Size comparison of the North American ankylosaur Gastonia burgei, scaled to the holotype. The silhouette was primarily drawn following Hartman's skeletal, though some details (notably the pelvic shield) follow illustrations in Kinneer et al. (2016). The human silhouette is 180 cm (5.9 ft) tall and is from File:Silhouette of man standing and facing forward.svg (CC0).
References
Skeletal diagram by Scott Hartman
Kinneer, B.; Carpenter, K.; Shaw, A. (2016). "Redescription of Gastonia burgei (Dinosauria: Ankylosauria, Polacanthidae), and description of a new species". Neues Jahrbuch für Geologie und Paläontologie-Abhandlungen 282 (1): 37–80.