Return a local variable from a Module containing a Manipulate

Question

I would like to create a set of custom controls that call Manipulate[] and return the value(s) set during the Manipulate session.

I can easily make a version that uses something like:

MyControl[] := Manipulate[...{a, -10,10}, {b,-1,1}]

This works but variables a, b and any additional variables set by Manipulate are global.

Is it possible to do something like this (Return a Dataset with the selected values for a and b when a "Set" button is clicked and Return Null if "Forget" is clicked):

MyControl[]:= Module[ {a, b},
                      Manipulate[...{a, -10, 10}, {b, -1, 1},
                                 Button["Set", Return[Dataset[Association @ {aValue->a, bValue->b}]]],
Button["Forget", Return[]]]]

Answer 1

Are you certain that a and b in the first example are Global? In version 10 they do not appear to be:

(The sliders of one Manipulate do not affect those of the other.)

A look at the Cell Expression for one of these shows:

. . . DynamicModuleBox[{$CellContext`a$$ = -3.3999999999999995`, $CellContext`b$$ = 
0.21999999999999997`, . . .] . . .

It would seem that these are already localized with DynamicModule.