Design of Robot Elements syllabus

Introduction to Loads: Static, Fluctuating (repeated, reversed, and random), and impact loads, Load cycles in robot operation. Static Load Design: Factor of safety (FoS), Design for static strength, Stress Concentration: Causes, stress concentration factors, Failure theories applications. Fatigue Load Design: Cyclic stress, Endurance limit, S-N curve, Fatigue failure stages (crack initiation, propagation), Fatigue strength modifying factors, Fatigue failure theories: Soderberg, Goodman, Gerber criteria, Combined mean and alternating stress, Design for infinite life.

Design of Shaft: Introduction and Robot specific requirements, Shaft design on the strength basis, Torsional rigidity basis and lateral rigidity basis, Hollow shaft design, Design of shaft as per ASME code, Shaft connections for robots. Design of Bearings: Introduction and Robot specific requirements, Classification of bearings for robotics, Bearing selection criteria: load, speed, temperature, and alignment, Static and dynamic load carrying capacities, Lubrication, maintenance, and failure prevention.

Introduction & Terminology: Introduction to Gears in Robotics, Gear Terminology & Geometry. Gear Design: Beam strength of gear tooth, Lewis form factor, Allowable stress, Design for safe bending stress. Numerical on finding module, Harmonic drive (concept only). Power Screws Design: Types of screw threads, Lead screw vs. ball screw, Torque analysis with square & trapezoidal threads, Efficiency, Self-locking condition, Stresses in power screws, Torque to raise/lower load, Robot applications (prismatic joints, SCARA Z-axis). Timing Belts: Timing belts in robots (GT2, GT3, HTD), Geometrical relations (pitch length, center distance), Analysis of belt tensions, Selection of timing belts (pitch, width, material).

Introduction & Types: Introduction to end effectors, Types: grippers vs. tools, Considerations for gripper selection: part geometry, environment, cycle time, grip type. Design of Mechanical Grippers: Force analysis, Mechanism: Parallel jaw gripper (rack & pinion, double pivoting, toggle linkage), Jaw stroke, Actuation force (pneumatic or electric), Material for jaws (hardened steel, aluminum with rubber pad). Other Types of Grippers: Vacuum grippers, Magnetic grippers, Soft/ compliant grippers. Tools as End Effector & Robot Interface: Tool types with applications, Mechanical interface: ISO 9409-1, Physical support of the end effector.

Fasteners for Robots: Introduction to Threaded Joints, Bolt types (hex head, socket cap), Bolt grades (8.8, 10.9, and 12.9), Preload, and Torque tightening formula. Locking devices: Need for locking in vibrating robots, Spring washer, Nord-Lock wedge washer, Loctite thread locker (blue 242, red 271), Nyloc nut, Safety wire, and Selection guide. Springs in robots: Need for springs (gravity compensation, compliance, and return mechanism), Compression spring, Torsion spring, Spring rate selection for gravity counterbalance.