What version of FileMaker are you using?
I'm using FileMaker Pro 12.
Ever used the ExecuteSQL function? This one seems made to order for using the delimited data data source option with executeSQL used to produce the delimited data needed for your chart.
I haven't used that function before. Any advice on how to proceed?
I can provide some resources and a basic outline of what you might try but whether the "learning curve" will be steep or gentle depends on your prior knowledge and tech skill set.
A resource document from FileMaker on SQL queries: https://fmhelp.filemaker.com/docs/13/en/fm13_sql_reference.pdf
SeedCode's SQL Explorer: http://www.seedcode.com/cp-app/ste_cat/sqlxfree This file can build your SQL query text for you.
A link on using ExecuteSQL to produce a list of subtotals: FMP 12 Tip: Summary Recaps (Portal Subtotals)
The basic concept is to produce two lists of values separated by returns (¶). The "wedge labels" series can be something as simple as List ( "R & D Lab" ; "Analytical" )
The Wedge Width series would use Sum and GROUPBY to produce a matching pair of sub totals.