Ceiling Conveyance Vehicle Controller Logic for Semiconductor FOUP Handling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing conveyance systems in semiconductor manufacturing factories have a low possibility of establishing a supplying-and-collecting operation due to accidental timing of ceiling traveling vehicles conveying objects, leading to inefficiencies and degradation in conveyance efficiency.
Innovation Solution
A conveyance system with a controller that waits to output a collection instruction for a conveyed object until a conveyance vehicle conveying another object to an upstream port is recognized, thereby increasing the possibility of allocating the collection instruction to the correct vehicle and reducing waiting time, thus enhancing the operating efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If the controller immediately outputs a collection instruction when a conveyed object is placed on the downstream port, then the conveyance speed is improved, but the possibility of establishing a supplying-and-collecting operation decreases
Solution Approach 1:
The controller performs preliminary checking before outputting the collection instruction. It checks whether a conveyance vehicle conveying another conveyed object to the upstream port has been recognized, and only outputs the collection instruction when this condition is met. This preliminary action ensures that the same vehicle can perform both supply and collection operations, establishing a supplying-and-collecting operation while maintaining efficient conveyance.
2Productivity
If the controller waits for a conveyance vehicle to be recognized before outputting the collection instruction, then the operating efficiency is improved, but the conveyance time increases
Solution Approach 1:
The controller continuously monitors and receives recognition information from conveyance vehicles in real-time. When a vehicle conveying another object to the upstream port is recognized, the controller immediately outputs the collection instruction for the first conveyed object. This feedback mechanism ensures that the waiting time is minimized while still establishing supplying-and-collecting operations, balancing operating efficiency with conveyance time.
3Productivity
If the controller outputs collection instructions frequently, then the conveyance efficiency is improved, but the possibility of allocating instructions to the correct vehicle decreases
Solution Approach 1:
The controller performs a preliminary check before outputting the collection instruction to verify that a conveyance vehicle conveying another conveyed object to the upstream port has been recognized. This preliminary action ensures that the collection instruction is allocated to the correct vehicle that is already in position, maintaining both high conveyance efficiency and accurate instruction allocation.
Solution Approach 2:
The controller uses real-time feedback from vehicle recognition to determine when to output collection instructions. By waiting for confirmation that a vehicle is recognized and in the correct position, the controller ensures accurate instruction allocation while maintaining efficient operation through timely instruction output.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A conveyance system includes a track, ceiling conveyance vehicles, and a conveyance controller configured or programmed to output a conveyance instruction for a FOUP to the ceiling conveyance vehicles. When a first FOUP on a downstream port is in a state waiting for collection, and when a FOUP is not placed on an upstream port, the conveyance controller waits without outputting a conveyance instruction instructing collection of the first FOUP until any of the conveyance vehicles conveying a second FOUP to the upstream port has been recognized until a waiting time set in advance has elapsed since the first FOUP changed to the state waiting for collection and outputs the conveyance instruction instructing collection of the first FOUP when the waiting time has elapsed since a point in time when the first FOUP changed to the state waiting for collection.