Search this site

Try a part name, a rupee figure, or the fault you are chasing.

Free project pack

What are you building today?

Robotics projects that work on demo day, parts lists in rupees, and fixes for the error on your screen right now.

Final-year projects Fix an upload error Servo torque Report format

278 guides 92 part guides 18 build sheets ₹ costs in rupees, labelled as illustrations

Written, checked and maintained by Jignesh Panchal, published by Jaadu Digital. How we work

Arm lab · real kinematics
Side view · 12 cm and 10 cm links

Masses assumed: upper link 45 g, elbow servo 55 g, forearm 35 g, gripper 60 g. Torque is static holding torque in kg·cm. Size your own servo

Costs in ₹, labelled honestly

Price ranges are illustrations from Indian listings, never presented as quotes or surveys.

The maths is on the page

Worked examples show inputs, units and equations, so you can reproduce the result.

Specs from the maker

Product numbers come from manufacturer documentation, not from search snippets.

Not “tested” unless it was

A bench-tested claim needs dated measurements. Without them, a guide is educational.

Checked before it goes live

Found a mistake? Send it with evidence; safety and calculation errors go first.

Commissions disclosed

Affiliate links are marked, and a commission never stands in for testing.

Read the full editorial standard · Affiliate disclosure · Report a mistake

Error Doctor · runs in your browser

Stuck? Paste the error.

Copy the red text from the Arduino IDE, ESP-IDF or your ROS terminal. You get the likely causes, most common first, and the fix in order.

The Error Doctor needs JavaScript. You can still search the tutorials for your error.

Quick check

A servo arm holds 300 g at 20 cm. What torque does it need, before any safety margin?

Pick one. The working shows after you choose.

Why the doctor is honest

It says “partial match” when it isn’t sure

No match? It writes a question you can paste into your own AI assistant, with your error filled in and the gaps marked. Nothing you paste leaves this page.

Two front doors

Start where you are

Students and makers

Build →

Projects by budget and branch, parts that work together, and fixes for the error that stopped you at 2 a.m.

Factories and plant engineers

Automate →

Robot cells and cobots in an Indian context, what to ask before you call an integrator, and the roles that run them.

Workbench

Tools you’ll keep open in a tab

Each one shows its formula. “Copy to report” adds the working and the source line for you.

All calculators →

Calculator · servo torque

Runs in your browser

Which servo can hold it?

Supply
9.6kg·cm
0.94 N·m with margin · 6.4 kg·cm without

τ = (load × L + arm weight × L/2) × SF = (300 g × 20 cm + 40 g × 10.0 cm) × 1.5

Stall ratings are typical published figures. Never run a servo near stall for long; check the datasheet for yours.

Servo torque calculator

The full version, with gear trains and units explained.

Battery run time

How long the pack lasts at the current you actually draw.

Project cost

Add up the parts list, spares and shipping before you order.

Build checker

Logic levels, power and run time for a parts list.

My Build · checked before you buy

Will these parts work together?

Tick what you plan to use. The checker looks for logic-level clashes, power problems and missing parts, then estimates current draw, run time and cost.

The build checker needs JavaScript. The battery run time calculator covers the power side.

    Current figures are typical values for these modules. Costs are illustrative Indian retail ranges, not quotes; check the seller’s price before you buy.

    The library

    Start with a build that fits your bench.

    Each project page opens with the parts total, the bench time and the skill level — before the steps. If it does not fit your budget, you know in ten seconds.

    Browse all projects

    Free: the final-year project pack

    A shortlist with BOMs, a report outline that matches the usual chapter scheme, a costing sheet and 40 viva questions. Built for the February–April submission season.

    Get the free pack

    The Build Note

    One short email when something is worth your bench time.

    A new build sheet, a part price that moved, or a mistake worth avoiding. No daily drip, no recycled news.

    One short email when a build or a price is worth your time. Unsubscribe in one click.

    Straight answers

    What you should know before you start.

    Are these builds tested?

    Every guide is checked against component datasheets and known-good reference designs, and the code is compiled before publishing. A build marked Bench-tested has been assembled and measured on a real bench; that badge appears only when it is true. Each page shows the date it was last reviewed.

    What do the costs include?

    Parts only, in Indian rupees, at a reliable listing we found when the page was last reviewed. Shipping, tools and consumables such as solder, wire and tape are called out separately where they change the total.

    Can I submit one of these as my final-year project?

    Yes, but check your university's rules first. The final-year route covers scope, report structure, costing and viva questions. It cannot guarantee approval, originality or marks.

    Do you sell kits?

    No. We publish the parts list and link to stores we would order from ourselves. Some links are affiliate links, which may earn us a commission at no extra cost to you.

    I have never built a circuit. Where do I start?

    Start with the four-week beginner route: pick a board, build a line follower, then add obstacle detection. You need no prior electronics, but you do need a multimeter, a breadboard and patience.