Pulley Force-Amplifier Drive for Low-Backlash Robotic Power Transmission

Solution Overview

Problem

Existing power transmission drives are not well suited for robotic applications due to their bulkiness, heaviness, low precision, and high backlash, which limits their effectiveness in robotic systems.

Innovation Solution

A power transmission drive system utilizing a force amplifier with a first and second pulley set, each comprising fixed and floating pulleys, coupled by force amplification fibers, allowing independent actuation and reducing backlash, which amplifies force and increases power output.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Power

If traditional power transmission drives (helical gear, planetary gear, belt drive, chain drive) are used, then power transmission is achieved, but the system becomes bulky, heavy, and exhibits high backlash

Engineering Contradiction:

Improvepower transmissionVSAvoidsystem weight

Core Design Contradiction:

PowerVSWeight of moving object

Solution Approach 1:

The patent replaces traditional mechanical power transmission components (gears, belts, chains) with a tendon-driven robotic hand system that uses flexible cables and pulleys to transmit force from motors to fingers, eliminating bulky mechanical transmissions while maintaining power transmission capability

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent employs flexible cables (tendons) instead of rigid mechanical components to transmit force through the robotic hand structure, allowing for a lighter, more compact design while maintaining effective power transmission to the fingers

Inventive Principle:

Principle #30Flexible shells and thin films

2Power

If traditional power transmission drives are used, then power transmission is achieved, but the system exhibits high backlash and low precision

Engineering Contradiction:

Improvepower transmissionVSAvoidpositioning precision

Core Design Contradiction:

PowerVSMeasurement precision

Solution Approach 1:

The patent replaces traditional mechanical power transmission components (gears, belts, chains) with a tendon-driven robotic hand system that uses flexible cables and pulleys to transmit force from motors to fingers, eliminating bulky mechanical transmissions while maintaining power transmission capability

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent incorporates sensors and control systems that provide feedback on finger position and force, enabling precise control and compensation for any backlash or elasticity in the tendon-driven mechanism, thereby achieving high positioning precision

Inventive Principle:

Principle #23Feedback

3Power

If traditional power transmission drives are used, then power transmission is achieved, but the system becomes bulky

Engineering Contradiction:

Improvepower transmissionVSAvoidsystem volume

Core Design Contradiction:

PowerVSVolume of moving object

Solution Approach 1:

The patent replaces traditional mechanical power transmission components (gears, belts, chains) with a tendon-driven robotic hand system that uses flexible cables and pulleys to transmit force from motors to fingers, eliminating bulky mechanical transmissions while maintaining power transmission capability

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent integrates motors and pulleys within the compact structure of the robotic hand, nesting components within each other to minimize overall system volume while maintaining full power transmission functionality

Inventive Principle:

Principle #7Nested doll (Nesting)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The system provides high torque or speed output with minimal inertia and backlash, making it suitable for robotic applications by increasing power transmission efficiency and precision.

Implementation Method 1

a first force amplification fiber in tension that couples (e.g., in contact with and wraps at least partially around) the at least one fixed pulley to the at least one floating pulley of the first pulley set

Methodology Applied

Scientific EffectMechanical Advantage: Mechanical Advantage

Implementation Method 2

a first force amplification fiber in tension that couples (e.g., in contact with and wraps at least partially around) the at least one fixed pulley to the at least one floating pulley of the first pulley set

Methodology Applied

Scientific EffectTension: Tension

Data Source

PatentUS11339856B2Power transmission drive for robotic applications

Publication Date: 2022.05.24 ELEV8 DESIGN INC

AI summary

A power transmission drive includes a force amplifier configured to increase power output of at least one motor. The force amplifier includes a first pulley set and a second pulley set, each pulley set including at least one floating pulley and at least one fixed pulley. The first pulley set and the second pulley set are coupled to one or more motors by a corresponding force amplification fiber in tension. Actuation of the one or more motors actuate the first pulley set and the second pulley set. The first pulley set and the second pulley set transmit the force applied by the one or more motors to an output component.