Mechanical · Machine and manufacturing · Final year project
PLC Based Automatic Sorting System using Image Processing
An automatic sorting line that uses a Raspberry Pi camera to measure each object's shape, size or colour, and a PLC to push it into the right bin.
What is the PLC Based Automatic Sorting System using Image Processing project?
An automatic sorting line that uses a Raspberry Pi camera to measure each object's shape, size or colour, and a PLC to push it into the right bin.
Key facts
- Branch
- Mechanical & Automobile Engineering; also suits Mechatronics
- Type
- Final year project · Advanced
- Suitable for
- Diploma capstone and B.E / B.Tech final year
- Build time
- 6 to 8 weeks
- Estimated component cost
- ₹21,000 – ₹30,800
- Guidance from
- ₹9,999 (Hardware / IoT Final Year)
How the PLC Based Automatic Sorting System using Image Processing works
- The mild steel frame and fabrication forms the base that carries every other part, so it is designed first from the load and size of the machine.
- The DC geared motor provides the driving motion.
- The Pneumatic cylinder converts compressed air into linear push-pull motion.
- Motion is transmitted through camera module and DC geared motor, which set the speed, torque and direction at the working end.
- The Raspberry Pi 4 runs Linux and the main program, handles the camera, networking and heavier processing such as image recognition.
- The Compact PLC runs the ladder logic that sequences the machine's inputs and outputs, the way industry automates processes.
- The Camera module captures images or video for recognition and monitoring.
Block diagram
Power
DC geared motorSolenoid lockRelay moduleTransmission
DC geared motorWorking unit
Pneumatic cylinderStructure
Frame and mountsComponents list and cost
Typical prices from Indian online stores and electronics markets (Lamington Road, Budhwar Peth, SP Road). Buy from one store where you can to save on shipping.
| Component | Qty | What it does | Approx. cost |
|---|---|---|---|
| Raspberry Pi 4 (2 GB) | 1 | Runs Linux and the main program, handles the camera, networking and heavier processing such as image recognition. | ₹4,800 |
| Compact PLC (e.g. Delta DVP / Siemens LOGO!) | 1 | Runs the ladder logic that sequences the machine's inputs and outputs, the way industry automates processes. | ₹9,500 |
| Camera module | 2 | Captures images or video for recognition and monitoring. | ₹1,300 |
| DC geared motor | 1 | Provides the driving motion. | ₹250 |
| Solenoid lock (12 V) | 1 | Locks or unlocks the door when energised. | ₹450 |
| Relay module | 1 | Switches mains or high-current loads such as lamps, pumps and fans from a low-voltage signal. | ₹70 |
| Pneumatic cylinder | 1 | Converts compressed air into linear push-pull motion. | ₹1,800 |
| Mild steel frame and fabrication | 1 | Forms the main structure that holds all parts. | ₹2,500 |
| Welding, cutting and machining labour | 1 | Needed for this type of build. | ₹2,200 |
| Aluminium conveyor | 1 | Part from the design specification | ₹400* |
| Buttons | 1 | Part from the design specification | ₹400* |
| Paint, finishing and workshop consumables | 1 | Project overhead | ₹600 |
| Transport of material | 1 | Project overhead | ₹400 |
| Estimated total | Varies with brand, quality and city | ₹21,000 – ₹30,800 |
Prices are estimates for budgeting; items marked * depend on the exact size or model chosen. We confirm the bill of materials when your design is frozen, and components are charged at actual cost with bills.
How much does this project cost?
| Option | What you get | Cost |
|---|---|---|
| Components only | You buy the parts and build it yourself | ₹21,000 – ₹30,800 |
| Hardware / IoT Final Year | Working model or guided build, Circuit diagram and bill of materials, Firmware / code with explanation | from ₹9,999 + components |
| Capstone Project (CPE) | Working project or model, Black book in MSBTE format, Step-by-step explanation | ₹9,999 + components |
| Diploma ITR | 100% working source code, Project report PDF, PPT | ₹1,999 + components |
No GST and no hidden charges. Use the cost calculator for a quote with your deadline and add-ons, or see all plans.
Download the project brief (PDF)
Summary, working, components and cost and viva questions on one branded PDF to show your guide or team. To get it developed, contact us on WhatsApp.
What you submit with this project
- Working model with circuit diagram and program code
- Project report or black book in your university's chapter order (block diagram, circuit, calculations, results)
- Presentation for the review and final viva
- Synopsis for topic approval, if your college asks for one
Mechanical viva questions on this project
What is the aim of the PLC Based Automatic Sorting System using Image Processing project?
An automatic sorting line that uses a Raspberry Pi camera to measure each object's shape, size or colour, and a PLC to push it into the right bin.
Explain the working of your project in short.
The mild steel frame and fabrication forms the base that carries every other part, so it is designed first from the load and size of the machine. The DC geared motor provides the driving motion. The Pneumatic cylinder converts compressed air into linear push-pull motion. Motion is transmitted through camera module and DC geared motor, which set the speed, torque and direction at the working end.
Why did you choose a Raspberry Pi instead of an Arduino?
The Raspberry Pi is a full computer with an operating system, so it can run Python, OpenCV and a web server. An Arduino is a microcontroller that is better for simple real-time control but cannot process images or run multiple programs.
Why is a PLC preferred over a microcontroller in industry?
A PLC is rugged, works on 24 V industrial signals, tolerates noise and heat, and is programmed in ladder logic that maintenance staff understand. It is also easy to modify on site.
How is the camera image processed?
Frames are captured and processed with OpenCV: converted to grayscale, filtered and passed to a detection or recognition model that labels faces, objects or number plates.
Why is a geared motor used?
The gearbox reduces speed and multiplies torque, so a small DC motor can move a vehicle or mechanism smoothly. Torque increases roughly by the gear ratio.
How does a solenoid lock work?
When current flows, the coil becomes an electromagnet and pulls the plunger in, releasing the latch. When current stops, the spring pushes the plunger back to lock.
Which material did you select for the main parts and why?
Mild steel (MS) is used for the frame because it is strong, cheap, easy to cut and weld and available everywhere. Shafts are made of EN8 or bright mild steel for strength, and parts that do not carry load can be aluminium or acrylic to reduce weight.
What factor of safety did you take in your design?
A factor of safety of 2 to 3 is taken for static parts and 3 to 5 for parts under shock or fatigue loading. Allowable stress = yield strength ÷ factor of safety, and each part is checked against it.
How did you estimate the cost of the project?
The cost is the sum of raw material, bought-out parts, machining or fabrication and overheads. Our estimate for this model is about ₹21,000 to ₹30,800, depending on size, material and the workshop rates in your city.
Which manufacturing processes were used?
Cutting and grinding of sections, arc or MIG welding of the frame, drilling for mounting holes, turning of the shafts and fitting of bearings and the drive, followed by assembly, alignment and painting.
Is your system open-loop or closed-loop?
Closed-loop: sensors measure the actual position, distance or condition and the controller corrects the actuators until the target is reached.
Related projects
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Want to build PLC Based Automatic Sorting System using Image Processing?
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