Automated Storage Vehicle UWB Positioning for Collision-Free Movement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing automated storage and retrieval systems face challenges in accurately controlling the movement of container handling vehicles, leading to inefficiencies and potential collisions due to insufficient positioning information and delayed command relay.
Innovation Solution
Implementing a positioning system with UWB nodes and a control system that uses time of flight (TOF) or time difference of arrival (TDOA) measurements to determine the precise positions of container handling vehicles, allowing them to form a 'train' of vehicles moving in tandem at a predetermined separation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional positioning systems are used to track container handling vehicles, then system complexity is reduced, but positioning accuracy and real-time tracking capability deteriorate leading to potential collisions and inefficiencies
Solution Approach 1:
A positioning system comprising multiple positioning nodes (UWB transceivers) distributed throughout the storage facility acts as an intermediary between the vehicles and the control system. These nodes continuously measure signal characteristics (TOF/TDOA) to determine vehicle positions, providing real-time data without requiring complex onboard sensors on each vehicle. The positioning nodes form a distributed measurement network that accurately tracks vehicle locations while keeping individual vehicle components simple.
Solution Approach 2:
The patent replaces traditional mechanical positioning methods (such as track-based encoders or physical markers) with wireless UWB radio frequency measurements. The positioning system uses electromagnetic signal propagation characteristics (time of flight, time difference of arrival) to determine vehicle positions without mechanical contact or complex onboard positioning hardware, thereby improving accuracy while reducing overall system complexity.
2Productivity
If multiple container handling vehicles operate independently on the rail system, then operational flexibility is improved, but collision risk and space utilization efficiency worsen
Solution Approach 1:
The control system continuously receives real-time position data from the positioning nodes for all container handling vehicles and uses this feedback to dynamically adjust vehicle routes and speeds. When vehicles approach each other or when rail segments are occupied, the control system automatically modifies operational parameters to prevent collisions while maintaining high productivity. This closed-loop control enables multiple vehicles to operate independently yet safely in the same space.
Solution Approach 2:
The system dynamically adjusts vehicle operations based on real-time conditions. Vehicles can change speed, alter routes, or pause temporarily according to the current state of the rail system and other vehicles' positions. This dynamic adaptation allows maximum operational flexibility while maintaining safety, as vehicles respond continuously to changing conditions rather than following rigid predetermined schedules.
3Reliability
If real-time position data is continuously monitored for all vehicles, then collision prevention is improved, but data processing requirements and communication load worsen
Solution Approach 1:
The positioning system divides the storage facility into multiple zones monitored by distributed positioning nodes. Each node independently measures positions of vehicles within its range and reports only relevant data to the control system. This segmentation reduces the total data processing load compared to a centralized system that would process all raw signals from all nodes simultaneously, while still providing comprehensive collision prevention coverage throughout the entire facility.
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
Enables efficient and collision-free movement of multiple container handling vehicles by ensuring accurate positioning and coordinated movement, optimizing rail system space utilization.
Implementation Method 1
the positioning system being adapted to determine a position on the rail system for each of the container handling vehicles based on signal measurements between the positioning node of each container handling vehicle and the at least three reference positioning nodes
Implementation Method 2
a control system that uses time of flight (TOF) or time difference of arrival (TDOA) measurements to determine the precise positions of container handling vehicles
Data Source
AI summary
An automated storage and retrieval system includes a rail system with a first set of parallel rails extending in a first direction and a second set of parallel rails extending in second direction. The second direction is perpendicular to the first direction. The system includes a plurality of container handling vehicles on the rail system operable to handle storage containers. Each container handling vehicle includes a positioning node and a local controller adapted to control movements of the container handling vehicle. The system includes a positioning system comprising at least three reference positioning nodes spaced in fixed positions on and/or proximate the rail system. The positioning system is adapted to determine a position on the rail system for each of the container handling vehicles based on signal measurements between the positioning node of each container handling vehicle and the at least three reference positioning nodes. A control system is adapted to communicate with each local controller in each container handling vehicle and the positioning system. The control system is adapted to: instruct a first container handling vehicle to move to a target position, repeatedly receive position data from the positioning system of a position of the first container handling vehicle and repeatedly receive position data from the positioning system of a position of a second container handling vehicle, and instruct the second container handling vehicle to move with and follow the first container handling vehicle within a predetermined separation from the first container handling vehicle based on the received position data of the positions of the first and second container handling vehicles.