Motor Grader 3D Grade Control Without Blade Masts

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing construction machines face limitations in grade control systems, particularly those with masts attached to the blade, which restrict blade placement range, increase theft risk, and cause potential damage due to mast interaction with the cab during operations.

Innovation Solution

A machine control system for construction machines that integrates rotation sensors (IMU) and positioning sensors (GNSS or UTS) to establish blade positions within a world space, eliminating the need for mast-based systems by strategically mounting these sensors to detect and calculate blade positions accurately.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If mast-based grade control systems are attached to the blade, then grade control functionality is provided, but blade placement range is restricted and theft risk increases

Engineering Contradiction:
Improveblade placement rangeVSAvoidtheft risk
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The patent removes the physical masts from the blade and extracts the grade control functionality to a separate control system with sensors mounted on the machine body. This extraction eliminates the theft risk and placement range restrictions while maintaining grade control capabilities through alternative sensing methods.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent introduces an intermediary control system that uses body angle sensors, drawbar angle sensors, and positioning sensors to indirectly determine blade position without physical masts. This intermediary system mediates between the machine's movement and the grading function, eliminating the need for blade-mounted hardware.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If mast-based grade control systems are attached to the blade, then grade control functionality is provided, but potential damage occurs due to mast interaction with the cab

Engineering Contradiction:
Improvedamage riskVSAvoidgrade control functionality
Core Design Contradiction:
ReliabilityVSAdaptability or versatility

Solution Approach 1:

The patent extracts the grade control sensing functionality from the blade area where masts would interact with the cab, and relocates it to the machine body. This separation eliminates the damage risk from mast-cab interaction while preserving complete grade control functionality through alternative sensing approaches.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent replaces the mechanical mast system with an electronic sensing system comprising body angle sensors, drawbar angle sensors, and positioning sensors. This substitution eliminates the physical components that could interact with the cab while maintaining the grade control function through computational methods.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

3Measurement precision

If mast-based systems are used for grade control, then blade position control is achieved, but device complexity and potential damage increase

Engineering Contradiction:
Improveblade position controlVSAvoidsystem complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent replaces the complex mechanical mast system with an electronic sensing and computational system. The body angle sensor, drawbar angle sensor, and positioning sensor work together with a control system to calculate blade position, achieving precise control while reducing mechanical complexity and elimination of physical masts.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Data Source

PatentEP3908702B1Motor grader 3D grade control
Publication Date: 2026.03.04 CATERPILLAR TRIMBLE CONTROL TECHNOLOGIES LLC
  • EP3908702B1 patent drawingFigure 1
  • EP3908702B1 patent drawingFigure 2A
  • EP3908702B1 patent drawingFigure 2B

AI summary

Systems and methods for providing grade control on a motor grader without the use of masts attached to the blade. Embodiments include a body angle sensor configured to detect movement of a construction machine's body, a front positioning sensor configured to detect a geospatial position of the construction machine's body within a world space, a drawbar angle sensor configured to detect movement of the construction machine's drawbar, and a blade angle sensor configured to detect movement of the construction machine's blade. Two positions on the blade may be calculated first within a machine space and subsequently within the world space. Movement of at least one articulating connection may be caused based on the blade positions within the world space.