High-Performance Flexible Cables for Industrial Robots

Industrial robots rely on flexible cables for power transmission and control signals. These cables must possess specific performance characteristics to withstand the demanding movements of robots, primarily within cable carrier systems (for external routing) and the robot arm itself (internal wiring). 

Like common 6-axis models) predominantly use these systems.

Robot Movement & Cable Stress

A 6-axis robot's complex movements (rotation, pitch, yaw, roll) subject attached cables to significant stresses:

Torsion: Twisting forces

Bending: Repeated flexing

Reciprocation: Continuous back-and-forth motion

Key Performance Requirements for Robot Cables:

Stable Power Transmission: Ensures uninterrupted robot operation.

Precise Signal Integrity: Critical for accurate reception and execution of control commands.

Long Mechanical Lifespan: Withstands constant bending, twisting, reciprocation, and friction to prevent conductor breakage, short circuits, or shield damage.

Robust Environmental Resistance: Must endure exposure to oils, coolants, water vapor, temperature extremes, and corrosive substances common in industrial settings.

Enhanced Design & Material Requirements (vs. Standard Flexible Cables):

Conductor Design (Critical for Lifespan & Breakage Prevention):

Use finer stranding (GB/T 3956-2008 Class 5 or 6 copper conductors).

Consider adding reinforcement filaments or using copper alloy conductors (accounting for potentially higher DC resistance).

Ensure uniform stress distribution during stranding/compounding.

Insulation Material Selection:

Balances dielectric properties, temperature rating, environmental resistance, flexibility, and abrasion resistance.

Optimize thickness for voltage rating while minimizing overall cable diameter.

For signal cables (e.g., encoder cables), use smooth, high-strength, low-friction insulation to prevent internal abrasion and failures.

Cabling Structure (Ensures Core Integrity & Flexibility):

Achieve a compact, round core bundle.

Utilize filler extrusion instead of a central core for better tensile load distribution.

Consider unit-stranding/sub-group designs for multi-core cables to allow individual core movement.

Carefully control lay lengths.

Shielding (For Signal Integrity & EMI/RFI Protection):

Employ fine copper or tinned copper braids.

For extreme flexibility, consider spiral shields made of tinned copper tape.

Select braid density and type considering flexibility needs.

Sheathing (Primary Environmental & Mechanical Protection):

Optimize thickness for protection while minimizing diameter.

Choose materials offering excellent abrasion resistance, mechanical strength, oil resistance, UV stability, and flexibility (e.g., specialized PUR, TPE).

Material selection must directly address the specific operating environment (oils, chemicals, temperature).