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Soft robotics is an emerging research subject showing great promise for applications where traditional and rigid robotics is limited, for example, creating stroking sensation by using soft robotics. The purpose of this master's thesis project is to convey caress by designing and manufacturing a wearable haptic soft belt with locomotion. This device is mainly composed of pneumatic artificial muscles, pressurized actuator and control loop by Arduino. The locomotion of this device is realized through the elongation, shortening and position change of tubular pneumatic artificial muscles which was inspired by inchworm locomotion. Several different methods and materials were tested in the experiment. The results show that the device based on the principle of different friction successfully realizes the expected function.

An experimental program has been undertaken to gain a more fundamental understanding of dense-phase pneumatic transport of cohesionless solids. A 50.8 mm internal diameter circulating unit with both horizontal and vertical sections has been constructed . The pipe material is transparent lexan which allows for visual observation of the flow pattern. The particles used were a mixture of 95% white and 5% black polyethylene granules (particle diameter approximately 3 mm). The black particles were used to aid the visual observation of the flow pattern. The flow patterns ranged from dilute-phase flow to dense-phase plug flow. High-speed photographic techniques have been used to document the flow patterns in both the horizontal and vertical sections. Pressure drop measurements across a 70 cm test section have been coordinated with the film work. At the higher superficial air velocities (approximately 15 m/sec), the particles flow in a dilute suspension within the air stream. The pressure drop across the 70 cm section fluctuates very rapidly. For the horizontal dilute-phase flow, the mean pressure drop is approximately 0.12 kPa with fluctuations ranging from 0 to 0.3 kPa. For the vertical dilute-phase flow, the mean pressure drop is approximately 0.25 kPa with fluctuations ranging from 0 to 0.5 kPa. Upon reducing the superficial air velocity to 6.8 m/sec, the flow pattern in the horizontal section changes to a type of strand flow. The particles are conveyed in a dilute phase above a stationary layer. Large peaks in the pressure drop data (approximately 1 to 2 kPa) correspond to increases in the dilute-phase solids concentration. At the lower superficial air velocities (below 5 m/sec) , the solids flow pattern changes to dense-phase flow. The particles move in the form of plugs that occupy the entire pipe cross-section. For the horizontal flow, the plug length ranged from 0.17 to 0.60 m and the pressure drop across the plugs ranged from 1 to 5.2 kPa. The pressure gradient range can be predicted from the equations of Konrad et al. (1980). The analysis of the vertical dense-phase flow films is not as straightforward as the horizontal films. However, the flow pattern resembles that described by Konrad (1987) and there is qualitative agreement with the concepts outlined by Konrad (1987). / Master of Science

Yes / The fluidized bed coating system is a conventional process of particles coating in various industries. In this work, an experimental investigation was conducted using Response Surface Methodology (RSM) to optimize the coating mass of particles in a top-spray fluidized bed coating. The design of experiments (DOEs) is a useful tool for controlling and optimization of products in industry. Thus, DOE was conducted using MINITAB software, version 16. This process used a sodium silicate solution for coating the sodium percarbonate particles. The effect of the fluidization air flow rate, atomization air flow rate and liquid flow rate on the coating mass in the top-spray fluidized bed coating was investigated. The experimental results indicated that the coating mass of particles is directly proportional to the liquid flow rate of the coating solution and inversely proportional to the air flow rate. It was demonstrated that the flow rate of the coating solution had the greatest influence on the coating efficiency. / Metallic Material Processing Research Group, ACECR, Branch of Tehran University, Tehran, Iran.

This research examines different techniques and proposes a Computational Fluid Dynamics (CFD) model as a robust tool for flow characterization of load leveling valves. The load leveling valve is a critical component of an air suspension system since it manages air spring pressure, a key function that directly impacts vehicle dynamic performance in addition to maintaining a static ride height. Efficiency of operation of a load leveling valve is established by its flow characteristics, a metric useful in determining suitability of the valve for application in a truck-suspension configuration and for comparison among similar products. The disk-slot type load leveling valve was chosen as the subject of this study due to its popularity in the heavy truck industry. Three distinct methods are presented to model and evaluate flow characteristics of a disk-slot valve. First is a theoretical formulation based on gas dynamic behavior through an orifice; second is an experimental technique in which a full pneumatic apparatus is used to collect instantaneous pressure data to estimate air discharge; and third is a CFD approach. Significant discrepancies observed between theoretically estimated results and experimental data suggest that the theoretical model is incapable of accurately capturing losses that occur during air flow. These variations diminish as the magnitude of discharge coefficient is altered. A detailed CFD model is submitted as an effective tool for load leveling valve flow characterization/analysis. This model overcomes the deficiencies of the theoretical model and improves the accuracy of simulations. A 2-D axisymmetric approximation of the real fluid domain is analyzed for flow characteristics using a Realizable k-ϵ turbulence model, scalable wall functions, and a pressure-based coupled algorithm with a second order discretization function. The CFD-generated results were observed to be in agreement with the experimental findings. CFD is found to be advantageous in the evaluation of flow characteristics as it furnishes precise data without the need to experimentally evaluate a physical model/prototype of the valve, thereby benefitting suspension engineers involved in the development and testing of load leveling valve designs. This document concludes with a sample case study which uses CFD to characterize flow in a modified disk-slot load leveling valve, and discusses the results in light of application on a heavy truck. / MS / A majority of heavy trucks in North America equipped with air suspensions use a device known as a load leveling valve. This is a mechanical control system which manages pressure in air springs to maintain a preset/constant static ride height irrespective of the payload, doing so by sensing the distance between the truck frame and the axle. The rate of airflow to/from air springs in response to a road disturbance or load shift is critical to the stability of the truck when on the road. This rate of airflow for a given set of conditions constitutes flow characteristics of a load leveling valve. Accurate measurement of flow characteristics is necessary to understand the actual effect of the use of a particular valve on a truck-suspension configuration. This research addresses that requirement by presenting three distinct methods to model and evaluate flow characteristics of a load leveling valve, conducted on the disk-slot valve for its popularity in the heavy truck industry. First is a theoretical formulation based on flow of gas through an orifice; second is an experimental technique in which a full pneumatic apparatus is used to collect instantaneous pressure data to estimate air discharge; and third is a Computational Fluid Dynamics (CFD) approach. Significant discrepancies observed between theoretically estimated results and experimental data suggest that the theoretical model is incapable of accurately capturing losses that occur during air flow. The disparities also justify the adoption of CFD as an alternate method. A comprehensive CFD model is proposed as a capable tool for load leveling valve flow analysis/characterization. This model overcomes the deficiencies of the theoretical model and improves the accuracy of simulations. CFD-generated results are found to be in agreement with the experimental findings, highlighting its effectiveness at flow characterization. The ability of a CFD model to furnish precise data without the need to experimentally evaluate a physical model/prototype of the valve promises to benefit suspension engineers involved in the development and testing of load leveling valve designs. This document concludes with a sample case study which uses CFD to characterize flow in a modified disk-slot valve, and discusses the results in light of application on a heavy truck.

The thesis deals with the design of automated testing equipment of selected types of pneumatic valves. The problem of manual control process is its inefficiency, both in terms of human error rate and time loss caused by further assembly. The automated manual inspection process eliminates the problem. In the theoretical part, the types of switchgear are described, selected measuring procedures and methods of measurement are described. In the practical part, the measuring procedure was set out and on the basis of it there were designed variants of the testing machine and test circuit. The conclusion of the thesis contains evaluation of the whole project.

This diploma thesis deals with the design of test equipment for selected types of pneumatic cylinders. In the first, theoretical, part of the work is an analysis of the current state of knowledge in the field of pneumatic cylinders. Furthermore, the problems in the field of measurement and testing of pneumatic components are described here, selected linear position sensors are also described herein too. The second, practical, part deals with the choice of a suitable design variant and the actual solution of the test equipment design. A pneumatic circuit is also designed here. Part of the work is a 3D model of the test equipment and drawing documentation. The conclusion of the work is devoted to the overall evaluation of the work and recommendations for practice.

his thesis presents the design, fabrication, and testing of a robotic arm that is inherently safe, lightweight and affordable. The arm’s three joints are driven by novel hybrid vacuum-electric actuators that each combine origami-inspired soft pneumatic actuators (OSPAs) with a DC motor. The arm is a type of collaborative robot, or cobot, that is suitable for low payload, low speed applications. The OSPA was redesigned in the first stage of the research. In particular, the new endcaps are 59% shorter than the previous design. This made the actuators more compact and increased their stroke-to-length ratio. Next, the OSPA fabrication process was significantly changed. The heating of the heat shrink tubing was changed from immersion in boiling water to heating with a heat gun, and a motorized stand with several assisting parts was developed. These changes improved the consistency of the fabrication, reduced the skills required, and improved the safety. The joints of the arm and its structural components were designed next. The rotation of each joint is achieved by connecting multiple OSPAs to custom-made pulleys using cables and connecting a DC motor in parallel using a timing belt. Joint 2, the shoulder joint, had to produce the largest torque. This was accomplished by applying optimization methods to design a variable-radius pulley. The prototype arm utilized laser-cut acrylic and 3D printed components to keep its cost and weight low. Finally, after a simple pressure control system was developed, the prototype arm’s performance was extensively tested. The joints’ ranges of motion, velocities, accelerations, and blocked torques are tested at multiple pressures and motor currents, and the results discussed. The thesis concludes with a summary of the research’s achievements and limitations, and recommendations for future improvements to the robotic arm’s design. / Thesis / Master of Applied Science (MASc) / This thesis presents the design, fabrication, and testing of a robotic arm that is inherently safe, lightweight and affordable. The arm’s three joints are driven by novel actuators that each combine soft pneumatic actuators (powered by vacuum pressure) with a DC motor. The arm is suitable for low payload, low speed applications. First, the pneumatic actuators were redesigned to make them more compact. Next, their fabrication process was changed to improve the consistency of the results, reduce the skills required, and improve the safety. The joints of the arm and its structural components were then designed. To produce the torque required for the shoulder joint, optimization methods were used to create a variable-radius pulley. The prototype arm utilized laser-cut acrylic and 3D-printed components to keep its cost and weight low. Finally, after a simple pressure control system was developed, the prototype arm’s performance was extensively tested.

The Compact Rescue Crawler is a pneumatic legged robot. Two legs of a hexapod were designed and built. The legs are controlled directly from operator inputs. The operator gives foot position inputs through two PHANToM haptic controllers. A PD controller with a supplementary force gain-scheduler control stroke lengths of each cylinder. The force-based position control technique allows the robot feet to track operator inputs to within 10% position error. A guided gait algorithm was developed to allow the operator to control all 6 legs simply by haptically guiding the front two. The operator records successful and collision-free trajectories and the gait coordinator plays the trajectories through the rear legs as they approach the detected obstacles. This hybrid gait algorithm allows the robot to proceed through a hazardous environment, guided by an operator, but without taxing the input capabilities of the human operator.

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