Engineering as a profession faces the challenge of making the use of technology ubiquitous and transparent in society while at the same time raising young learners' interest and understanding of how technology works. Educational efforts in science, technology, engineering, and mathematics (i.e., STEM disciplines) continue to grow in pre-kindergarten through 12th grade (P-12) as part of addressing this challenge. This article explores how engineering education can support acquisition of a wide range of knowledge and skills associated with comprehending and using STEM knowledge to accomplish real world problem solving through design, troubleshooting, and analysis activities. We present several promising instructional models for teaching engineering in P-12 classrooms as examples of how engineering can be integrated into the curriculum. While the introduction of engineering education into P-12 classrooms presents a number of opportunities for STEM learning, it also raises issues regarding teacher knowledge and professional development, and institutional challenges such as curricular standards and high-stakes assessments. These issues are considered briefly with respect to providing direction for future research and development on engineering in P-12.

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A soft robotic gripper for a Tele-operable In-Home Robotic Assistant (TIHRA) for the mobility impaired is presented. This gripper is inspired by the Fin Ray ® Effect, which is derived from the physiology of fish fins. The gripper fingers are soft and triangular with hard crossbeams that buckle and deform in to conform around objects. The fingers of the TIHRA were altered from the original Fin Ray ® design in order to create a preferred bending direction, resulting in less force required to obtain a good grip on an object. The entire gripper can be 3D printed as part of a soft robotic hand made from hard and soft materials, and the motor-tendon actuation system attaches in a limited number of steps. Testing of the gripper included modeling the fingers and comparing grip strength them to the original Fin Ray ® to verify their optimization. Models show that the TIHRA fingers deform 15% more than traditional fingers when subjected to the same force. The TIHRA gripper was capable of holding 560 g, approximately 40% more than the gripper equipped with traditional fingers. This difference was statistically significant (p ≪ 0.001).The TIHRA hand was also tested at the 2016 RoboSoft Grand Challenge in Livorno, Italy. The gripper successfully completed some tasks, highlighting its conformability, deformability, and morphology, but performed poorly in others, demonstrating the need to increase the gripper strength to prevent out of plane twisting and bending and to increase the force that the gripper can exert. The gripper was attached to a Baxter robot to demonstrate its ability to interface with existing technology, and other versions of the gripper were designed and manufactured to show the scalability and versatility of the design.

This paper describes the result of both an experimental and an analytical investigation of the response of a two-dimensional, turbulent boundary layer in air to the presence of particles. Copper shot, 70 μm in diameter, were uniformly introduced into a vertical boundary layer, at a momentum thickness Reynolds number of about 1000. The particle mass flux was set at 20% of the fluid mass flux, and all measurements were made using a single-component, forward-scatter laser Doppler anemometer. The measurements clearly demonstrated that the particles damped fluid turbulence, apparently affecting all scales equally. The measurements further showed a strong correlation between the degree of damping and the particle concentration in the log region of the boundary layer.

Chemical mechanical planarization ͑CMP͒ is a process widely used for the manufacture of silicon integrated circuits. In this work, we measured the thickness of the slurry film between the wafer and the pad during polish while simultaneously measuring the frictional drag. All experiments are performed on a 1:2 scale laboratory tabletop rotary polisher with variable pad speed and wafer downforce control. Dual emission laser-induced fluorescence techniques optically measured the slurry film thickness through a dual-camera imaging system. The resulting data are discussed for wafers polished with a 3.1 wt % abrasive concentration slurry solution on Freudenberg's FX-9 polishing pads. It was found that the degree of surface curvature of the wafer substrate significantly influences the slurry film thickness and wafer drag, and therefore, the polish. The convex wafer shows the expected behavior of increased downforce reduces the slurry film thickness and increases the coefficient of friction. Further, as the pad speeds up, the slurry thickness increases and the friction decreases. The concave wafer shows no change in slurry film thickness and a decrease in the frictional coefficient with increasing downforce. Both the film thickness and frictional coefficient appear to decrease slightly with increasing pad speed. This difference between the two wafer shapes reflects the different fluid mechanics in each case.The chemical mechanical planarization ͑CMP͒ process is generally accepted as the technique used for the manufacture of integrated circuits ͑ICs͒, yet the understanding of the fundamental mechanisms involved in this process is limited. In recent years fundamental research has been done to both experimentally understand polishing characteristics and analytically model the processes involved. 1-3 To model the removal rate, one must first understand how the thin ͑ϳ20 m͒ film of slurry between the wafer and polishing pad behaves. Thin-film thicknesses also imply that the asperities in the pad reach through the slurry and rub on the pad. Wafer nonuniformities in turn lead to defects during production. Slurry film thickness during polishing is largely determined by how the hydrodynamic pressure of the fluid and the pad asperities support the wafer downforce. Levert, Mess, and Tichy have found that during polishing there is a vacuum created underneath a static wafer, pulling the wafer into the pad. 4-6 Sundararajan has found positive fluid pressure developing in the gap between the wafer and polishing pad. 7 In our experiments we witness both cases: positive pressure with a convex wafer ͑Fig. 1a͒ and negative pressure ͑vacuum͒ with a concave wafer ͑Fig. 1b͒. Frictional measurements during polishing help characterize the interaction between the wafer, abrasive ͑slurry͒, and pad. 8 This in turn helps identify the removal rate and its dependence on the lubrication regime. 3,[9][10][11][12] The separation distance between the polishing pad and the wafer substrate during CMP can be characterized by the thickness of the slurry laye...

Our goal in this article is to reflect on the role LEGO robotics has played in college engineering education over the last 15 years, starting with the introduction of the RCX in 1998 and ending with the introduction of the EV3 in 2013. By combining a modular computer programming language with a modular building platform, LEGO Education has allowed students (of all ages) to become active leaders in their own education as they build everything from animals for a robotic zoo to robots that play children's games. Most importantly, it allows all students to develop different solutions to the same problem to provide a learning community. We look first at how the recent developments in the learning sciences can help in promoting student learning in robotics. We then share four case studies of successful college-level implementations that build on these developments.

Since its introduction into integrated circuit (IC) manufacturing by IBM Corporation in the mid-1980s, chemical mechanical planarization (CMP) has become a key enabling technology in the semiconductor industry. All of the major IC manufacturers including Intel, Motorola, and IBM now incorporate CMP in the production of their chips. In addition to IC production, CMP applications have spread into other manufacturing processes including dynamic random access memory (DRAM) chips, hard drives, and modem chips.Given the magnitude of capital invested in this technology, there is a large impetus to develop a fundamental understanding of the process. Research with this goal in mind is being performed; however, an overall understanding of the process remains elusive because of the multidisciplinary nature of CMP. Researchers have focused on individual aspects of the process, such as slurry chemistry, 1-5 wafer-pad dynamics, 6-8 mechanisms, [9][10][11][12][13][14] and numerical simulations of the slurry fluid mechanics. [15][16][17] There has been, however, little experimental research regarding slurry fluid mechanics.Several researchers have commented on the importance of slurry flow and slurry distribution beneath the wafer although the importance of slurry flow has not been experimentally demonstrated. Stavreva et al. 18 discussed how the pad's ability to transport slurry could affect the polishing rate and uniformity during copper CMP. Parikh found that slurry flow rate had a large effect on the polishing uniformity on an orbital polisher. 19 Ali et al. 20 stated that the slurry composition, flow rate, and direction of slurry impingement onto the polishing pad all play important roles in interdielectric removal rates. Singer 21 reported that the manner in which slurry is transported from the outside of the wafer to its center is critically important. Sugimoto et al. 22 showed that slurry transport in grooved pads is important in reducing thermal gradients across a wafer. Since polishing rates are temperature dependent, a reduction in thermal gradients across the wafer is believed to reduce the within-wafer-nonuniformity. Ali et al. 23 postulated that the degradation in the removal rates of pads without conditioning is due to the decrease in the pad's slurry holding capacity. Liang et al. 24 postulated that Cabot's new open cell pads do not need macroscopic surface topography because of the pad's efficiency in channeling the slurry. Despite the fact that slurry flow generally is considered to be an important factor in the CMP process, there has not been an experimental study of the slurry flow or a numerical simulation sophisticated enough to examine the slurry behavior under realistic conditions. Slurry transport and mixing could influence the polishing performance in two ways: (i) transport of polished material and (ii) nonuniform slurry transport. The first mechanism was postulated by Cook in his research on glass polishing. 4 Cook suggested that polishing removal rate is influenced by the transport of polished materi...