. A "modular" robotic system consists of standardized joint and link units that can be assembled into a number of different kinematic configurations in order to meet different task requirements. Given a predetermined set of modules, this paper considers the problem of finding an "optimal" module assembly configuration for a specific task. We formulate the solution as a discrete optimization procedure. The formulation is based on an assembly incidence matrix representation of a modular assembly configuration and a general task-oriented objective function that can incorporate many realistic task criteria. Genetic algorithms (GA) are employed to solve this optimization problem, and a canonical method to represent a modular assembly in terms of genetic strings is introduced. An example involving a 3-DOF manipulator configuration is presented to demonstrate the feasibility of this approach. 1. Introduction A modular reconfigurable robotic system is a collection of various sub-assemblies,...

Robot configuration design is hampered by the lack of established, well-known design rules, and designers cannot easily grasp the space of possible designs and the impact of all design variables on a robot’s performance. Realistically, a human can only design and evaluate several candidate configurations, though there may be thousands of competitive designs that should be investigated. In contrast, an automated approach to configuration synthesis can create tens of thousands of designs and measure the performance of each one without relying on previous experience or design rules. This thesis creates Darwin2K, an extensible, automated system for robot configuration synthesis. This research focuses on the development of synthesis capabilities required for many robot design problems: a flexible and effective synthesis algorithm, useful simulation capabilities, appropriate representation of robots and their properties, and the ability to accomodate application-specific synthesis needs. Darwin2K can synthesize and optimize kinematics, dynamics, structural geometry, actuator selection, and task and control parameters for a wide range of robots.

Abstract—The field of evolutionary robotics has demonstrated the ability to automatically design the morphology and controller of simple physical robots through synthetic evolutionary processes. However, it is not clear if variation-based search processes can attain the complexity of design necessary for practical engineering of robots. Here, we demonstrate an automatic design system that produces complex robots by exploiting the principles of regularity, modularity, hierarchy, and reuse. These techniques are already established principles of scaling in engineering design and have been observed in nature, but have not been broadly used in artificial evolution. We gain these advantages through the use of a generative representation, which combines a programmatic representation with an algorithmic process that compiles the representation into a detailed construction plan. This approach is shown to have two benefits: it can reuse components in regular and hierarchical ways, providing a systematic way to create more complex modules from simpler ones; and the evolved representations can capture intrinsic properties of the design space, so that variations in the representations move through the design space more effectively than equivalent-sized changes in a nongenerative representation. Using this system, we demonstrate for the first time the evolution and construction of modular, three-dimensional, physically locomoting robots, comprising many more components than previous work on body-brain evolution. Index Terms—Design automation, evolutionary robotics, generative representations. I.

There exists a need for manipulators that are more flexible and reliable than the current fixed configuration manipulators. Indeed, robot manipulators can be easily reprogrammed to perform different tasks, yet the range of tasks that can be performed by a manipulator is limited by its mechanical structure. In remote and hazardous environments, such as a nuclear facility or a space station, the range of tasks that may need to be performed often exceeds the capabilities of a single manipulator. Moreover, it is essential that critical tasks be executed reliably in these environments. To address this need for a more flexible and reliable manipulator, we propose the concept of a rapidly deployable fault tolerant manipulator system. Such a system combines a Reconfigurable Modular Manipulator System (RMMS) with support software for rapid programming, trajectory planning, and control. This allows the user to rapidly configure a fault tolerant manipulator custom-tailored for a given task. This ...

Long development times and high costs prevent robots from being practical for use in many important field missions. Here a modular design approach is proposed to produce a rapidly deployable low cost field robotic system. An inventory of components such as actuated joints, links, power supplies, and software modules are assembled to produce a field robotic system for a specified task. The proposed design method uses a hierarchical selection process combined with a genetic algorithm to select a robot configuration and action plan for a given task. This method is applied to an inspection task required for the preservation of the USS Constitution, an historic naval ship. 1. Introduction Mobile robots are needed to perform important tasks in field environments. Robots could remove humans from dangerous situations such as hazardous material clean-up, nuclear site inspection, bomb disposal, space exploration, and infrastructure inspection. Potentially, robots could prove economical for suc...

We have developed miniature direct drive DC motor actuators for robotics. These actuators have low friction, small size, high speed, low construction cost, no gear backlash, operate safely without the use of limit switches and generate moderate torque at a high torque to weight ratio. Our initial experiments indicated the feasibility of constructing a variety of new high speed low cost actuators, for applications in camera pointing, robot hands, and robot legs. In this work we study some prototype devices in each of these categories. 1 Introduction Electromagnetic devices remain the most viable form of robot actuator, due to their relatively high strength, their well understood characteristics, the ease of interfacing them to electronic control circuits, and the nearly universal availability of electricity as a power source. Moreover, there is ongoing steady advance in electric motor component technology including permanent magnets, permeable materials, power transistors, bearings and...

We present Darwin2K, a widely-applicable, extensible software tool for synthesizing and optimizing robot configurations. The system uses an evolutionary optimization algorithm that is independent of task, metrics, and type of robot, enabling the system to address a wide range of synthesis problems. Darwin2K can synthesize fixed-base and mobile robots (including free-flying robots, mobile manipulators, modular robots, and multiple or bifurcated manipulators), and includes a toolkit of simulation and analysis algorithms which are useful for many synthesis tasks. Some of these capabilities, such as dynamic simulation, are novel in automated synthesis of robots. An extensible software architecture enables new synthesis tasks to be addressed while maximizing use of existing system capabilities; this

any required final revisions, as accepted by my examiners. I understand that my thesis may be made electronically available to the public. Modular and Reconfigurable Robots (MRRs) are those designed to address the increasing demand for flexible and versatile manipulators in manufacturing facilities. The term, modularity, indicates that they are constructed by using a limited number of interchangeable standardized modules which can be assembled in different kinematic configurations. Thereby, a wide variety of specialized robots can be built from a set of standard components. The term, reconfigurability, implies that the robots can be disassembled and rearranged to accommodate different products or tasks rather than being replaced. A set of MRR modules may consist of joints, links, and end-effectors. Different kinematic configurations are achieved by using different joint, link, and end-effector modules and by changing their relative orientation. The number of distinct kinematic configurations, attainable by a set of modules, varies with respect to the size of the module set from several tens to several thousands. Although determining the most suitable configuration for a specific task from