Advancements in software engineering have enabled the robotics industry to transition from the use of giant industrial robots to more friendly humanoid robots. Soft robotics is one of the key elements needed to advance the transition process by providing a safer way for robots to interact with the environment. Electroactive polymers (EAPs) are one of the best candidate materials for the next generation of soft robotic actuators and artificial muscles. Lightweight dielectric elastomer actuators (DEAs) provide optimal properties such as high elasticity, rapid response rates, mechanical robustness and compliance. However, for DEAs to become widely used as artificial muscles or soft actuators, there are current limitations, such as high actuation voltage requirements, control of actuation direction, and scaling, that need to be addressed. The authors’ approach to overcome the drawbacks of conventional DEAs is inspired by the natural skeletal muscles. Instead of fabricating a large DEA device, smaller sub-units can be fabricated and bundled together to form larger actuators, similar to the way myofibrils form myocytes in skeletal muscles. The current study presents a novel fabrication approach, utilizing soft lithography and other microfabrication techniques, to allow fabrication of multilayer stacked DEA structures, composed of hundreds of micro-sized DEA units.

No abstract

No abstract

In recent years I have been teaching a project-based Robotics course within our quarterbased Mechanical Engineering program using the Stamp microcontroller. Students work in teams to complete a number of weekly lab exercises designed to sufficiently build their robotics expertise to the level that they can complete a project to design, build, and test an autonomous mobile robot to successfully complete an assigned task of their choosing. The course was structured in such a way that course materials laid out everything explicitly for the students since time was short on a ten-week quarter schedule. They simply followed the directions given. This fall, we changed to a semester schedule, changed our microcontroller from the Stamp to the popular Arduino, and restructured the entire course. Since extensive information is available on-line and in the literature for the Arduino, the course philosophy and structure has changed. Instead of providing students with all the information they need, students are now presented with a task, and they are told to go discover how to do it. As a result, the course is more challenging and interesting for them. This is aided by the additional time available in the semester schedule and by the wealth of information available for the Arduino. The paper discusses the current structure of the course, how independent team effort is evaluated, and the problems encountered in switching from a Stamp-based ten week quarter course to an Arduino-based "self-discovery" semester course.

The loss of a hand can greatly affect quality of life. A prosthetic device that can mimic normal hand function is very important to physical and mental recuperation after hand amputation, but the currently available prosthetics do not fully meet the needs of the amputee community. Most prosthetic hands are not dexterous enough to grasp a variety of shaped objects, and those that are tend to be heavy, leading to discomfort while wearing the device. In order to attempt to better simulate human hand function, a dexterous hand was developed that uses an over-actuated mechanism to form grasp shape using intrinsic joint mounted motors in addition to a finger tendon to produce large flexion force for a tight grip. This novel actuation method allows the hand to use small actuators for grip shape formation, and the tendon to produce high grip strength. The hand was capable of producing fingertip flexion force suitable for most activities of daily living. In addition, it was able to produce a range of grasp shapes with natural, independent finger motion, and appearance similar to that of a human hand. The hand also had a mass distribution more similar to a natural forearm and hand compared to contemporary prosthetics due to the more proximal location of the heavier components of the system. This paper describes the design of the hand and controller, as well as the test results.