides independent speed and direction control for both wheels via PWM signals from the Pico.

=== Expansion Ready ===
The PCB includes headers for:
* '''MPU6050''' 6-axis IMU (accelerometer + gyroscope) via I²C
* '''nRF24L01''' 2.4 GHz radio module via SPI
* '''4× sensor headers''' for additional sensors (3.3V + GND + GPIO)
* '''Analog/digital breakout headers''' for custom additions

== Hardware ==

=== Base Components ===

{| class="wikitable"
! Component !! Description !! Qty !! Est. Cost
|-
| Arduino Smart Car Kit || 2× TT motors with wheels, encoder discs, battery holder, power switch, caster wheel || 1 || $6
|-
| [[Raspberry Pi Pico]] || Microcontroller board (or Pico W for Wi-Fi) || 1 || $4
|-
| [[TB6612FNG]] Module || Dual H-bridge motor driver || 1 || $3
|-
| [[MP1584]] Module || Buck converter (6V → 3.3V) || 1 || $1
|-
| [[Infrared Line Detector]] || Line following sensors || 2 || $1
|-
| [[LM393]] IC || Dual comparator for optical encoders || 1 || $0.25
|-
| Resistors, LEDs, photoresistors || Encoder circuit components || Set || $1
|-
| 4× AA Batteries || Power supply (1.5V each = 6V total) || 4 || $2
|-
| 3D Printed Parts || Chassis, motor mounts, sensor mounts || Set || $2 (filament)
|-
| '''Total''' || || || '''~$20'''
|}

=== PCB Options ===

* '''[[BRS Differential Drive Robot Control Board]]''' (Through-Hole) - $5-10 for 5 PCBs from JLCPCB, ~$5 in components
* '''Breadboard/Perfboard''' - Cheaper but less compact

== Mechanical Design ==

SimpleBot uses a modular 3D-printed chassis with several key features:

=== Chassis Modules ===

* '''Main Chassis Plate''' - Central platform with mounting points for all modules
* '''Battery Block''' - Secures 4× AA battery holder with velcro strap retention
* '''Caster Assembly''' - Front-mounted caster wheel with adjustable height
* '''Motor Mounts''' - Dovetail attachment system for easy motor positioning
* '''Sensor Rail''' - Underside mounting for adjustable line sensors

All STL files and the FreeCAD source are available in the [https://github.com/Bespoke-Robot-Society/simplebot GitHub repository].

=== Assembly ===

See the detailed [[SimpleBot Assembly Guide]] (or [https://github.com/Bespoke-Robot-Society/simplebot/blob/master/ASSEMBLY_GUIDE.md GitHub version]) for step-by-step mechanical assembly instructions with images.

== Electronics ==

=== Circuit Design ===

The electronics integrate:
* Power regulation (6V battery → 3.3V via buck converter)
* Motor control (TB6612FNG dual H-bridge)
* Optical encoder circuits (LM393 comparators)
* Sensor interfaces (line detectors, IMU, radio)
* GPIO expansion (analog and digital headers)

=== PCB Design ===

See the detailed [[SimpleBot PCB Guide]] (or [https://github.com/Bespoke-Robot-Society/simplebot/blob/master/PCB_GUIDE.md GitHub version]) for:
* Full schematic
* PCB layout views
* Component placement
* Assembly instructions
* Gerber files for manufacturing

The PCB uses '''through-hole components''' for easy hand-soldering, making it ideal for educational builds and beginners.

== Software ==

SimpleBot runs '''MicroPython''' on the [[Raspberry Pi Pico]], making it accessible to beginners while providing full control over hardware.

=== Programming ===

# Install [https://thonny.org/ Thonny IDE] or use any MicroPython-compatible editor
# Connect Pico via USB
# Copy Python files from the repository to the Pico
# Edit configuration for your specific hardware
# Run and test!

=== Code Structure ===

The SimpleBot code is organized into modular files:
* '''motor.py''' - Motor control class with PWM speed control
* '''encoder.py''' - Optical encoder pulse counting
* '''line_sensor.py''' - Line detector interface
* '''robot.py''' - High-level robot control (drive forward, turn, etc.)
* '''main.py''' - Main program loop

=== Example Code ===

<syntaxhighlight lang="python">
from robot import SimpleBot
import time

# Initialize robot
bot = SimpleBot()

# Drive forward 30cm using odometry
bot.drive_distance(30) # cm

# Follow a line
while True:
left, right = bot.read_line_sensors()

if not left and not right:
bot.forward(speed=50) # Both on white - go straight
elif left:
bot.turn_right(speed=40) # Left on line - turn right
elif right:
bot.turn_left(speed=40) # Right on line - turn left

time.sleep(0.01)
</syntaxhighlight>

Full code examples available in the [https://github.com/Bespoke-Robot-Society/simplebot GitHub repository].

== Build Paths ==

Choose the path that matches your skill level and available resources:

=== Path 1: Buy Everything (Easiest) ===

'''Best for:''' Complete beginners, classrooms

# Purchase all components from the bill of materials
# 3D print the chassis parts (or use a print service)
# Order the pre-assembled PCB (or use breadboard)
# Follow assembly guide
# Upload code and go!

'''Time:''' 2-4 hours assembly + printing time

=== Path 2: Solder It Yourself (Learning) ===

'''Best for:''' Learning electronics, gaining soldering experience

# Purchase components and blank PCB
# Order Gerber files from JLCPCB (~$2 for 5 PCBs)
# Learn through-hole soldering techniques
# Assemble PCB step by step
# Integrate into 3D-printed chassis
# Upload code and test!

'''Time:''' 4-8 hours including soldering practice

=== Path 3: Design Your Own (Advanced) ===

'''Best for:''' Experienced makers, custom requirements

# Use SimpleBot as a reference design
# Modify the FreeCAD chassis for your needs
# Adapt the PCB design in KiCad
# Add custom sensors or actuators
# Create your own robot variant!

'''Time:''' Unlimited - this is your custom project!

== Learning Outcomes ==

Building and programming SimpleBot teaches:

=== 3D Printing ===
* Printing functional mechanical parts
* Working with heat-set inserts
* Designing for printability

=== Electronics ===
* Motor control with H-bridges
* Sensor interfacing (analog and digital)
* Power regulation with buck converters
* PCB assembly (through-hole soldering)

=== Software ===
* MicroPython programming
* PWM for motor speed control
* Interrupt-driven encoder counting
* Sensor polling and decision making
* PID control (optional advanced topic)

=== Robotics Concepts ===
* Differential drive kinematics
* Optical odometry for position tracking
* Line following algorithms
* Dead reckoning navigation
* Sensor fusion (with IMU)

== Variations ==

=== SimpleBot Mini ===
A smaller version designed to fit standard micromouse mazes (under development).

=== SimpleBot Pro ===
Enhanced version with additional sensors, faster motors, and ROS integration (future development).

=== Community Variants ===
See [[Build Logs:SimpleBot]] for community members' custom builds and modifications.

== Limitations ==

SimpleBot is designed as an educational platform, so it has intentional limitations:

* '''Speed''' - Deliberately slow for safety and learning
* '''Maze Size''' - Too large for standard micromouse mazes (see SimpleBot Mini)
* '''Terrain''' - Designed for flat, smooth surfaces only
* '''Line Following''' - Two-sensor configuration is simple but less robust than arrays

These limitations are features, not bugs - they provide opportunities for learning and improvement!

== Next Steps After Building SimpleBot ==

Once you've built and programmed SimpleBot, consider:

# '''Master line following''' - Optimize your code for speed and accuracy
# '''Add the IMU''' - Implement heading-based navigation
# '''Add the radio''' - Control remotely or implement swarm behavior
# '''Design custom sensors''' - Add ultrasonic, IR distance, or other sensors
# '''Build a maze''' - Create line-following challenges
# '''Modify the chassis''' - Add a pen holder for drawing robots
# '''Teach others''' - Document your build and help newcomers

== Resources ==

* '''[https://github.com/Bespoke-Robot-Society/simplebot GitHub Repository]''' - CAD files, code, PCB designs
* '''[[SimpleBot Assembly Guide]]''' - Step-by-step mechanical assembly
* '''[[SimpleBot PCB Guide]]''' - Electronics and PCB information
* '''[[Raspberry Pi Pico]]''' - Microcontroller documentation
* '''[[BRS Differential Drive Robot Control Board]]''' - PCB details

== See Also ==

* [[Differential Drive]] - Theory behind two-wheeled robots
* [[Optical Odometry]] - Measuring distance with encoders
* [[Line Following]] - Algorithms and techniques
* [[Motor Control]] - PWM and H-bridge operation
* [[3D Printing for Robotics]] - Designing and printing robot parts

== Community ==

Share your SimpleBot build:
* Post photos and videos on the [[Discord]]
* Create a [[Build Logs:SimpleBot|build log]] on the wiki
* Submit improvements via pull request on GitHub
* Help answer questions from new builders

[[Category:Robot]]
[[Category:Educational]]
[[Category:Line Following]]
[[Category:Differential Drive]]

SimpleBot - Revision history

John: /* Design Goals */

John: /* Design Goals */

John: Claude edited based on my notes, prompt, and SimpleBot code repository