1、 - 1 - Biologically Inspired Locomotion Strategies: Novel Ground Mobile Robots at RoMeLa Abstract-This paper presents some of the ground mobile robots under development at the Robotics and Mechanisms Laboratory (RoMeLa) at Virginia Tech that use biologically inspired novel locomotion strategies. By
2、studying natures models and then imitating or taking inspiration from these designs and processes, we apply and implement new ways for mobile robots to move. Unlike most ground mobile robots that use conventional means of locomotion such as wheels or tracks, these robots display unique mobility char
3、acteristics that make them suitable for certain environments where conventional ground robots have difficulty moving. These novel ground robots include； the whole skin locomotion robot inspired by amoeboid motility mechanisms, the three-legged walking machine STriDER (Self-excited Tripedal Dynamic E
4、xperimental Robot) that utilizes the concept of actuated passive-dynamic locomotion, the hexapod robot MARS (Multi Appendage Robotic System) that uses dry-adhesive “gecko feet” for walking in zero-gravity environments, the humanoid robot DARwIn (Dynamic Anthropomorphic Robot with Intelligence) that
5、uses dynamic bipedal gaits, and the high mobility robot IMPASS (Intelligent Mobility Platform with Active Spoke System) that uses a novel wheel-leg hybrid locomotion strategy. Each robot and the novel locomotion strategies it uses are described, followed by a discussion of their capabilities and cha
6、llenges. Keywords - Bio-inspiration, locomotion, mobile robots. 1. Introduction In a report 1 prepared for the Office of the Secretary of Defense Joint Robotics - 2 - Program on the lessons learned from the robot assisted search and rescue efforts at Ground Zero following the 9/11 World Trade Center
7、 tragedy, robot mobility is noted as one of the major limitations of current robotic technology for such missions. The report further states that all the robots employed at the Ground Zero site used track drives which are generally superior to wheels on uneven ground； however, other alternative loco
8、motion strategies which are more effective must be further investigated. Unlike aerial or marine vehicles which can reach almost any destination point in their travel domain, most ground vehicles used today have difficulty traversing overobstacles and climbing steep inclines due to their limited mob
9、ility, especially in unstructured environments. As the technology of robotics intelligence advances, and new application areas for mobile robots increase, the need for alternative fundamental locomotion mechanisms for robots that can enable them to maneuver into complex unstructured terrain becomes
10、critical. Current methods of ground vehicle locomotion are based on wheels, tracks or legs, and each of these methods has its own strengths and weaknesses 2, 3. In order to move a robot into an area of complex terrain a new method of locomotion is needed. For example, to be able to find people trapp
11、ed in a collapsed building, a robot would need to be able to move over, under and between rubble, and maneuver itself into tight corners. Current methods of locomotion can do some part of this, but they have only had limited success in achieving all of these capabilities 4. By studying natures model
12、s and then imitating or taking inspiration from these designs and processes, we apply and implement new ways for mobile robots to move. In this paper we present five of the ground mobile robots under development at the Robotics and Mechanisms Laboratory (RoMeLa) at Virginia Tech that use biologicall
13、y inspired novel locomotion strategies. Unlike most ground mobile robots that use conventional means of locomotion such as wheels or tracks, these robots display unique mobility characteristics - 3 - that make them suitable for certain environments whereconventional ground robots have difficulty mov
14、ing. 2. Biologically Inspired Novel Locomotion Strategies 2.1 Locomotion inspired by amoeboid motility mechanisms Whole Skin Locomotion (WSL) 5, 6 is a biologically which has a body of a shape of an elongated torus, is used as a surface for traction and that the skin is used for the actuation by cyc
15、ling through contraction and expansion. Fig. 1. Motility mechanism of a monopodial amoeba The inspiration for this novel locomotion strategy comes from the way certain single celled organisms, such as the Amoeba proteus (giant amoeba) move. The motion of these organisms is caused by the process of c
16、ytoplasmic streaming (Fig. 1) where the liquid form endoplasm that flows inside the ectoplasmic tube transforms into the gel-like ectoplasm outer skin at the front, and the ectoplasm outer skin at the end transforms back into the liquid form endoplasm at the rear. The net effect of this continuous e
17、ctoplasm-endoplasm transformation is the forward motion of the amoeba 7, 8. Directly imitating this cytoplasmic streaming process with a robot is very difficult to do if not possiblee. Thus, instead of using the process of liquid to gel transformation of cytoplasm, the WSL is implemented by a flexible membrane skin in the shape of a long torus. The skin of this elongated torus can then rotate in a fashion of turning itself inside out in a single continuous motion, effectively generating the overall motion of the cytoplasmic streaming
