Academic Journal of Engineering and Technology Science, 2026, 9(2); doi: 10.25236/AJETS.2026.090214.
Wenjie Li1, Biao Wang1
1University of Science and Technology Liaoning, Anshan, China
The ruler cannon is a simple physics experiment device that converts elastic potential energy into kinetic energy. This paper adopts a core model consisting of two elastic rulers clamping a small ball, and systematically investigates the effects of factors such as applied force magnitude, ball mass, ruler angle, and force application position on the launch velocity of the ball, using nonlinear elasticity theory as well as the theorems of rigid-body translation and rotation. A complete set of motion equations, including normal force, friction, torque, and moment of inertia, is established through theoretical analysis. In the experiments, high-speed photography and trajectory methods are employed to measure the launch velocity and displacement of the ball. The results show that, due to its higher Young’s modulus, a steel ruler stores elastic potential energy more efficiently than a plastic ruler. The launch velocity of the ball exhibits a non-monotonic variation with increasing external force. The farther the force application position is from the initial contact point of the ball, the higher the force transmission efficiency. As the ball mass increases, the launch velocity decreases. This study provides a theoretical basis and experimental support for the optimal design of elastic launch systems.
elastic deformation; energy conversion; friction distribution; nonlinear elasticity
Wenjie Li, Biao Wang. Research on Dynamic Characteristics and Parameter Optimization of the Elastic Launch System of the Ruler Cannon. Academic Journal of Engineering and Technology Science (2026), Vol. 9, Issue 2: 103-109. https://doi.org/10.25236/AJETS.2026.090214.
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