I have my document like this (in main.tex):
% Document type: report (master/bachelor thesis)
\documentclass[a4paper,12pt,appendix]{report}
\input{template/FormatsAndDefs.tex} % here I have specified various format settings
\begin{document}
\input{thesis.tex}
\end{document}
In FormatsAndDefs.tex I have specified format for chapter titles like this:
\usepackage[T1]{fontenc}
\usepackage{titlesec}
% various other packages
\titleformat{\chapter}
{\normalfont\Large\bfseries}{\thechapter}{.5em}{\vspace{.5ex}}[\titlerule]
\titlespacing*{\chapter}
{0pt}{0pt}{15pt}
So my title chapters are formatted like this:

How can I make this chapter title "Introducion" in ALL UPPERCASE while keeping it bold and underlined?
I have tried to use \MakeUppercase :
\titleformat{\chapter}
{\normalfont\LARGE\bfseries}{\MakeUppercase{\thechapter}}{.5em}{\vspace{.5ex}}[\titlerule]
but chapter remained still the same as shown in the picture.


\MakeUppercasecommand. Does the second piece of code in Gonzalo Medina's answer to Formatting section titles help you? – Dai Bowen Nov 17 '16 at 00:28\MakeUppercasecommand in my\titleformatcode. – PeterB Nov 17 '16 at 00:39titlesecusing theexplicitoption as\usepackage[explicit]{titlesec}and then\titleformat{\chapter} {\normalfont\LARGE\bfseries}{\thechapter}{.5em}{\MakeUppercase{#1}\vspace{.5ex}}[\titlerule]. – Dai Bowen Nov 17 '16 at 01:02