'The optics we're designing need to see as far as they can,' said Kristy Dalzell, Raytheon ELCAN optical designer. In high precision optical systems, even a few tiny microns can make an enormous difference.
Five microns is about 1/20th the thickness of a sheet of paper. That's why the company invests in partnerships and in research and development to improve the precision of its optical systems so that it can help customers see better and farther, even from miles above the Earth.Ī common unit of measurement in optics is the micron - one millionth of a meter. Raytheon ELCAN know that microns matter when it comes to their optical systems. We call this troubleshooting process 'chasing microns.'' 'No, we have to follow a pretty rigorous process of elimination of what we think could be moving, what could be out of alignment, and then troubleshoot from there. That's what moved,'' said Anthony De Aguiar, mechanical designer at Raytheon ELCAN. 'It's not like we can look at the system and say, 'Oh, there's your 20 microns right there. The company doesn't get a second chance to get it right. From optics for aircraft head-up displays to missile seekers and satellites, this alignment is critical for performance. This level of precision is important in everything the company does. So say we are looking through a telescope, which may have nine or 10 elements inside it, if some of those are not centered correctly, it's not going to work properly.' As you get into precision optics, you need to make sure the optical axis, which is like an imaginary line right through the middle of the system, is as perfect to the center as possible. 'You want your eye to look through the center of that lens. 'If you were to take a pair of glasses and shift them about an inch sideways either way, you're going to get distortions,' said Tony Brinovec, program manager for space at Raytheon ELCAN, a Raytheon Technologies subsidiary. Shuttle astronauts fixed the problem with a corrective optic in 1993. All rights reserved.Being just barely a hair off is nowhere near good enough when it comes to precision optics.Īn aberration - only 1/25th as broad as a human hair, caused during production - prevented the Hubble telescope from delivering razor-sharp imagery to NASA.
In sum, the overall results show that the OST-AR tool proposed can complement the conventional training of CVC.Ĭentral venous catheterization Medical training Needle placement Optical see-through augmented reality Professional assessment.Ĭopyright © 2020 Elsevier Ltd. Integration with ultrasound information was highlighted as necessary future work.
13 agreed that OST-AR adoption in these scenarios is likely, particularly during early stages of training. Finally, the result of semi-structured interviews with these 18 participants revealed that 14 of them considered that PIÑATA can complement the conventional training system, especially due to the visibility of the vessels inside the simulator. The qualitative answers of the participants also suggest its face and content validity, a high acceptability rate and a medium perceived workload. An inherent difference in the task completion time (p =0.040) and in the number of errors (p = 0.036) between novices and experts proved the construct validity of the new tool. A correlation was found between the task completion time in the two training methods, suggesting the concurrent validity of our OST-AR tool. The performance was objectively measured by task completion time and number of needle insertion errors. This was followed by a comparative study with 18 participants - attending specialists and medical residents - that performed needle insertion tasks for CVC with PIÑATAand the conventional training system. Our design contribution also describes the observation and co-design sessions used to collect user requirements, usability aspects and user preferences. In this work we introduce PIÑATA, an interactive tool to explore the benefits of OST-AR in CVC training using a dummy of the upper torso and neck andexplore if PIÑATA complements conventional training practices. However, limited research has been conducted on Optical See-Through Augmented Reality (OST-AR) interfaces for training needle insertion, especially for central venous catheterization (CVC).
These dummies offer an interesting space to augment with useful information to assist training practices, namely, internal anatomical structures (subclavian artery and vein, internal jugular vein and carotid artery) along with target point, desired inclination, position and orientation of the needle. Conventional needle insertion training relies on medical dummies that simulate surface anatomy and internal structures such as veins or arteries.