Hexplorer is a six-legged walking robot developed at the University of Waterloo. The robot is controlled by a network of seven digital signal processors, six of which control three motors each, for a total of 18 motors. Brand new custom electronics were designed to house the digital signal processors and associated circuitry. A variable duty factor wave gait, developed by Yoneda et al. was simulated and implemented on the robot. Simulation required an in-depth kinematic analysis that was complicated by the mechanical design of parallel mechanism comprising the legs. These complications were handled in both simulation and implementation. However, due to mechanical issues Hexplorer walked for only one or two steps at a time.

This thesis presents a detailed design, calibration, and control of a modular and reconfigurable robot (MRR) system. A MRR system not only includes modular mechanical hardware, but also modular electrical hardware, control algorithms and software. Also, those modular components can be easily constructed into various manipulator configurations to accomplish a wider range of tasks. MRRs represent the next generation of industrial manipulators that cope with the transition from mass to customer-oriented production. The main contributions of this thesis are: 1) mechanical design and calibration of multi-input multi-output (MIMO) joint modules of MRR, and 2) control design to handle multiple configuration and overcome disturbance due to dynamics uncertainty. From the mechanical design point of view, this thesis presents two main topics: 1) each joint is not only modularly designed, but also has multiple-input multiple-output (MIMO) physical connection ports, which contributes to the concept of reconfigurability. Strictly speaking, single-input single-output (SISO) modular joint falls into the category of modular manipulator, and the robot reconfiguration is achieved by integrating different types of modules. For example, with single revolute MIMO joint module, both rotary and pivotal joint can be generated. On the other hand, if you would like to switch from rotary movement to pivotal movement with a SISO joint module, using another pivotal joint module is the only way to achieve this goal, and 2) for precise automation application, joints and links should be accurately connected and oriented when reconfigured. Our proposed modular joint has four connection ports which can be configured as either a rotary joint or a pivotal joint. In addition, key and keyway connection mechanism provides high accuracy in positioning the link onto the joint. Therefore, this structure reduces or eliminates MRRs system calibration time when reconfigured. Furthermore, zero link offset when used as a pivotal joint increases the robot dexterity, maximizes the reachability, and results in kinematics simplicity. The main challenge in the control of an MRR system with harmonic drives (HD) is the significant uncertainties due to friction, unmodelled dynamics, varying payload, gravitation, dynamic coupling between motions of joints, and the configuration changes. In order to compensate all unpredictable effects, we proposed a decentralized saturation-type robust control scheme based on direct-Lyapunov method and backstepping techniques. To better understand the system dynamics behavior, the HD flexspline compliance and friction calibration and results are also provided. The results are used for controller design. The proposed controller is verified through both computer simulation and experimental analysis.

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The work explores the possibility to increase the automation along a production line by introducing robots without reducing the safety of the operator. The introduction of a robot to a workstation often demands a redesign of the workstation and traditionally the introduction of physical safety solutions that can limit the access to the work area and object on the production line. This work aims to find a general solution that can be used not only in the construction industry, but also in other types of industries to allow for an increased Human and Robot Interaction (HRI) without physical safety solution. A concept solution of a dynamic and flexible robot cell is presented to allow for HRI based on safety zones in a shared work environment. The concepts are based on one robot and the usage of a 3D camera system allowing for the design of virtual safety zones, used to control the HRI. When an operator approaches the robots work area and triggers a safety zone the robot stops its work and moves away from the operator. Based on the safety requirements and triggered zones the robot will continue to work in a new area or wait until the operator leaves the work area and then continue with the interrupted work task. This will allow the operator and the robot to work together, where the operator location controls the robots workspace. Testing and validation of the presented concept showed that the wanted functionality could be obtained. It also showed limitations to the equipment and the system used during tests and raised additional aspects of the safety for HRI. Of the detected limitations the most crucial when looking at up-time for the production line, is the camera system need of a relatively dust free environment, good and constant lighting. For the safety of the system the limitation lies in the size and placing of the safety zones in combination with the disturbance from  surrounding equipment. The presented concept has proven to work, and can be applied not only for the construction industry but for all industries with manufacturing alongside production lines with large components.

Ljunghäll AB in Södra Vi has many industrial robots in their casting production. These robots have a tendency to wear out. The purpose with this thesis was to design a toolholder that was able flip to a 90 degree angle to get a more flexible production but also to lessen the wear on the robot. Parts of David G. Ullman and Ulf Liedholm’s design processes was used as a base for the solutions and the conceptual design. A number of concepts where made and one of them evaluated to be a refined concept. The result became a tool-holder that used an air-motor and two spur gears to rotate the plate where the tool is mounted to a 90 degree angle. According to the calculations that was made, both by hand and by the computer program COSMOS, the concept should work in practice. A prototype ought to be made to guarantee the function of the concept.

The aim of this essay is to describe the development of two prototypes, a physical one and a computer one, for a ball game involving interaction with an industrial robot.The purpose of the game is to attract young people, especially young women, to engineering, for amusement or education, at exhibitions or other student environments. This project in Product Design Engineering was initiated by the Centre for Intelligent Automation, a research group of Skövde University who offered the task in cooperation with two other areas of engineering, i.e Automation Engineering and Computer Science. The entire robot game project was developed by a five-woman team, which resulted in three different projects belonging to each study. The design engineering task was carried out by analysing the component needs, taking in consideration all the important factors involved, to recognize problems and limitations, and focus on prototypes. The development process included concept generation and evaluation, prototyping and detail design and testing and refinement of the physical prototype. As a result the prototype showed an intuitive way to play the game, and a 3D CAD model was developed to show an alternative design which found solutions to some of the problems shown by the physical one.

Typically, when Faurecia in Torsås are planning a new assembly line, one of the steps is to build a full-scale model of the line in card board, a form of mock-up planning. Faurecia has shown interest in finding an alternative methodology. The purpose was to explore the possibility of replacing today's cardboard based mock-up planning with models in a digital simulation environment. The purpose of the thesis has been to answer some of these complex questions; What are the benefits of using a simulation tool? In what way can we use it? If we choose to use a simulation tool, in what way does it affect our way of planning an assembly line? What are the advantages and disadvantages? Are there any economical and social aspects? Our results made us realize that a digital simulation tool does not replace the card board. On the other hand simulation could be used as a complement. Card board exercises and simulations play two different roles in the development of an assembly line. The use of card board is an excellent example of how you can generate a wide range of creative solutions at an early stage of the design process. This offers the possibility to create and evaluate several different concepts during a short period of time. We believe that the benefits of a simulation tool come in handy at a later stage of the design process, when a conceptual solution is selected. The simulation tool will be able to evaluate the solution and identify where problems may occur. The output of the simulation tool may also be used as a communication tool, internally as well as externally.

Development of Industrial robots is becoming more expensive and time consuming over the years. A lot of costs are spent in the development, and so it is necessary to improve the conceptual design phase. This thesis is an object lesson that shows one of the multiple ways to improve the named phase. It basically consists on, using a CAD program, build a robot whose parameters have to be modified from a user interface. The parameters to change are the dimensions of the robot’s parts (morphology parameterization) and also the parts to use (topology parameterization), which can be chosen from a large library of different parts. Some parameters are changed so as the build robot has similar mass properties to a given one, in order to be able to do some tests with it and export the results to improve the real robot. For this reason, in the interface done there is also written some code to get the mass properties of the built robot. Even so, this thesis only shows how to do the named actions but it has not been done any kind of test.

Hexplorer is a six-legged walking robot developed at the University of Waterloo. The robot is controlled by a network of seven digital signal processors, six of which control three motors each, for a total of 18 motors. Brand new custom electronics were designed to house the digital signal processors and associated circuitry. A variable duty factor wave gait, developed by Yoneda et al. was simulated and implemented on the robot. Simulation required an in-depth kinematic analysis that was complicated by the mechanical design of parallel mechanism comprising the legs. These complications were handled in both simulation and implementation. However, due to mechanical issues Hexplorer walked for only one or two steps at a time.

This thesis presents a detailed design, calibration, and control of a modular and reconfigurable robot (MRR) system. A MRR system not only includes modular mechanical hardware, but also modular electrical hardware, control algorithms and software. Also, those modular components can be easily constructed into various manipulator configurations to accomplish a wider range of tasks. MRRs represent the next generation of industrial manipulators that cope with the transition from mass to customer-oriented production. The main contributions of this thesis are: 1) mechanical design and calibration of multi-input multi-output (MIMO) joint modules of MRR, and 2) control design to handle multiple configuration and overcome disturbance due to dynamics uncertainty. From the mechanical design point of view, this thesis presents two main topics: 1) each joint is not only modularly designed, but also has multiple-input multiple-output (MIMO) physical connection ports, which contributes to the concept of reconfigurability. Strictly speaking, single-input single-output (SISO) modular joint falls into the category of modular manipulator, and the robot reconfiguration is achieved by integrating different types of modules. For example, with single revolute MIMO joint module, both rotary and pivotal joint can be generated. On the other hand, if you would like to switch from rotary movement to pivotal movement with a SISO joint module, using another pivotal joint module is the only way to achieve this goal, and 2) for precise automation application, joints and links should be accurately connected and oriented when reconfigured. Our proposed modular joint has four connection ports which can be configured as either a rotary joint or a pivotal joint. In addition, key and keyway connection mechanism provides high accuracy in positioning the link onto the joint. Therefore, this structure reduces or eliminates MRRs system calibration time when reconfigured. Furthermore, zero link offset when used as a pivotal joint increases the robot dexterity, maximizes the reachability, and results in kinematics simplicity. The main challenge in the control of an MRR system with harmonic drives (HD) is the significant uncertainties due to friction, unmodelled dynamics, varying payload, gravitation, dynamic coupling between motions of joints, and the configuration changes. In order to compensate all unpredictable effects, we proposed a decentralized saturation-type robust control scheme based on direct-Lyapunov method and backstepping techniques. To better understand the system dynamics behavior, the HD flexspline compliance and friction calibration and results are also provided. The results are used for controller design. The proposed controller is verified through both computer simulation and experimental analysis.