Tyrannosaurus Rex Running? Estimations of Efficiency, Speed and Acceleration





Biological data analysis, Animal locomotion, Bipedal running, Fossil animals, Cost of motion, Met-abolic rate, Drag-to-weight ratio, Power-to-weight ratio


Background. The estimations of maximum speed of Tyrannosaurus Rex vary from 5 20 m/s and higher and still are the subject of scientific discussion. Some scientists consider T. Rex the largest terrestrial super-predator that needed speeds greater than60 km/h (17 m/s) to capture its prey. Some recent publications indicate that it wasn’t able to run at all due to its large mass and significant loads on the skeleton and limit its walking speed to 5–7.5 m/s.

Objective. We will try to answer the question of whether large animal or robot sizes are an obstacle to rapid running and to evaluate the maximum possible speed of T. Rex.

Methods. We will use: a) two energy efficiency indicators - the drag-to-weight ratio or the cost of motion and the recently developed capacity-efficiency (connected with the power-to-weight ratio or metabolic rate); b) the vertical acceleration estimations; c) the available data about the speed, the stride and the leg length of human and animals.

Results. The drag-to-weight ratio and the capacity-efficiency were estimated for running of different animals and humans. It was shown that the maximal running speed of T. Rex may reach the values 21–29 m/s. The values of its vertical acceleration are typical for bipedal running.

Conclusions. Large dimensions of Tyrannosaurus Rex couldn’t be an obstacle to achieving rather high speeds during short intervals of fast running. Such conclusions allow us not to abandon the assertion that the dinosaur was a super-predator. Presented approach could be useful for studying locomotion in modern and fossil animals, human sport activity and for design of fast bipedal robots.

Author Biography

Igor Nesteruk, Institute of Hydromechanics, NAS of Ukraine; Igor Sikorsky Kyiv Polytechnic Institute

Игорь Георгиевич Нестерук


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How to Cite

Nesteruk I. Tyrannosaurus Rex Running? Estimations of Efficiency, Speed and Acceleration. Innov Biosyst Bioeng [Internet]. 2018Apr.2 [cited 2021Oct.23];2(1):42-8. Available from: http://ibb.kpi.ua/article/view/120491