Soft Pneumatic Fingertip Actuator Incorporating a Dual Air Chamber to Generate Multi-Mode Simultaneous Tactile Feedback

A complete set of diverse haptic feedbacks is essential for a highly realistic and immersive virtual environment. In this sense, a multi-mode haptic interface that simultaneously generates multiple kinds of haptic signals is highly desirable. In this paper, we propose a new silicone-made pneumatically controlled fingertip actuator to render pressure and vibrotactile feedback concurrently to offer a realistic and effective haptic sensation. A new silicone-based stacked dual-layer air chamber was designed. The volume of the chambers is controlled by pneumatic valves with compressed air tanks. The top/upper air chamber renders vibration feedback, whereas the bottom/lower air chamber renders pressure feedback. The proposed silicone-made fingertip actuator is designed so that it can be easily worn at the fingertips. To demonstrate the potential of the system, a virtual environment for rendering three different types of haptic textures was implemented. Extensive performance evaluation and user studies were carried out to demonstrate the proposed actuator’s effectiveness compared to an actuator with single vibrotactile feedback.

Sizing Directional Pneumatic Valves Based on the Characteristic Dynamic Behavior of Linear Actuators

In this paper, a novel approach to size directional pneumatic valves based on the analysis of the characteristic behavior of pneumatic actuators applied for pick and place tasks is presented. The study evidences the existence of three characteristic times in the displacement of a standard pneumatic actuation system, which are the emptying time, the transient-state time, and the steady-state time. The results also indicate that there is a close correlation between the velocity profile and the relative size of the piston area, where the steady-state time might be negligible when the piston is correctly sized. The emptying time, characterized by the depressurization of the counterpressure chamber, occurs predominantly with choked mass flow rate and constant volume. In this way, an analytical equation to estimate the emptying time has been determined. Moreover, during the transient-state time, the velocity profile is similar to the characteristic behavior of a first order system, therefore, the transient-state time is estimated by the time constant of the system, which was obtained by a linear first order model developed using the fundamental equations that govern the system behavior. The total displacement time, which is a design requirement to size directional valves, can be expressed as the sum of the emptying and transient-state time. Consequently, a set of equations are proposed to size the directional valve using design parameters such as displacement time, piston volume, load force, and supply pressure. The proposed equations were evaluated along with simulation and experimental results, demonstrating their validity and accuracy.

Integration of Ultra-Low Volume Pneumatic Microfluidics with a Three-Dimensional Electrode Network for On-Chip Biochemical Sensing

This paper reports a novel miniaturized pseudo reference electrode (RE) design for biasing Ion Sensitive Field Effect Transistors (ISFETs). It eliminates the need for post-CMOS processing and can scale up in numbers with the CMOS scaling. The presented design employs silane-mediated transfer of patterned gold electrode lines onto PDMS microfluidics such that the gold conformally coats the inside of microfluidic channel. Access to this electrode network is made possible by using “through-PDMS-vias” (TPV), which consist of high metal-coated SU-8 pillars manufactured by a novel process that employs a patterned positive resist layer as SU-8 adhesion depressor. When integrated with pneumatic valves, TPV and pseudo-RE network were able to bias 1.5 nanoliters (nL) of isolated electrolyte volumes. We present a detailed characterization of our pseudo-RE design demonstrating ISFET operation and its DC characterization. The stability of pseudo-RE is investigated by measuring open circuit potential (OCP) against a commercial Ag/AgCl reference electrode.

Under Pressure: Intractable Trade Conflicts and Korea – Pneumatic Valves

The Appellate Body (AB) report in Korea–Pneumatic Valves is among the most structurally complex of recent trade remedies reports. The AB weaves a complicated web to explicate the intricacies of the relationship among the relevant provisions on injury determination in anti-dumping disputes in the midst of a contentious and long-running series of disputes between two close regional trading powers. This Article first examines the Korean investigation and its significance in economic terms. Second, it analyzes the AB's conclusions on Article 6.2 of the Dispute Settlement Understanding regarding the panel request and the significance of the AB's treatment. Third, it studies the AB's comments on the panel's anti-dumping calculations where the AB amplifies its prior pronouncements on the elements of injury and causation. Finally, the Article situates this dispute in the broader political debates playing out both at the AB and between the two disputing parties.

SISTEM INVENTARISASI PENGGUNAAN PERALATAN DAN BAHAN PADA MEJA PRAKTIKUM PLC DI POLITEKNIK MANUFAKTUR NEGERI BANGKA BELITUNG MENGGUNAKAN BARCODE SCANNER

In the Programmable Logic Controller (PLC) course at Polmanbabel, students use a practicum table containing practicum equipment such as computer units, compressors, PLC units, pneumatic valves, sensors, jumper cables, etc. Before and after practicum, students are required to do an inventory of equipment and materials contained on this practicum desk. The inventory process is still done manually, where students write the name of the equipment, check the presence of the equipment, and calculate the amount. The thing that was complained by lecturers was the confiscation of practicum time as a result of the manual inventory process. Based on this, a new inventory system was created that uses the application and is equipped with a barcode scanner that is able to minimize the time and possibility of misplacement of the device. Based on the results of experiments, it can be seen that this system is able to minimize inventory time by an average of 14.65 minutes compared to manual inventory systems.

Calculation of brake-force distribution on three-axle agricultural trailers using simulation methods

The paper presents a new methodology for calculating the optimal linear distribution of braking forces for a three-axle trailer with "walking beam" and "bogie" suspension of the rear axle assembly that will meet the requirements of the new European legislation, EU Directive 2015/68. On this basis, a computer program for selecting the linear distribution of braking forces between axles has been developed. The presented calculations and simulation results of the braking process can be used in the design process to select the parameters of the wheel braking mechanisms and then the characteristics of the pneumatic valves of the braking system. The adaptation of the braking system of agriculture trailers is a very important factor for improving the safety of the transportation systems.