Materials Selection

Material selection shapes a robot’s performance, weight, cost, and durability. Choosing the right material balances mechanical requirements with budget, manufacturing methods, and operating environment.

Key Factors in Material Selection

• Mechanical properties (strength, stiffness, wear resistance)

• Weight and strength-to-weight ratio

• Corrosion and environmental resistance

• Manufacturability (machinability, joinability, 3D printing compatibility)

• Cost and availability

• Application-specific needs (e.g., electrical insulation, biocompatibility)

Common Materials and Their Pros & Cons

Material	Pros	Cons
Steel	High tensile strength and excellent wear resistance2	Heavy compared to alternatives; may require coatings to prevent rust2
Aluminum	Lightweight with good strength, corrosion-resistant, easy to machine2	Lower ultimate strength than steel; may need reinforcement under heavy loads2
Carbon Fiber	Exceptional strength-to-weight ratio and stiffness2	Expensive; brittle under concentrated stress; complex fabrication2
Titanium	High strength-to-weight, corrosion-resistant, biocompatible2	Very costly; difficult to machine; limited for budget projects2
ABS Plastic	Good strength-to-weight, impact-resistant, cost-effective4	Lower heat resistance and durability; unsuitable for heavy loads4
Composites	Customizable properties, lightweight, high fatigue resistance4	High material and processing cost; complex repair and recycling4
Elastomers	Flexible, shock-absorbing, safe for human interaction2	Poor structural rigidity; degrades over time in harsh environments2

Application Guidelines

• Structural Frames: Favor aluminum or steel for load-bearing members; use composites where weight savings justify cost.

• Precision or High-Speed Mechanisms: Carbon fiber or specialized alloys deliver stiffness and low inertia.

• Corrosive or High-Temperature Settings: Stainless steel, nickel-based alloys, or ceramics resist wear and oxidation.

• Rapid Prototyping: 3D-printable plastics (PLA, ABS) enable quick iteration before committing to final materials4.
• Soft Robotics and Grips: Elastomers (silicone, polyurethane) provide compliance and gentle object handling2.

Selecting the optimal material mix requires matching each component’s function with material attributes and project constraints. A well-balanced choice boosts robot reliability, efficiency, and longevity.