Dynamic 3D shape of the plantar surface of the foot using coded structured light:a technical report

The foot provides a crucial contribution to the balance and stability of the musculoskeletal system, and accurate foot measurements are important in applications such as designing custom insoles/footwear. With better understanding of the dynamic behavior of the foot, dynamic foot reconstruction techniques are surfacing as useful ways to properly measure the shape of the foot. This paper presents a novel design and implementation of a structured-light prototype system providing dense three dimensional (3D) measurements of the foot in motion. The input to the system is a video sequence of a foot during a single step; the output is a 3D reconstruction of the plantar surface of the foot for each frame of the input. Methods Engineering and clinical tests were carried out to test the accuracy and repeatability of the system. Accuracy experiments involved imaging a planar surface from different orientations and elevations and measuring the fitting errors of the data to a plane. Repeatability experiments were done using reconstructions from 27 different subjects, where for each one both right and left feet were reconstructed in static and dynamic conditions over two different days. Results The static accuracy of the system was found to be 0.3 mm with planar test objects. In tests with real feet, the system proved repeatable, with reconstruction differences between trials one week apart averaging 2.4 mm (static case) and 2.8 mm (dynamic case). Conclusion The results obtained in the experiments show positive accuracy and repeatability results when compared to current literature. The design also shows to be superior to the systems available in the literature in several factors. Further studies need to be done to quantify the reliability of the system in clinical environment

Intensive post-operative follow-up of breast cancer patients with tumour markers: CEA, TPA or CA15.3 vs MCA and MCA-CA15.3 vs CEA-TPA-CA15.3 panel in the early detection of distant metastases

BACKGROUND: In breast cancer current guidelines do not recommend the routine use of serum tumour markers. Differently, we observed that CEA-TPA-CA15.3 (carcinoembryonic (CEA) tissue polypeptide (TPA) and cancer associated 115D8/DF3 (CA15.3) antigens) panel permits early detection and treatment for most relapsing patients. As high sensitivity and specificity and different cut-off values have been reported for mucin-like carcinoma associated antigen (MCA), we compared MCA with the above mentioned tumour markers and MCA-CA15.3 with the CEA-TPA-CA15.3 panel. METHODS: In 289 breast cancer patients submitted to an intensive post-operative follow-up with tumour markers, we compared MCA (cut-off values, ≥ 11 and ≥ 15 U/mL) with CEA or CA15.3 or TPA for detection of relapse. In addition, we compared the MCA-CA15.3 and CEA-TPA-CA15.3 tumour marker panels. RESULTS: Distant metastases occurred 19 times in 18 (6.7%) of the 268 patients who were disease-free at the beginning of the study. MCA sensitivity with both cut-off values was higher than that of CEA or TPA or CA15.3 (68% vs 10%, 26%, 32% and 53% vs 16%, 42%, 32% respectively). With cut-off ≥ 11 U/mL, MCA showed the lowest specificity (42%); with cut-off ≥ 15 U/mL, MCA specificity was similar to TPA (73% vs 72%) and lower than that of CEA and CA15.3 (96% and 97% respectively). With ≥ 15 U/mL MCA cut-off, MCA sensitivity increased from 53% to 58% after its association with CA15.3. Sensitivity of CEA-TPA-CA15.3 panel was 74% (14 of 19 recurrences). Eight of the 14 recurrences early detected with CEA-TPA-CA15.3 presented as a single lesion (oligometastatic disease) (5) or were confined to bony skeleton (3) (26% and 16% respectively of the 19 relapses). With ≥ 11 U/mL MCA cut-off, MCA-CA15.3 association showed higher sensitivity but lower specificity, accuracy and positive predictive value than the CEA-TPA-CA15.3 panel. CONCLUSION: At both the evaluated cut-off values serum MCA sensitivity is higher than that of CEA, TPA or CA15.3 but its specificity is similar to or lower than that of TPA. Overall, CEA-TPA-CA15.3 panel is more accurate than MCA-CA15.3 association and can "early" detect a few relapsed patients with limited metastatic disease and more favourable prognosis. These findings further support the need for prospective randomised clinical trial to assess whether an intensive post-operative follow-up with an appropriate use of serum tumour markers can significantly improve clinical outcome of early detected relapsing patients

Control of Droplet Impact through Magnetic Actuation of Surface Microstructures

An effective method for on-demand control over the impact dynamics of droplets on a magnetoresponsive surface is reported. The surface is comprised of micrometer-sized lamellas from a magnetoactive elastomer on a copper substrate. The surface itself is fabricated using laser micromachining. The orientation of the lamellae is switched from edge-on (orthogonal to the surface) to face-on (parallel to the surface) by changing the direction of a moderate (< 250 mT) magnetic field. This simple actuation technique can significantly change the critical velocities of droplet rebound, deposition, and splashing. Rebound and deposition regimes can be switched up to Weber number We < 13±3, while deposition and splashing can be switched in the range of 32 < We < 52. Because a permanent magnet is used, no permanent power supply is required for maintaining the particular regime of droplet impact. The presented technology is highly flexible and enables selective fabrication and actuation of microstructures on complex devices. It has great potential for applications in soft robotics, microfluidics, and advanced thermal management. The following video files show typical water droplet impacts on different surfaces:•Droplet deposition on flat MAE at We = 10 (flat_We10.avi)•Droplet deposition on flat MAE at We = 44 (flat_We44.avi)•Droplet circular splash on flat MAE at We = 100 (flat_We100.avi)•Droplet deposition on “face on” MAE at We = 10 (side view: face_on_We10(side).avi, front view: face_on_We10(front).avi)•Droplet deposition on “face on” MAE at We = 44 (side view: face_on_We44(side).avi, front view: face_on_We44(front).avi)•Droplet parallel splash on “face on” MAE at We = 76 (side view: face_on_We76(side).avi, front view: face_on_We76(front).avi)•Droplet circular splash on “face on” MAE at We = 100 (side view: face_on_We100(side).avi, front view: face_on_We100(front).avi)•Droplet rebound on “edge on” MAE at We = 10 (side view: edge_on_We10(side).avi, front view: edge_on_We10(front).avi)•Droplet penetration on “edge on” MAE at We = 17 (side view: edge_on_We17(side).avi, front view: edge_on_We17(front).avi)•Droplet parallel splash on “edge on” MAE at We = 44 (side view: edge_on_We44(side).avi, front view: edge_on_We44(front).avi)•Droplet circular splash on “edge on” MAE at We = 172 (side view: edge_on_We172(side).avi, front view: edge_on_We172(front).avi

Control of Droplet Impact through Magnetic Actuation of Surface Microstructures

An effective method for on-demand control over the impact dynamics of droplets on a magnetoresponsive surface is reported. The surface is comprised of micrometer-sized lamellas from a magnetoactive elastomer on a copper substrate. The surface itself is fabricated using laser micromachining. The orientation of the lamellae is switched from edge-on (orthogonal to the surface) to face-on (parallel to the surface) by changing the direction of a moderate (< 250 mT) magnetic field. This simple actuation technique can significantly change the critical velocities of droplet rebound, deposition, and splashing. Rebound and deposition regimes can be switched up to Weber number We < 13±3, while deposition and splashing can be switched in the range of 32 < We < 52. Because a permanent magnet is used, no permanent power supply is required for maintaining the particular regime of droplet impact. The presented technology is highly flexible and enables selective fabrication and actuation of microstructures on complex devices. It has great potential for applications in soft robotics, microfluidics, and advanced thermal management. The following video files show typical water droplet impacts on different surfaces:•Droplet deposition on flat MAE at We = 10 (flat_We10.avi)•Droplet deposition on flat MAE at We = 44 (flat_We44.avi)•Droplet circular splash on flat MAE at We = 100 (flat_We100.avi)•Droplet deposition on “face on” MAE at We = 10 (side view: face_on_We10(side).avi, front view: face_on_We10(front).avi)•Droplet deposition on “face on” MAE at We = 44 (side view: face_on_We44(side).avi, front view: face_on_We44(front).avi)•Droplet parallel splash on “face on” MAE at We = 76 (side view: face_on_We76(side).avi, front view: face_on_We76(front).avi)•Droplet circular splash on “face on” MAE at We = 100 (side view: face_on_We100(side).avi, front view: face_on_We100(front).avi)•Droplet rebound on “edge on” MAE at We = 10 (side view: edge_on_We10(side).avi, front view: edge_on_We10(front).avi)•Droplet penetration on “edge on” MAE at We = 17 (side view: edge_on_We17(side).avi, front view: edge_on_We17(front).avi)•Droplet parallel splash on “edge on” MAE at We = 44 (side view: edge_on_We44(side).avi, front view: edge_on_We44(front).avi)•Droplet circular splash on “edge on” MAE at We = 172 (side view: edge_on_We172(side).avi, front view: edge_on_We172(front).avi)THIS DATASET IS ARCHIVED AT DANS/EASY, BUT NOT ACCESSIBLE HERE. TO VIEW A LIST OF FILES AND ACCESS THE FILES IN THIS DATASET CLICK ON THE DOI-LINK ABOV

Laser Micromachining of Magnetoactive Elastomers as Enabling Technology for Magneto-Responsive Surfaces

A simple method for structuring of the surface of a magnetoactive elastomer (MAE) on the tens of micrometers scale, which capabilities extend beyond conventional mold-based polymer casting, is reported. The method relies on the ablation of the material by absorption of nanosecond infrared pulses from a commercial laser. It is shown that it is possible to fabricate parallel lamellar structures with a high aspect ratio (up to 6 : 1) as well as structures with complex scanning trajectories. The method is fast (fabrication time for the 7 x 7 mm2 is about 60 s), and the results are highly reproducible. To illustrate the capabilities of the fabrication method, both orthogonal to the MAE surface and tilted lamellar structures are fabricated. These magnetosensitive lamellae can be easily bent by ±45° using an external magnetic field of about 230 mT. It is demonstrated that this bending allows one to control the sliding angle of water droplets in a great range between a sticky (>90°) and a sliding state (<20°). Perspectives on employing this fabrication technology for magneto-sensitive smart surfaces in microfluidic devices and soft robotics are discussed. DOI of article: 10.1002/admt.20210104

Combining Dynamic Foot Scanning and Additive Manufacturing for the Production of Insoles: a Case Study

This item is Closed Access.The development of an insole that is representative of the foot’s dynamic nature is crucial for good fit as well as comfort and performance. Additive manufacturing (AM) has the potential to allow the production of such insoles because of its tool-less capabilities and the ability to directly manufacture from CAD models at no extra cost. Research therefore has been undertaken to explore a process of foot capture by using a dynamic scanner for the design and manufacture of insoles using AM. The feet of four individuals were dynamically and statically scanned and from these data, four insole designs were developed for each person. The designs were: footprint, dynamic, average and static. The results indicated that the personalisation process is complex, mainly due to the need to identify and select the point cloud(s) from a large number of frames and manipulate them accordingly, presenting challenges in the design phase. The data from this study have demonstrated that combining dynamic scanning and AM technology is feasible for developing personalised insoles. While traditional footwear/insole is based on static data, this study can be considered as a starting point for the development of personalised insoles by using dynamic scanning and AM