Mechanical · Automobile engineering · Final year project
Expandable Transforming Ebike 1 to 3 Seater
An electric bike whose seat slides out to carry up to three people. Seats on a slider convert it from a single-seater to a three-seater for urban family trips.
What is the Expandable Transforming Ebike 1 to 3 Seater project?
An electric bike whose seat slides out to carry up to three people. Seats on a slider convert it from a single-seater to a three-seater for urban family trips.
Key facts
- Branch
- Mechanical & Automobile Engineering; also suits Mechatronics
- Type
- Final year project · Intermediate
- Suitable for
- Diploma capstone and B.E / B.Tech final year
- Build time
- 4 to 6 weeks
- Estimated component cost
- ₹33,500 – ₹49,300
- Guidance from
- ₹9,999 (Hardware / IoT Final Year)
How the Expandable Transforming Ebike 1 to 3 Seater 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 parts are assembled, aligned and tested under load, and the readings are recorded for the results chapter.
Block diagram
Power
Rechargeable batteryStructure
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 |
|---|---|---|---|
| Rechargeable battery (12 V 1.3–7 Ah) | 1 | Stores energy and supplies power when mains is absent. | ₹650 |
| Mild steel frame and fabrication | 1 | Forms the main structure that holds all parts. | ₹2,500 |
| BLDC hub motor 250-350 W | 1 | Needed for this type of build. | ₹7,500 |
| Motor controller with throttle | 1 | Needed for this type of build. | ₹2,900 |
| Li-ion battery pack 36 V 10 Ah with BMS | 1 | Needed for this type of build. | ₹14,500 |
| Base frame / bicycle and fabrication | 1 | Needed for this type of build. | ₹6,500 |
| Brakes, cables and wiring | 1 | Needed for this type of build. | ₹1,400 |
| Welding, cutting and machining labour | 1 | Needed for this type of build. | ₹2,200 |
| Mounts, screws, nuts and small hardware | 1 | Enclosure, mounts and fasteners. | ₹300 |
| Paint, finishing and workshop consumables | 1 | Project overhead | ₹600 |
| Transport of material | 1 | Project overhead | ₹400 |
| Estimated total | Varies with brand, quality and city | ₹33,500 – ₹49,300 |
Prices are estimates for budgeting. 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 | ₹33,500 – ₹49,300 |
| 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 Expandable Transforming Ebike 1 to 3 Seater project?
An electric bike whose seat slides out to carry up to three people. Seats on a slider convert it from a single-seater to a three-seater for urban family trips.
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 parts are assembled, aligned and tested under load, and the readings are recorded for the results chapter.
How do you calculate battery backup time?
Backup time (hours) ≈ battery capacity (Ah) × voltage × 0.8 efficiency ÷ load power (W). For example, 12 V 7 Ah at 20 W gives about 3.3 hours.
Why is mild steel used for the frame?
It is cheap, strong, easy to cut and weld and widely available. A frame of 25 mm square pipe is enough for most student models.
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 ₹33,500 to ₹49,300, 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, followed by assembly, alignment and painting.
Is your system open-loop or closed-loop?
Mainly open-loop: the controller runs the actuators for a set time or number of steps. Adding a sensor for feedback would make it closed-loop and more accurate.
Related projects
Academic use: Project Buddyy offers mentoring, guidance and reference material for learning. You stay responsible for following your institution's academic integrity rules and for understanding everything you submit.
Want to build Expandable Transforming Ebike 1 to 3 Seater?
Send your college, deadline and team size. We confirm the scope, cost and what you will submit.