Thermal Robotic Arm Controlled Spraying via Robotic Arm and Vision System

The Tribology Surface Engineering industry is a worldwide multi billion euro industry with significant health and safety risks. The thermal spraying sector of this industry employs the technique of applying molten surface coating material to a substrate via a thermal spray process which is implemented either by manual spraying or pre-programmed robotic systems. The development of autonomous robotic systems for thermal spraying surface coating would significantly improve production and profitability over pre-programmed systems and improve health and safety over manual spraying. The aim of this research was to investigate and develop through software simulation, physical modelling and testing the development of robotic subsystems that are required to provide autonomous robotic control for the thermal spraying process. Computer based modelling programs were developed to investigate the control strategy identified for the thermal spaying process. The algorithms included fifth order polynomial trajectories and the complete dynamic model where gravitational, inertia, centrifugal and coriolis torques are considered. Tests provide detail of the load torques that must be driven by the robot electric actuator for various structural changes to the thermal spraying robot and for variations in trajectory boundary conditions during thermal spraying. The non-linear and coupled forward and inverse kinematic equations of a five axis articulated robot with continuous rotation joints were developed and tested via computer based modelling and miniature physical robot modelling. Both the computer based modelling and physical model confirmed the closed form kinematic solutions. A solution to running cables through the continuous rotation joints for power and data is present which uses polytetrafloraethylene (PTFE) electroless nickel. This material was identified during the literature review of surface coating materials. It has excellent wear, friction and conductivity properties. Physical tests on a slip ring and brushes test rig using electroless nickel are presented which confirm the viability of using PTFE electroless nickel as a slip ring. Measurement of the substrate during thermal spraying so as to autonomously control the thermal spaying robot is a significant challenge. This research presents solutions for the measurement of the substrate using a low cost camera system and lasers in a single wavelength environment. Tests were carried out which resulted in the removal of a butane flame obscuring a test piece requiring measurement from the camera image so that substrate measurements can be made using image processing and analysis techniques such as canny edge detection and centroid measurements. Test results for the low cost vision system provide depth measure errors of ±0.6 % and structural measurements such as area and perimeter in the range -5% to -7.5%. These results confirm the efficacy of this novel flame removal technique

New concepts in automation and robotic technology for surface engineering

Nowadays, the use of robots for the automation of process is very common. This is due to the advantages provided: cost reduction, quality increase, high reproducibility, etc. Nevertheless the robots have the disadvantage, that a high initial investment is necessary. Thermal spraying processes use industrial robots for many reasons, some of them are: high control of the process, quality increase, dangerous work environment, etc. The industrial robot can control many parameters during the process; like the trajectory and the velocity of the torch, which have a significant influence on the heat and mass transfer to the piece and coating. Properties such as coating thickness, porosity, micro hardness and thermal stress distribution are therefore significantly influenced by the spraying distance, velocity and trajectory. It is thus necessary to implement new tools, which support robot programming and fulfill the requirements of torch handling for thermal spraying and lacquered operation. Optimized robot programming is necessary for high quality products regarding coating properties and functionality. To optimize the robot programming, different off-line programming tools are used. The off-line programming has the advantages: increase of work safety and efficiency, low time to program, continuous production, etc.Escuela Técnica Superior de Ingeniería IndustrialUniversidad Politécnica de CartagenaInstitute for Manufacturing Technologies of Ceramic Components and Composites (IMTCCC; University of Stuttgart

Insight into the Design of Aerosol Spray Systems for Cell Therapies for Retinal Diseases using Computational Modelling and Experimental Assessment

Retinal degenerative diseases affect numerous people worldwide and in the UK; they lead to dysfunction of retinal cells and retinal dysfunction, in turn leading to vision loss and in some cases blindness. Existing treatments aim to alleviate current risk factors leading to retinal degeneration, such as increased high pressure. However, these procedures do not restore lost cell, vision nor retinal function, and therefore may still lead to blindness. Developing cell-based therapies to replace lost cells provides one option for retinal tissue repair in order to restore retinal function. These therapies involve delivering stem cells to encourage neural cell-like functions within the retinal tissue. Despite progress in developing stem-cells compatible with the retinal layers, there is also a need to developing a minimal invasive technique for cell delivery, without damaging the neighbouring optical structure. After evaluating several methods of cell delivery, this thesis explores the need for developing aerosol spraying systems for stem-cell delivery into the human eye. Mathematical modelling is used as a tool to define spraying parameters which, alongside experimental work, may accelerate the design of aerosol spraying systems to treat retinal degenerative disease such as glaucoma. Firstly, an organic biomaterial is developed and used as scaffold to spray and protect cells from aerodynamic forces and stresses associated with aerosolization. The rheological properties of this biomaterial are incorporated within a computational model to predict cell-spraying into a human eye. Boundary and initial conditions mimic the experimental spraying conditions, and the parameterised model is used to explore the link between operator-defined conditions (namely volume flow rate of the cell-laden hydrogel, external pressure needed for aerosolization and angle of the spraying) and spraying outputs (surface area of the retina covered, droplets speed, wall shear stress on the retinal surface). Data from both computational and experimental analyses were gathered. Computational modelling is used to explore the impact of spraying parameters (pressure and volume flow rate at the injector nozzle, outer cone angle for the spray) on key outputs of high priority, namely the spatial distribution of the delivered hydrogel on the retinal wall, the surface area of the retina covered and droplet speed. Droplets speed at the retinal wall appeared to increase with increasing pressure conditions and were observed at a constant volume flow rate. Experimental assessments were used to validate the computational data and determine cell viability under set environmental conditions (external pressure and volume flow rate of cell-laden hydrogel) through in-vitro testing. This thesis defines indicative spraying parameters for delivering therapeutic cells to the human retina, based on a combination of computational modelling and experimental studies. Mathematical modelling provides the potential to transfer these findings to other organ systems, aligning with broader effects to develop cell delivery systems to treat organ disease and repair

NASA Tech Briefs, September 1990

Topics covered include: New Product Ideas; NASA TU Services; Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Computer Programs; Mechanics; Machinery; Fabrication Technology; Mathematics and Information Sciences; Life Sciences

Technology 2000, volume 1

The purpose of the conference was to increase awareness of existing NASA developed technologies that are available for immediate use in the development of new products and processes, and to lay the groundwork for the effective utilization of emerging technologies. There were sessions on the following: Computer technology and software engineering; Human factors engineering and life sciences; Information and data management; Material sciences; Manufacturing and fabrication technology; Power, energy, and control systems; Robotics; Sensors and measurement technology; Artificial intelligence; Environmental technology; Optics and communications; and Superconductivity

Marshall Space Flight Center Research and Technology Report 2019

Today, our calling to explore is greater than ever before, and here at Marshall Space Flight Centerwe make human deep space exploration possible. A key goal for Artemis is demonstrating and perfecting capabilities on the Moon for technologies needed for humans to get to Mars. This years report features 10 of the Agencys 16 Technology Areas, and I am proud of Marshalls role in creating solutions for so many of these daunting technical challenges. Many of these projects will lead to sustainable in-space architecture for human space exploration that will allow us to travel to the Moon, on to Mars, and beyond. Others are developing new scientific instruments capable of providing an unprecedented glimpse into our universe. NASA has led the charge in space exploration for more than six decades, and through the Artemis program we will help build on our work in low Earth orbit and pave the way to the Moon and Mars. At Marshall, we leverage the skills and interest of the international community to conduct scientific research, develop and demonstrate technology, and train international crews to operate further from Earth for longer periods of time than ever before first at the lunar surface, then on to our next giant leap, human exploration of Mars. While each project in this report seeks to advance new technology and challenge conventions, it is important to recognize the diversity of activities and people supporting our mission. This report not only showcases the Centers capabilities and our partnerships, it also highlights the progress our people have achieved in the past year. These scientists, researchers and innovators are why Marshall and NASA will continue to be a leader in innovation, exploration, and discovery for years to come