On the Biomimetic Design of Agile-Robot Legs

The development of functional legged robots has encountered its limits in human-made actuation technology. This paper describes research on the biomimetic design of legs for agile quadrupeds. A biomimetic leg concept that extracts key principles from horse legs which are responsible for the agile and powerful locomotion of these animals is presented. The proposed biomimetic leg model defines the effective leg length, leg kinematics, limb mass distribution, actuator power, and elastic energy recovery as determinants of agile locomotion, and values for these five key elements are given. The transfer of the extracted principles to technological instantiations is analyzed in detail, considering the availability of current materials, structures and actuators. A real leg prototype has been developed following the biomimetic leg concept proposed. The actuation system is based on the hybrid use of series elasticity and magneto-rheological dampers which provides variable compliance for natural motion. From the experimental evaluation of this prototype, conclusions on the current technological barriers to achieve real functional legged robots to walk dynamically in agile locomotion are presented

Robotic design and modelling of medical lower extremity exoskeletons

This study aims to explain the development of the robotic Lower Extremity Exoskeleton (LEE) systems between 1960 and 2019 in chronological order. The scans performed in the exoskeleton system’s design have shown that a modeling program, such as AnyBody, and OpenSim, should be used first to observe the design and software animation, followed by the mechanical development of the system using sensors and motors. Also, the use of OpenSim and AnyBody musculoskeletal system software has been proven to play an essential role in designing the human-exoskeleton by eliminating the high costs and risks of the mechanical designs. Furthermore, these modeling systems can enable rapid optimization of the LEE design by detecting the forces and torques falling on the human muscles

Design Concepts for a Hybrid Swimming and Walking Vehicle

AbstractThis paper describes the design and proposed control methods for a 6-legged swimming and walking robot that can be used in a variety of different transportation and equipment control applications above ground, under water and above water. Known as the TURTLE (Tele–operated Unmanned Robot for Telemetry and Legged Exploration), a prototype of this mobile robot is currently being designed and developed for experimental testing in the near future. It will be powered by rechargeable electric batteries (to be recharged by solar panels) and all of its actuators will be electric motors, each controlled and monitored by onboard microcontrollers supervised by an onboard master computer. The TURTLE will be fitted with several high-resolution digital cameras, 3D laser and sonar scanners, an IMU (Inertial Management Unit), electronic compass, GPS (satellite navigation) module, underwater sonar transceiver hardware and two or more types of long-distance wireless communications hardware. The first prototype of the TURTLE will focus on basic tasks such as remote video surveillance, 3D terrain surface scanning (above ground and underwater), basic swimming styles, basic walking styles, climbing over large rocks and walking over very rough ground and steep terrain. This paper describes the main objectives, basic performance specifications, functions and mechanical design solutions that have been developed so far for this project. It covers details of the various different swimming modes and feasible solutions for achieving the main design objectives

Feasibility of integrating multiple types of electroactive polymers to develop a biomimetic inspired muscle actuator

The focus of this project is to see if it is possible to integrate multiple EAP materials in an electro- mechanical system to produce a closer representation of a biological muscle with smooth varying motion. In this preliminary study, two common types of EAPs, ionic and dielectric, were investigated to determine their mechanical and electrical properties in order to assess their potential to be combined into a working artificial electromechanical muscle prototype at a later time. A conceptual design for an artificial electromechanical muscle was created with biomimetic relationships between EAP materials and the human bicep muscle. With the assistance of the Rochester General Hospital, a human arm model, isolating the bicep muscle, was created to calculate mechanical characteristics of the bicep brachii. From the human arm model, bicep muscle characteristics were compared to those of the dielectric EAP because of the ability for the EAP to output relatively high force and strain during actuation. It was found that the current state of the art of EAPs is a long way from making this a reality due to their limiting force output and voltage requirements. The feasibility of developing an artificial electromechanical muscle with EAP actuators is not possible with current technology