Photo: Drexel University.
For paleontologists who want to know how a 60 to 70 ton dinosaur got around, the lack of subjects to study is a bit
of an obstacle. However, at Drexel University, researchers are
3D printing small scale robotic models of the legs of one of
the largest dinosaurs ever found to figure out how it was able
to keep itself moving.
Dreadnoughtus schrani, which weighed an estimated 65
tons ( 60,000 kg), is the most massive land animal whose size
can be confidently calculated, according to Drexel University
scientists. In life, Dreadnoughtus was a herbivore that likely
spent much of its life eating massive quantities of plants to
maintain its enormous body size.
Fossils of Dreadnoughtus schrani were discovered in
Argentina in 2005. This dinosaur (a species of
titanosaur) is estimated to have been the same
approximate size and weight of a Boeing 737, although
the example that was found was only a juvenile and
not yet done growing. The femur that was dug up is a
massive 1.8 meters in length, meaning that the dino
stood about two stories tall at the shoulder and was
probably something like 26 meters long.
Drexel University scientists say Dreadnoughtus
schrani was substantially more massive than any other
large dinosaur for which mass can be accurately
The closest animal equivalent we have right now
to this dinosaur is an elephant, and an elephant really
isn’t a very close equivalent at all (see the comparison
chart). Dreadnoughtus was quite possibly the largest
land animal that ever lived, and it’s a case study (albeit an
extinct one) in what happens when a biological system
reaches the top end of what’s possible with mass
supported on legs.
To figure out how Dreadnoughtus managed to walk,
Drexel researchers have 3D scanned Dreadnoughtus leg
bones, fixed the damage caused by 77 million years (give
or take) of being part of a rock, reduced it to a
manageable size, and 3D printed the result.
There are some features on the fossils themselves
that show where tendons and muscles might have been
attached, and modern dinosaurs like chickens (seriously)
provide additional physiological suggestions. However,
cartilage is trickier, and this is where the robot limb can
By 3D printing cartilage and then attaching everything
together with some motors, the physical model can be
actuated and then analyzed with more accuracy than
would be possible using a computer simulation.
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Drexel University scientists say Dreadnoughtus schrani was substantially more
massive than any other large dinosaur for which mass can be accurately
calculated. Illustration: Lacovara Lab/Drexel University.
Illustration: Jennifer Hall/Drexel University.