{"id":19671453,"url":"https://github.com/lasithaamarasinghe/analog-wall-follow-robot","last_synced_at":"2026-03-04T06:33:05.717Z","repository":{"id":217577238,"uuid":"744266689","full_name":"LasithaAmarasinghe/Analog-Wall-Follow-Robot","owner":"LasithaAmarasinghe","description":"This analog wall follow robot is developed for the semester 3 project under EN2091: Laboratory Practice and Projects.","archived":false,"fork":false,"pushed_at":"2024-06-23T07:13:47.000Z","size":52242,"stargazers_count":6,"open_issues_count":0,"forks_count":0,"subscribers_count":1,"default_branch":"main","last_synced_at":"2025-02-27T04:50:14.682Z","etag":null,"topics":["altium-designer","analog-electronics","l298-motor-controller","n20-motors","pid-algorithm","sharp-ir-sensor","smd","solidworks","tl084cn","wall-following"],"latest_commit_sha":null,"homepage":"","language":"HTML","has_issues":true,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":"mit","status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/LasithaAmarasinghe.png","metadata":{"files":{"readme":"README.md","changelog":null,"contributing":null,"funding":null,"license":"MIT-LICENSE.txt","code_of_conduct":null,"threat_model":null,"audit":null,"citation":null,"codeowners":null,"security":null,"support":null,"governance":null,"roadmap":null,"authors":null,"dei":null,"publiccode":null,"codemeta":null}},"created_at":"2024-01-17T00:12:21.000Z","updated_at":"2024-06-23T07:13:49.000Z","dependencies_parsed_at":"2024-06-23T08:39:53.256Z","dependency_job_id":null,"html_url":"https://github.com/LasithaAmarasinghe/Analog-Wall-Follow-Robot","commit_stats":null,"previous_names":["lasithaamarasinghe/analog-wall-follow-robot"],"tags_count":0,"template":false,"template_full_name":null,"purl":"pkg:github/LasithaAmarasinghe/Analog-Wall-Follow-Robot","repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/LasithaAmarasinghe%2FAnalog-Wall-Follow-Robot","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/LasithaAmarasinghe%2FAnalog-Wall-Follow-Robot/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/LasithaAmarasinghe%2FAnalog-Wall-Follow-Robot/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/LasithaAmarasinghe%2FAnalog-Wall-Follow-Robot/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/LasithaAmarasinghe","download_url":"https://codeload.github.com/LasithaAmarasinghe/Analog-Wall-Follow-Robot/tar.gz/refs/heads/main","sbom_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/LasithaAmarasinghe%2FAnalog-Wall-Follow-Robot/sbom","scorecard":null,"host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":286080680,"owners_count":30074176,"icon_url":"https://github.com/github.png","version":null,"created_at":"2022-05-30T11:31:42.601Z","updated_at":"2026-03-04T05:31:57.858Z","status":"ssl_error","status_checked_at":"2026-03-04T05:31:38.462Z","response_time":59,"last_error":"SSL_connect returned=1 errno=0 peeraddr=140.82.121.5:443 state=error: unexpected eof while reading","robots_txt_status":"success","robots_txt_updated_at":"2025-07-24T06:49:26.215Z","robots_txt_url":"https://github.com/robots.txt","online":false,"can_crawl_api":true,"host_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub","repositories_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories","repository_names_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repository_names","owners_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners"}},"keywords":["altium-designer","analog-electronics","l298-motor-controller","n20-motors","pid-algorithm","sharp-ir-sensor","smd","solidworks","tl084cn","wall-following"],"created_at":"2024-11-11T17:08:50.687Z","updated_at":"2026-03-04T06:33:05.671Z","avatar_url":"https://github.com/LasithaAmarasinghe.png","language":"HTML","funding_links":[],"categories":[],"sub_categories":[],"readme":"# Analog Wall Following Robot\nThis is a group project done under the module EN2091 - Laboratory Practice and Projects, Semester 3, Department of Electronic and Telecommunication Engineering, University of Moratuwa. \n\n## Introduction\n\n*  Wall following robot is a robot that follows a wall and travels keeping a constant distance from the wall. \n*  Wall following is a common task in many robotics competitions.\n*  But the interesting point is our project was to build a robot that travels on the centerline between two walls using only analog electronics.\n*  That means we couldn’t use microcontrollers according to the [guidelines](https://github.com/LasithaAmarasinghe/Analog-Wall-Follow-Robot/blob/main/Project_Guidelines.pdf).\n\n![IMG-20231206-WA0097](https://github.com/LasithaAmarasinghe/Analog-Wall-Follow-Robot/assets/106037441/241e426e-1c0c-4cf3-a58a-3e9705a20f41)\n\n## Working Concept\n\n*  Two sharp IR sensors measure the distance from the robot to the side walls.\n*  The difference between the sharp IR sensor values is taken as the error signal and fed into a PID control circuit.\n*  The PID output signal is fed to the adder and subtractor circuits.\n*  The PID output and a comparator circuit generate two PWM signals with varying duty cycles.\n*  Then using the motor driver, PWM signals are fed to the left and right wheels.\n*  The robot tracks the walls and travels on the centerline between walls.\n*  Additionally we added another sharp IR sensor to the front of the robot to control the speed of the robot.\n*  The measured distance is compared with a predefined distance and the difference is taken as the error signal.\n*  The error signal is fed to a PID control circuit.\n*  A PWM signal is generated using the PID output and a comparator circuit.\n*  This PWM signal acts as the Base speed of the robot.\n*  Consequently the additional sharp IR sensor will vary the car's speed accordingly.\n\n![image](https://github.com/LasithaAmarasinghe/Analog-Wall-Follow-Robot/assets/106037441/49f70bd2-af03-46a3-9955-452a3b607f5d)\n\n## Sub Circuits and Tasks\n\n* [Instrumentation Amplifier](https://github.com/LasithaAmarasinghe/Analog-Wall-Follow-Robot/blob/main/Circuits/Instrumentation%20Amplifier.jpg)- Reduce noise in Sharp IR sensor outputs and amplify signals\n* [PID circuit](https://github.com/LasithaAmarasinghe/Analog-Wall-Follow-Robot/blob/main/Circuits/PID.jpg)- Control the error signal smoothly using feedback\n* [Adder \u0026 Subtractor](https://github.com/LasithaAmarasinghe/Analog-Wall-Follow-Robot/blob/main/Circuits/Adder%20%26%20Substractor.jpg)- Generate two PWM signals with varying duty cycles according to PID output\n\t* Motor 1= base speed + PID output\n\t* Motor 2= base speed - PID output\n* [PWM circuit](https://github.com/LasithaAmarasinghe/Analog-Wall-Follow-Robot/blob/main/Circuits/PWM.jpg)- Generate two different comparator voltages for the two motors\n\t* Motor 1 duty cycle ∝ base speed + PID output\n\t* Motor 2 duty cycle ∝ base speed - PID output\n* [Voltage Regulator](https://github.com/LasithaAmarasinghe/Analog-Wall-Follow-Robot/blob/main/Circuits/Voltage%20Regulator.png)- To get 3.3V and 5V for required parts accordingly\n* [Speed Selector](https://github.com/LasithaAmarasinghe/Analog-Wall-Follow-Robot/blob/main/Circuits/Speed%20Selector.png)- Manually control the base speed\n\n## Hardware Specifications\n\n* [TL084CN ICs](https://github.com/LasithaAmarasinghe/Analog-Wall-Follow-Robot/blob/main/data%20sheets/TL084CN_GeneralPurposeAmplifier.pdf)\n* Two [Sharp IR Sensors](https://github.com/LasithaAmarasinghe/Analog-Wall-Follow-Robot/blob/main/data%20sheets/Sharp%20IR%20Sensor.pdf) \n* Two [N20 Motors](https://github.com/LasithaAmarasinghe/Analog-Wall-Follow-Robot/blob/main/data%20sheets/GA12-N20%20Motor.pdf)\n* [L298N Motor Driver](https://github.com/LasithaAmarasinghe/Analog-Wall-Follow-Robot/blob/main/data%20sheets/L298%20Motor%20Driver.PDF)\n* Wheels\n* [Surface Mount Resistors](https://github.com/LasithaAmarasinghe/Analog-Wall-Follow-Robot/blob/main/Components/resistors.png)\n* [Surface Mount Capacitors](https://github.com/LasithaAmarasinghe/Analog-Wall-Follow-Robot/blob/main/Components/capacitors.png)\n* [Other Components](https://github.com/LasithaAmarasinghe/Analog-Wall-Follow-Robot/blob/main/Components/other%20components.png)\n\n## Software Specifications\n\n* Solid Works\n* Altium Designer\n* Multisim\n\n![Solidworks](https://img.shields.io/badge/Solid_Works_-red)\n![Altium](https://img.shields.io/badge/Altium_Designer_-%23A5915F?logo=altiumdesigner\u0026logoColor=white)\n![Multisim](https://img.shields.io/badge/Multisim_-%2357B685?logo=multisim\u0026logoColor=white)\n\n\n## Enclosure Design\n\n![297237961-194de710-68c9-488a-863e-5720f45de2e3](https://github.com/LasithaAmarasinghe/Analog-Wall-Follow-Robot/assets/106037441/2d6a547f-fbf7-422a-8413-5abb84247a53)\n\n## PCB Design\n\n![IMG-20231206-WA0012](https://github.com/LasithaAmarasinghe/Analog-Wall-Follow-Robot/assets/106037441/a627905f-60ce-4cc6-8d41-3c2be5a326dd)\n\n## PCB\n\n![20231201_162731](https://github.com/LasithaAmarasinghe/Analog-Wall-Follow-Robot/assets/106037441/6fb28673-3319-4657-9a23-ef2d5f0c3bc5)\n\n## Team Members\n\n![image](https://github.com/LasithaAmarasinghe/Analog-Wall-Follow-Robot/assets/106037441/5d1eefcf-3d5b-4ee2-8885-1eb820ad0053)\n![image](https://github.com/LasithaAmarasinghe/Analog-Wall-Follow-Robot/assets/106037441/5746e874-041f-421d-990f-f92470da315d)\n\n\n\n## License\n \n * This project is licensed under the MIT License. See the [LICENSE](MIT-LICENSE.txt) file for details.\n   \n## For More Information - [Project Report](https://github.com/LasithaAmarasinghe/Analog-Wall-Follow-Robot/blob/main/Project_Report.pdf)\n","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Flasithaamarasinghe%2Fanalog-wall-follow-robot","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Flasithaamarasinghe%2Fanalog-wall-follow-robot","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Flasithaamarasinghe%2Fanalog-wall-follow-robot/lists"}