Hybrid Robot Neck Mechanism for 3D Pose Tracking

Solution Overview

Problem

Current neck mechanisms for robots, whether serial or parallel, face limitations such as restricted degrees of freedom, high inertia, low load capacity, and complex kinematic analysis, which hinder their effectiveness in simulating human-like movements and interactions, especially in healthcare settings where load and rigidity are critical.

Innovation Solution

A neck mechanism that combines elements of both serial and parallel structures using one servo and two linear actuators to achieve three degrees of freedom (pitch, roll, yaw) while maintaining simplicity and reducing costs, facilitating kinematic analysis and human-robot interaction through a perception control system.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a serial neck mechanism with multiple degrees of freedom is used, then the representation of neck movements is improved, but the inertia of transmission structures increases and load capacity decreases

Engineering Contradiction:

Improverepresentation of neck movementsVSAvoidload capacity

Core Design Contradiction:

Adaptability or versatilityVSForce

Solution Approach 1:

The neck mechanism is divided into multiple independent rotational joints (pitch joint, roll joint, yaw joint) that can move separately. Each joint is actuated by its own motor, allowing independent control of each degree of freedom. This segmentation enables complex neck movements while keeping each transmission structure relatively simple and lightweight, avoiding the high inertia problem of fully serial mechanisms.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The mechanism transitions from a purely serial structure to a hybrid structure by introducing parallel support legs connected to the base. These support legs provide structural stability and load-bearing capacity in the vertical dimension, while the rotational joints provide movement freedom in angular dimensions. This dimensional separation allows the mechanism to achieve both high load capacity and good movement representation.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

2Adaptability or versatility

If a parallel neck mechanism is used, then the representation of neck movements is improved, but the complexity of kinematic analysis increases

Engineering Contradiction:

Improverepresentation of neck movementsVSAvoidcomplexity of kinematic analysis

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The neck mechanism is divided into multiple independent rotational joints (pitch joint, roll joint, yaw joint) that can move separately. Each joint is actuated by its own motor, allowing independent control of each degree of freedom. This segmentation enables complex neck movements while keeping each transmission structure relatively simple and lightweight, avoiding the high inertia problem of fully serial mechanisms.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The mechanism transitions from a purely serial structure to a hybrid structure by introducing parallel support legs connected to the base. These support legs provide structural stability and load-bearing capacity in the vertical dimension, while the rotational joints provide movement freedom in angular dimensions. This dimensional separation allows the mechanism to achieve both high load capacity and good movement representation.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

3Device complexity

If a serial neck mechanism is used, then the structure is simple and cost is reduced, but the degrees of freedom are limited

Engineering Contradiction:

Improvestructure simplicityVSAvoiddegrees of freedom

Core Design Contradiction:

Device complexityVSAdaptability or versatility

Solution Approach 1:

The neck mechanism is divided into multiple independent rotational joints (pitch joint, roll joint, yaw joint) that can move separately. Each joint is actuated by its own motor, allowing independent control of each degree of freedom. This segmentation enables complex neck movements while keeping each transmission structure relatively simple and lightweight, avoiding the high inertia problem of fully serial mechanisms.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The mechanism transitions from a purely serial structure to a hybrid structure by introducing parallel support legs connected to the base. These support legs provide structural stability and load-bearing capacity in the vertical dimension, while the rotational joints provide movement freedom in angular dimensions. This dimensional separation allows the mechanism to achieve both high load capacity and good movement representation.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

Data Source

PatentUS11440198B2Control system and method for movement of neck mechanism for robot

Publication Date: 2022.09.13 UBTECH ROBOTICS CORP LTD

AI summary

A control system for a neck mechanism includes a perception system configured to track movement of an object, and a perception control system that controls a rotary motor to yaw a platform and controls a first linear actuator and a second linear actuator that is in parallel with the first linear actuator to pitch and roll the platform according to a target position of the platform. The perception system tracks movement of the object by estimating its position and pose in 3D space and the platform is moved according to a vision-based position and pose estimation result.