diff --git a/Doc_images/USG internal diagram.png b/Doc_images/USG internal diagram.png new file mode 100644 index 0000000..056b90a Binary files /dev/null and b/Doc_images/USG internal diagram.png differ diff --git a/Doc_images/USG usage diagram.png b/Doc_images/USG usage diagram.png new file mode 100644 index 0000000..21dd462 Binary files /dev/null and b/Doc_images/USG usage diagram.png differ diff --git a/Doc_images/USG.jpg b/Doc_images/USG.jpg new file mode 100644 index 0000000..297bdcd Binary files /dev/null and b/Doc_images/USG.jpg differ