INDRBT / ENGINEERING

INDRBT / Reading room

Mechanical design tour

Digital engineering model. Payload and repeatability are design targets. All ordinary guide reading, figures and PDFs work here. Links marked Source file lead to the public engineering repository.

Adapted for browser reading from the project’s illustrated documentation. Numeric results and engineering scope are unchanged. Reproduction notes are optional; the robot and board viewers run from the navigation above.

On this page

Open the interactive robot online — no CAD application or GitHub access required.

Project home · CAD files · All 54 components · Detailed CAD method

Download the public CAD inspection packsSource file — STEP/STL exchange geometry, the native FreeCAD model, PCB STEP and the combined offline pack. The native-file guide explains millimetre units and opening/importing each format. The published GitHub Pages showcase includes the browser viewers and download controls.

INDRBT connects a six-axis arm to an interchangeable parallel gripper. The model has 54 solid components, six saved poses and 90 mm of clear jaw opening. These images come from the project's CAD geometry; the same part meshes drive the offline interactive viewer.

INDRBT home assembly, showing the fixed base, two arm links, wrist and parallel gripper

Choose how to explore

You want to inspect View directly on GitHub Download and open locally
The complete robot Assembly image · six poses FreeCAD assemblySource file · home STEPSource file
The gripping mechanism Gripper close-up · dimensioned layout Gripper body STEPSource file · part catalog
Dimensions and interfaces Base and flange · link sections Three-page drawing PDF
Joint motion or one isolated part Six-pose sheet Interactive viewer: pose selector, joint controls and component selector

Use the public robot viewer for online inspection, joint controls and playback. For an optional offline copy, download or clone the complete project, then use OPEN_3D_VIEWER.cmdSource file on Windows. OPEN_FREECAD_MODEL.cmdSource file opens the native model for optional CAD inspection or editing. On other systems, open the downloaded viewer HTML in a browser or the native model in FreeCAD. GitHub displays the repository HTML source rather than running it.

Follow the mechanical chain

The fixed mounting plate and hollow riser support a rotating turret. Shoulder and elbow joints position the two hollow arm links; three wrist rotations orient the tool. The joint-axis sequence is Z–Y–Y–X–Y–X. The configured upper-arm and forearm centre spacings are 320 and 280 mm.

Base and tool interfaces Arm structure
Dimensioned base mounting plate and interchangeable tool flange Upper-arm and forearm sections, spacing and access openings
The Ø220 base plate has eight mounting holes with 7 mm counterbores. A hollow route passes through the base and joint envelopes. Hollow link sections, external elbow cheeks and removable service covers provide a visible structural layout and access route. The covers are not assumed to restore the cut sections' stiffness.

The wrist finishes at a six-hole tool flange. Its Ø30 × 4 mm locating spigot enters the adapter's Ø30.2 bore; the Ø60 adapter retains 4.25 mm of material outside each bolt hole. Matching bolt passages continue through the gripper rear wall. The rear cable opening reaches the gripper pocket. These details connect the tool to the arm geometrically; final fasteners, tolerance stacks and cable bends remain concept work.

How the gripper works

Actual CAD close-up of the two guides, screw envelope, carriages, fingers and contact pads

An opposite-hand screw concept moves two carriages equally in opposite directions along two steel guide rods. Each jaw travels 45 mm, producing 0–90 mm clearance between the contact pads. The fingers extend along tool X; opening and closing occurs along tool ±Y. The configured screw lead is 4 mm per revolution.

Dimensioned gripper layout with guide rods, nut bosses, fingers and service hatch

The carriages include connected nut bosses and finger support tabs. The two finger fastener holes align with the tabs, replaceable pads define the contact surfaces, and a top hatch provides access without intersecting the adapter. The modeled screw and smooth nut bores locate the drive concept; they do not represent engaged threads, preload or simulated contact force. The mechanical calculations explain the separate grip-force and screw-torque model.

Compare six configurations

The six CAD configurations: home, extended, folded, vertical, pick and place

Home Extended Folded Vertical Pick Place
STEPSource file STEPSource file STEPSource file STEPSource file STEPSource file STEPSource file

Individual STEP/STL parts use their local assembly-group frames and millimetres. Opening every part at a common origin will not assemble the robot. Use a complete pose file, the FreeCAD home assembly or the viewer; the kinematics guide defines the transforms.

Where the design lives

robot.yaml supplies the SI dimensions. Build123d geometrySource file constructs the solids, and assembly.pySource file places them using the robot's joint frames. This Python source is the reproducible parametric design. The FreeCAD file contains the exported home-pose solids with descriptive labels and material/group metadata; it is an inspection assembly rather than a sketch-based feature tree.

The CAD audit checks exported solids, native visibility, interfaces, five jaw openings and source bindings. Named-pose and sampled-task clearance evidence accompanies it. These checks support the digital model; they do not establish physical payload, repeatability or production readiness. For reproduction and the exact validation scope, continue to the CAD method and source CAD guide.