A Hopper was created to mimic a grasshopper's catapulting kicking action. Electroactive polymers (EAP) were investigated as actuators to simulate the grasshopper's lightweight and strong muscles. EAPs are lightweight materials that require low voltage and yield high force with short response times. This makes them a great potential source for future micro-robotic actuators. The EAP Actuator was simulated and the potential design was studied. The development of consistent and reliable actuation electrodes and nonconductive materials was considered. In addition, the current draw of the EAP Actuator was studied, current draw prediction equations were developed, and a force output study was conducted. Finally, the EAP Actuators were compared to other conventional actuators, including pneumatic actuators, for performance and weight requirements. The EAP Actuator will ultimately be a reliable and powerful actuator for un-tethered, lightweight robotic hoppers. The Hopper was simulated, built, and tested using pneumatic actuators. Each Hopper contained four actuators. The actuators' contraction and release were controlled by a Parallax Basic Stamp II microcontroller and 4 relays. A 9-volt battery, a 0-20 volt variable off board power supply, and a 60 psi off-board compressed air supply were required for operation. The Pneumatic Hopper results were compared to the EAP Hopper's analytical results. For both the Pneumatic and EAP Hoppers, the motion was modeled in Working Model Software. These computer-generated results were compared using Lumped Mass Equations in MatLab and Two Segmented Leg Robotic Hopper Equations presented by R. M. Alexander. The Pneumatic Hopper was then tested for performance. It ultimately yielded a hop height of 2.4 mm and an average hop range of 12.7 mm.
Library of Congress Subject Headings
Polymers--Electric properties; Actuators; Microelectromechanical systems; Conducting polymers; Robots--Design
Department, Program, or Center
Mechanical Engineering (KGCOE)
Bielmeier, Christie, "Exploration of an electroactive polymer actuator for application in a grasshopper inspired pneumatic robotic hopper" (2003). Thesis. Rochester Institute of Technology. Accessed from
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