Three-Point Load Measurement for Driverless Transport Vehicles

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Driverless transport vehicles face challenges in accurately measuring load properties like mass and center of gravity, which affects stability and handling performance, often requiring worst-case scenarios that reduce handling capacity and increase safety risks due to uncertainties in load conditions.

Innovation Solution

The method involves a transport vehicle with a chassis and load-carrying platform connected via three force-measuring sensors, allowing for precise measurement of forces perpendicular and parallel to the road plane, enabling accurate calculation of load mass and center of gravity using electronic data processing, and adjusting the driving profile accordingly.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If force measurements are taken only in the vertical direction (z-direction) at three connection points, then the device complexity is reduced, but the measurement precision of load mass and center of gravity is insufficient

Engineering Contradiction:
Improvemeasurement system complexityVSAvoidload mass and center of gravity determination accuracy
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The patent extends the measurement from one dimension (vertical z-direction only) to three dimensions by adding force measurements in the longitudinal x-direction at connection points C1 and C2. This dimensional expansion enables accurate determination of both load mass and center of gravity position without requiring complex additional sensors, as the x-direction forces provide the necessary information about load distribution along the vehicle length.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Reliability

If the transport vehicle operates with worst-case scenario assumptions for safety, then the reliability is improved, but the handling performance and productivity are significantly reduced

Engineering Contradiction:
Improvesafety marginVSAvoidhandling capacity
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent implements a feedback mechanism where real-time force measurements from sensors at connection points are continuously processed to determine actual load mass and center of gravity position. This feedback enables the control system to adjust the driving profile dynamically based on actual loading conditions rather than relying on conservative worst-case assumptions, thereby maintaining safety while optimizing handling performance and productivity.

Inventive Principle:
Principle #23Feedback

3Measurement precision

If force measurements in the x-direction are measured directly at connection points, then the measurement precision is improved, but the device complexity increases

Engineering Contradiction:
Improvelongitudinal force measurement accuracyVSAvoidsensor system complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent makes the force sensors at connection points C1 and C2 multi-functional by designing them to measure both vertical (z-direction) and longitudinal (x-direction) forces simultaneously. This universal sensor design eliminates the need for separate measurement systems, achieving high measurement precision for both force components while avoiding the device complexity that would result from using multiple dedicated sensors.

Inventive Principle:
Principle #6Universality (Multi-functionality)

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

This approach optimizes handling performance and safety by ensuring the transport vehicle can handle loads within safe limits, reducing the risk of tipping and improving overall operational efficiency while providing accurate data for maintenance and load monitoring.

Implementation Method 1

force measurements are carried out by means of sensors at the connection points, wherein at least the forces perpendicular to the road surface (in the z-direction) are measured at all three connection points and the forces longitudinal to the direction of travel (in the x-direction) are determined

Methodology Applied
Scientific EffectForce measurement: Force

Data Source

PatentEP3995792B1Transport vehicle and method for determining load in a transport vehicle
Publication Date: 2023.12.20 STILL GMBH
  • EP3995792B1 patent drawingFigure 1
  • EP3995792B1 patent drawingFigure 2
  • EP3995792B1 patent drawingFigure 3

AI summary

The invention relates to a method for load measurement in a transport vehicle (1), in particular a driverless vehicle designed as a flat platform truck, for the horizontal transport of a load (A), wherein the transport vehicle (1) has a chassis (4) for driving on a road surface (FB) and a load receiving platform (5) for receiving the load (A), in particular arranged on a load carrier (C), wherein the chassis (4) is arranged in a vertical direction below the load receiving platform (5), and wherein the load receiving platform (5) is supported on the chassis (4) via three connection points.It is proposed that force measurements be carried out at the connection points using sensors (K1, K2), wherein at least the forces perpendicular to the road surface (FB) (in the z-direction) are measured at all three connection points, and the forces longitudinal to the direction of travel (in the x-direction) are determined during acceleration of the transport vehicle (1) in the direction of travel, and the mass and center of gravity of the load (A) are calculated from these measurements in an electronic data processing device. Furthermore, the invention relates to a transport vehicle (1) for carrying out the method.