Multi-Leaf Collimator Leaf Segmentation for Weight Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing multi-leaf collimators for radiotherapy apparatuses are heavy, expensive, and difficult to process due to the use of high-atomic-number materials like tungsten for all leaf portions, including those not required for radiation attenuation.
Innovation Solution
The leaf for a multi-leaf collimator is designed with a leaf portion for radiation attenuation made from a high-atomic-number material and a tail portion made from a different, lighter, and easier-to-machine material, reducing the overall weight and cost while maintaining effective radiation attenuation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the entire leaf is made from high-atomic-number material (tungsten), then radiation attenuation is maximized, but weight and cost increase and manufacturing difficulty increases
Solution Approach 1:
The leaf is divided into two functional segments: a leaf portion (first area) made from high-atomic-number material for radiation attenuation, and a tail portion (second area) made from different material for mechanical functions. This segmentation allows each part to be optimized for its specific purpose, reducing overall weight while maintaining attenuation effectiveness.
Solution Approach 2:
Different parts of the leaf are assigned different material properties according to their functional requirements. The leaf portion uses high-atomic-number material where radiation attenuation is critical, while the tail portion uses alternative material where mechanical properties are sufficient. This local differentiation optimizes the weight-to-performance ratio.
2Reliability
If the entire leaf is made from high-atomic-number material (tungsten), then radiation attenuation is maximized, but manufacturing difficulty increases
Solution Approach 1:
The leaf is segmented into a leaf portion requiring high-atomic-number material for radiation attenuation and a tail portion that can be made from easier-to-manufacture materials. This allows complex features to be machined in the tail portion using standard materials, while the leaf portion is optimized for radiation blocking.
Solution Approach 2:
The leaf is constructed as a composite structure combining different materials: high-atomic-number material for the leaf portion and alternative material for the tail portion. This composite approach leverages the advantages of each material where needed, balancing radiation attenuation performance with manufacturing ease.
3Reliability
If the entire leaf is made from high-atomic-number material (tungsten), then radiation attenuation is maximized, but cost increases
Solution Approach 1:
The leaf is divided into a leaf portion made from expensive high-atomic-number material where radiation attenuation is critical, and a tail portion made from less expensive alternative materials. This segmentation reduces overall material cost while maintaining the necessary attenuation performance in the critical region.
Solution Approach 2:
High-atomic-number material is applied locally only where radiation attenuation is required (in the leaf portion), rather than throughout the entire leaf. This localized application minimizes material costs while preserving the essential function, and allows the tail portion to be manufactured at lower cost.
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 design reduces the weight and cost of the multi-leaf collimator while maintaining effective radiation attenuation, improving manufacturing ease and reducing interference between leaf drive components.
Implementation Method 1
the leaves are made from a high atomic numbered material, usually tungsten, so that they are substantially opaque to the radiation
Data Source
AI summary
A leaf for a multi-leaf collimator comprises a leaf portion for delineating a beam of radiation, the leaf portion having first attenuation factor. The leaf also comprises a tail portion having a second attenuation factor, the first attenuation factor being greater than the second attenuation factor.