Smart Ride

Our favourite childhood toys meet modern technology! Smart Ride is an improved remote-controlled car that uses an ultrasonic sensor to map the room!

info

Author: Popovici Andra-Raluca

GitHub Project Link: https://github.com/UPB-PMRust-Students/project-andra-raluca-pop

Description

The car is controlled by means of a virtual remote control simulated in a web app. It uses an IOE-SR05 Ultrasonic Sensor to display the distance between the car and obstacles and aims to create a virtual map inside the web app.

Motivation

Since I was in primary school, my favourite toys were remote-controlled cars, which I've collected for several years. This project combines my childhood passion with modern technology and aims to make a more interesting, cooler remote control car suitable for all ages!

Architecture

Components

1. Raspberry Pi Pico 2W

• The brain of the system.
• Handles:
  • Wi-Fi communication using cyw43 driver
  • TCP server via embassy-net
  • GPIO-based control of motors and sensors
  • Real-time task management via embassy async runtime

2. Web App

• Runs in any browser on the same Wi-Fi network.
• Sends TCP commands to the Pico 2W ("forward", "backward", "left", "right", "stop", "distance", "map").

3. Web Server (Rust Firmware on Pico 2W)

• Accepts and parses TCP socket messages.
• Sends movement signals to motors and reads data from sensors.
• Responds with sensor readings or map history when requested.

4. Ultrasonic Sensor (IOE-SR05)

• Triggered via GPIO (PIN_7) and receives echo on PIN_6.
• Measures front-facing distance using echo timing.
• Used for mapping and collision awareness.

5. Motor Control (L298N via GPIO)

• Controlled through GPIO (PIN_2 to PIN_5) — no PWM used.
• Logic functions for movement:
  • forward() – move ahead
  • backward() – move back
  • left() / right() – turn
  • stop() – stop motion

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Communication Between Components

The architecture relies on coordinated communication between all components as follows:

From	To	Medium	Purpose
Web App	Pico 2W	Wi-Fi	Send movement/query commands via TCP socket
Pico 2W	L298N Motor Driver	GPIO	Control motor direction (IN1–IN4 logic levels)
Pico 2W	IOE-SR05 Sensor	GPIO	Send trigger and read echo (distance)
Pico 2W	Web App	TCP	Reply with sensor or mapping information

Log

Week 5 - 11 May

After establishing the final form of the project, I started my documentation by gathering information about the required hardware parts and necessary libraries. I configured the setup: I connected the Raspberry Pi Pico 1 for debugging to the target (Raspberry Pi Pico 2W) and used the provided lab repository. I also started working on the hardware pieces by cutting the base structure on which all the components will be glued. Then I connected the 2 DC motors to the L298N module and added their required functions to the code.

Week 12 - 18 May

This week, I finished the code and functions for the DC motors (final adjustments), created the basic function for the IOE-SR05 sensor and created the web app for the remote control, including the TCP server and http converter. In terms of harware, I finished the setup (wiring, fixing the ball caster that replaces the wheels in the back, fixing the sensor onto the acrylic plate).

Week 19 - 25 May

During the last week I customised the web app for the remote control, making it user-friendly and visually pleasing. I also finished the mapping logic and function and made the car show it in the web app as well as in the terminal.

Hardware

The car uses a Raspberry Pi Pico 2W microcontroller that manages motor control and sensor input. I included 2 motors with gearbox and attached wheels that allow movement in 4 directions (left, right, forward, backward) as well as stopping the movement when the user presses the " stop" button. An IOE-SR05 Ultrasonic sensor is attached in the front and used for distance measurement and mapping. It provides feedback for the user to help avoid obstacles. Finally, for debugging, a Raspberry Pi Pico 1 was as it helped in testing the hardware components and developing the source code.

Schematics

Bill of Materials

Device	Usage	Price
Raspberry Pi Pico W	Main microcontroller with Wi-Fi, runs Rust firmware	35 RON
Raspberry Pi Pico	Used for debugging during development	25 RON
DC Motor with Gearbox and Wheel x2	Motion and propulsion	11.90 RON x2 = 23.80 RON
IOE-SR05 Ultrasonic Sensor	Room mapping / obstacle detection	8.90 RON
L298N Motor Driver Module	Controls the motors with PWM and direction signals	13.90 RON
Breadboard 400 pins x2	Prototyping and wiring	7.90 RON x2 = 15.80 RON
Male-to-Male Jumper Wires	Wiring connections between modules	4.90 RON
Female-to-Female Jumper Wires	Wiring connections between modules	4.90 RON
3.7V Li-ion Rechargeable Battery x2	Powers the system (motors and/or controller)	19.99 RON x2 = 39.98 RON
Transparent Plexiglass Plate	Chassis base for mounting electronics and wheels	10.90 RON

| Total | | 182.98 RON |

Software

Software Libraries

Library / Crate	Description	Usage Example
embassy-executor	Async runtime for embedded Rust	Drives async main loop
embassy-rp	HAL for Raspberry Pi Pico boards	Access GPIOs, peripherals
embassy-time	Timing and delays	Timer::after_millis(100).await
embassy-net	TCP/IP networking stack	Runs a TCP server
embassy-usb	USB support (optional)	USB-related functions (if used)
cyw43	Driver for CYW43 Wi-Fi chip on Pico W	Connects to Wi-Fi
cyw43-pio	PIO backend used by CYW43	Enables PIO communication
defmt / defmt-rtt	Efficient logging and debugging via RTT	info!("message") in terminal
panic-probe	Panic handler for embedded Rust	Shows panic messages
embedded-io-async	Async I/O traits for sockets	Used for socket.write_all(...)
gpio::{Level, Input, Output}	Pin control for motors and sensors	Used for motor/sensor pins
fixed::traits::ToFixed	Numeric conversion to fixed-point	Converts float to fixed
static_cell	Safe global static memory management	Static memory for network stack

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Links

Masina Bluetooth - Exemplu Proiect PM