AGV Towing Path Reservation Using Dynamic Wagon Position Tracking

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing automated guided vehicle (AGV) systems face challenges in creating accurate traffic rules for towing vehicles pulling wagons, especially on curved paths, as the shape of the train varies, leading to unnecessary path reservations and increased manual labor.

Innovation Solution

The method calculates the current position of the wagon based on historical positions of the towing vehicle, allowing for more accurate traffic rule creation with reduced labor, by assigning reserved states to path portions and adjusting for safety margins based on the number of wagons and their size, thereby preventing collisions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a large static symbol covering both the AGV and wagon(s) is used for traffic rules, then collision avoidance is achieved on straight paths, but unnecessary path portions are reserved and blocked on curved paths

Engineering Contradiction:
Improvecollision avoidanceVSAvoidpath utilization
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent applies dynamics by making the symbol shape adaptive rather than static. The control unit dynamically adjusts the symbol geometry based on the train configuration (number of wagons, their lengths) and path curvature. This allows the reserved path portions to accurately match the actual space needed, preventing unnecessary reservations on curved paths while maintaining collision avoidance.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent changes geometric parameters of the symbol (shape, size, orientation) based on varying conditions such as the number of wagons, wagon lengths, and path curvature radius. By adjusting these parameters dynamically, the system optimizes path reservations to match actual spatial requirements, resolving the contradiction between safety and path utilization.

Inventive Principle:
Principle #35Parameter changes

2Reliability

If a large triangular symbol is used to cover all path portions that must be reserved, then every necessary path portion is reserved, but a lot of unnecessary reservations are created leading to very restricting traffic rules

Engineering Contradiction:
Improvepath portion reservation accuracyVSAvoidtraffic rule complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies local quality by creating different symbol shapes for different path sections. Instead of using a uniform large triangular symbol, the control unit calculates and applies locally optimized symbol geometries that match the specific curvature and spatial requirements of each path section. This reduces unnecessary reservations while maintaining necessary safety margins.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The system dynamically adjusts symbol parameters based on local path conditions (curvature radius, wagon configuration). This dynamic adaptation allows the traffic rules to be less restrictive by only reserving path portions that are actually necessary, rather than applying a conservative fixed geometry that over-reserves space.

Inventive Principle:
Principle #15Dynamics

3Measurement precision

If all blocking rules for curved path portions are calculated manually, then accurate traffic rules are created, but a lot of labour is required and restrictions in traffic increase

Engineering Contradiction:
Improvetraffic rule accuracyVSAvoidmanual work time
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The patent implements self-service by enabling the control unit to automatically calculate and update symbol shapes and path reservations based on real-time train configuration data. The system self-adjusts the traffic rules without manual intervention, computing the appropriate symbol geometry based on the number of wagons, their lengths, and the path curvature, thereby eliminating manual labor while maintaining accuracy.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The system uses feedback from the train configuration (number of wagons, their lengths, positions) to dynamically adjust the symbol shape and path reservations. This closed-loop approach ensures accurate traffic rules are automatically generated based on actual operational conditions, replacing manual calculation with automated real-time computation.

Inventive Principle:
Principle #23Feedback

4Device complexity

If the train shape is considered fixed for traffic rules, then rule creation is simpler, but the shape varies on curved paths causing inaccurate reservations

Engineering Contradiction:
Improverule creation complexityVSAvoidwagon position accuracy
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The patent resolves this contradiction by making the symbol representation dynamic rather than fixed. The control unit continuously updates the symbol shape and position based on the train's actual configuration and its position on the path, particularly accounting for curvature effects. This dynamic approach maintains measurement precision while keeping rule creation manageable through automated calculation.

Inventive Principle:
Principle #15Dynamics

Data Source

PatentEP3364263B1Method for controlling the travel path of automated guided vehicles
Publication Date: 2021.05.26 KOLLMORGEN AUTOMATION AB
  • EP3364263B1 patent drawingFigure 1a~1e
  • EP3364263B1 patent drawingFigure 2a~2b
  • EP3364263B1 patent drawingFigure 2c~2d

AI summary

The present invention relates to a method and a system for controlling the travel path of automated guided vehicles in a system where at least one automated guided vehicle is in the form of a towing vehicle pulling at least a first wagon. A path for the towing vehicle to travel along is determined, as well as a first position of the towing vehicle. Data identifying the first position is stored in a data storage unit and a reserved state is assigned to a path portion based on the stored data. A second vehicle is prohibited from entering the path portion while in the reserved state, to prevent collision. The towing vehicle is moved from the first position, along the path, to a second position, and the reserved state of the path portion is cancelled once the first wagon has passed the path portion.