Robotic Arm Design in India: From Kinematics to Manufactured Hardware, explained simply.
Custom robotic arm programs in India are increasingly viable — local CNC and sheet metal vendors, capable Indian motor manufacturers, and a maturing software ecosystem make ground-up arm builds practical at 30-50% of imported-arm pricing.
Core idea
What this blog covers
Indian teams that need a robotic arm for a specific application — pick-and-place, palletizing, machine tending — often face a buy-vs-build choice. Off-the-shelf arms (UR, Doosan, AUBO) are excellent but cost ₹8-25 lakh each. Custom arm programs can land at 40-60% of that cost for application-specific designs, but only with vendors who can handle mechanical, electrical, and software as one program.
Main discussion
Kinematic configuration — 6-DOF, SCARA, or Cartesian?
6-DOF anthropomorphic arms (the UR / Doosan style) cover the most application range — full 3D positioning with orientation control. SCARA (4-DOF, planar) is cheaper and faster for pick-and-place onto flat surfaces. Cartesian / gantry arms are stiffer and good for high-precision assembly but inflexible. We default to 6-DOF for general-purpose; SCARA when the application is clearly planar; Cartesian only for specific high-stiffness needs.
Joint design and gearbox selection
Each joint needs a motor + gearbox + encoder + bearing. For most custom Indian arms we specify cycloidal or harmonic drive gearboxes (now available from Sumitomo, Newall, and Chinese alternatives at reasonable cost), brushless servo motors with high-resolution encoders, and angular contact bearings. Joint torque budgeting matters — undersize and the arm sags under payload; oversize and you pay in cost and weight. Computed via worst-case payload at full reach plus dynamic loads.
Mechanical structure and stiffness
Aluminium structural members are the practical default — strength-to-weight ratio works for most payloads. Steel where stiffness matters specifically (typically the base segment). Hollow tubular members reduce weight at small stiffness cost. We use FEA (in-house) to verify stiffness under worst-case dynamic loads before fabrication — a stiffness study takes a few hours and prevents redesigns.
Software — MoveIt 2 + custom grasp planning
MoveIt 2 handles motion planning, collision checking, and basic grasp planning out of the box. For application-specific work — bin picking, machine tending, custom gripper coordination — we layer custom planners on top. Always build the simulation environment first (Gazebo or Isaac Sim) so software development and hardware development can run in parallel.
Manufacturing through Indian vendors
CNC machining for joint housings and structural members — multiple capable Indian vendors quoting competitively. Sheet metal for covers and shrouds — local Surat / Mumbai / Bangalore vendors. Custom PCB design and assembly — straightforward through Indian PCBA houses. Cycloidal / harmonic gearboxes — imported but landed cost manageable. Total bill of materials for a 6-DOF arm with 5 kg payload: typically ₹3-7 lakh, with software and engineering time on top.
Working with Yantrix on robotic arm design
We've delivered custom 6-DOF arms for teleoperation, pick-and-place, and machine-tending applications. Programs include mechanical design, gearbox / motor selection, embedded electronics, MoveIt configuration, and on-site commissioning. Send us your application and payload / reach requirements and we'll come back with a phased quote within a business day.
Key takeaways
What readers should remember
- 6-DOF is the practical default; 4-DOF SCARA is cheaper for planar applications.
- Cycloidal and harmonic drive gearboxes are now available from Indian and Chinese vendors at reasonable cost.
- Plan for repeatability targets in the spec — ±0.1 mm is achievable on custom arms with good gearboxes; ±0.05 mm requires significant cost.
- MoveIt 2 with custom URDF and grasp planning is the production software default.
Have a machine to build? Let's scope it together.
Tell us about your project. We'll respond within 1-2 business days with a preliminary scope and timeline — no boilerplate, no up-sell.