This work was supported by the Wellcome Trust IEH Award [102431] and by the Wellcome/EPSRC Centre for Medical Engineering [WT203148/Z/16/Z]. The authors acknowledge financial support from the Department of Health via the National Institute for Health Research (NIHR) comprehensive Biomedical Research Centre award to Guy&#39;s &#38; St Thomas&#39; NHS Foundation Trust in partnership with King&#39;s College London and King&#39;s College Hospital NHS Foundation Trust.

1. Preparation of Each Link, End-effector, and Additional Components
<ol>
	<li>Print all the links (L0, L1, L2, L3, and L4) and the end-effector as shown in Figure 1, with acrylonitrile butadiene styrene (ABS) plastic, polylactic acid (PLA) plastic, or nylon, using a 3D-printing service. Use the .STL files provided in the Supplementary Materials when printing. 
	NOTE: Changes in shape and scale of each part can be made based on the provided files. The inner profile of the end-effector can be changed to fit different US probes.</li>
	<li>Print all the required additional components as shown in Figure 2 in nylon, using a 3D-printing service. Refer to the Table of Materials for the required number of each component. Use the .STL files provided in the Supplementary Materials when printing.</li>
	<li>Polish all the printed plastic parts with polishing tools if necessary. Remove any supporting materials left from 3D printing, if necessary. 
	NOTE: Some structures in the provided end-effector design are for a force sensor, which is not a part of the protocol reported here and will not be used for the assembly. The force sensor design concept has been reported in previous work20; thus, it is not covered in this paper.</li>
</ol>
2. Assembly of Joint 1
NOTE: The assembly of joint 1 (J1) is based on Figure 3.
<ol>
	<li>Place the four small, geared stepper motors (with 20-teeth spur gears attached) into the mounting cavities of L0 and mount them with screws.</li>
	<li>Place the two 37 mm OD bearings into the bearing housings of L0 and secure the 120-teeth spur gear (Type A) onto the hexagon key of L1.</li>
	<li>Insert the shaft on L1 into the shaft hole on L0 with the four small driving spur gears and the large, driven spur gear engaged, and assemble the shaft collar to secure and retain the shaft.</li>
</ol>
3. Assembly of Joint 2
NOTE: The assembly of joint 2 (J2) is based on Figure 4.
<ol>
	<li>Place the four small, geared stepper motors (with 20-teeth spur gears attached) into the mounting cavities of L1 and mount them with screws.</li>
	<li>Attach the two 120-teeth spur gears (Type B) to the two 37 mm OD bearings and position them into the gear cavities of L1, with the 120-teeth spur gear (Type B) engaged with the 20-teeth spur gears mounted on the motors.&#160;Unscrew and re-screw the motor if necessary to allow the easy positioning of the two 120-teeth type-B spur gear.</li>
	<li>Align L1 and L2 and insert the bearing and the ball-spring pairs into the clutch holes in L2. With the two round clutch covers aligning and pushing the spring into the clutch mechanism for preloading, insert an M6 bolt into the bores of L1 and L2.</li>
	<li>Rotate the assembly to the other side and repeat steps in 3.3 for this side. Secure the assembly by attaching a nut to the M6 bolt.</li>
</ol>
4. Assembly of Joint 3
NOTE: The assembly of joint 3 (J3) is based on Figure 5.
<ol>
	<li>Place the two small, geared stepper motors (with 20-teeth spur gears attached) into the mounting cavities of L2 and mount them with screws.</li>
	<li>Place the 37 mm OD bearing into the bearing housing of the 120-teeth spur gear (Type C) and place the 32 mm OD bearing into the bearing housing of L3.</li>
	<li>Secure the large spur gear into the hexagon keyhole of L3 (additional screws can be used if necessary) and insert the shaft on L2 into the bores on the large spur gear and L3, with the small and the large spur gears engaged.</li>
</ol>
5. Assembly of the Driving Mechanism of Joint 4
NOTE: The assembly of joint 4 (J4) is based on Figure 6.
<ol>
	<li>Place the two small, geared stepper motors into the mounting cavities of L3 and mount them with screws. Place the 8 mm OD bearings into the bearing housings of L4.</li>
	<li>Mount the 20-teeth long spur gear onto the two small stepper motors.</li>
</ol>
6. Assembly of the Driven Mechanism of Joint 4 and Joint 5
NOTE: The assembly of joint 4 (J4) is based on Figure 6 and joint 5 (J5) is based on Figure 7.
<ol>
	<li>Position the driven 144 teeth bevel gear onto the extrusion of L4.</li>
	<li>Place the two small, geared stepper motors (with 18-teeth bevel gears attached) into the mounting cavities of L4 and mount them with screws.&#160;Finally, insert the M5 shaft into the shaft hole of L3 and L4 after the two links are aligned. Ensure the built in driven gear structures on L4 matches with the 20 teeth long spur gear.</li>
	<li>Insert the end-effector into the keyway of the large bevel gear and vertically position the end-effector with the end-effector collar screwed onto it.&#160;</li>
</ol>

<ol><li>Priester, A. M., Natarajan, S., Culjat, M. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Robotic+ultrasound+systems+in+medicine%5BTitle%5D)+AND+%22IEEE+Transactions+on+Ultrasonics%2C+Ferroelectrics%2C+and+Frequency+Control%22%5BJournal%5D)">Robotic ultrasound systems in medicine.</a> IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control. 60 (3), 507-523 (2013).</li>
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<li>Georgescu, M., Sacccomandi, A., Baudron, B., Arbeille, P. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Remote+sonography+in+routine+clinical+practice+between+two+isolated+medical+centers+and+the+university+hospital+using+a+robotic+arm%3A+a+1-year+study%5BTitle%5D)+AND+%22Telemedicine+and+e-Health%22%5BJournal%5D)">Remote sonography in routine clinical practice between two isolated medical centers and the university hospital using a robotic arm: a 1-year study.</a> Telemedicine and e-Health. 22 (4), 276-281 (2016).</li>
<li>Arbeille, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Use+of+a+robotic+arm+to+perform+remote+abdominal+telesonography%5BTitle%5D)+AND+%22American+Journal+of+Roentgenology%22%5BJournal%5D)">Use of a robotic arm to perform remote abdominal telesonography.</a> American Journal of Roentgenology. 188 (4), W317-W322 (2007).</li>
<li>Arbeille, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Fetal+tele%E2%80%90echography+using+a+robotic+arm+and+a+satellite+link%5BTitle%5D)+AND+%22Ultrasound+in+Obstetrics+%26+Gynecology%22%5BJournal%5D)">Fetal tele‐echography using a robotic arm and a satellite link.</a> Ultrasound in Obstetrics & Gynecology. 26 (3), 221-226 (2005).</li>
<li>Vieyres, P., et al. A tele-operated robotic system for mobile tele-echography: The OTELO project. <a target="_blank" href="http://scholar.google.com/scholar?hl=en&safe=off&q=author%3aVieyres%2C+P+%22M-Health%3A+Emerging+Mobile+Health+Systems%22">M-Health: Emerging Mobile Health Systems</a>. Istepanian, R. H., Laxminarayan, S., Pattichis, C. S. , Boston, MA. 461-473 (2006).</li>
<li>Abolmaesumi, P., Salcudean, S. E., Zhu, W. H., Sirouspour, M. R., DiMaio, S. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Image-guided+control+of+a+robot+for+medical+ultrasound%5BTitle%5D)+AND+%22IEEE+Transactions+on+Robotics+and+Automation%22%5BJournal%5D)">Image-guided control of a robot for medical ultrasound.</a> IEEE Transactions on Robotics and Automation. 18 (1), 11-23 (2002).</li>
<li>Abolmaesumi, P., Salcudean, S., Zhu, W. Visual servoing for robot-assisted diagnostic ultrasound. <a target="_blank" href="http://scholar.google.com/scholar?hl=en&safe=off&q=author%3aAbolmaesumi%2C+P+%22Engineering+in+Medicine+and+Biology+Society%2C+Proceedings+of+the+22nd+Annual+International+Conference+of+the+IEEE%22">Engineering in Medicine and Biology Society, Proceedings of the 22nd Annual International Conference of the IEEE</a>. , Chicago, IL. (2000).</li>
<li>Menikou, G., Yiallouras, C., Yiannakou, M., Damianou, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((MRI%E2%80%90guided+focused+ultrasound+robotic+system+for+the+treatment+of+bone+cancer%5BTitle%5D)+AND+%22The+International+Journal+of+Medical+Robotics+and+Computer+Assisted+Surgery%22%5BJournal%5D)">MRI‐guided focused ultrasound robotic system for the treatment of bone cancer.</a> The International Journal of Medical Robotics and Computer Assisted Surgery. 13 (1), e1753(2017).</li>
<li>Yiallouras, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Three-axis+MR-conditional+robot+for+high-intensity+focused+ultrasound+for+treating+prostate+diseases+transrectally%5BTitle%5D)+AND+%22Journal+of+Therapeutic+Ultrasound%22%5BJournal%5D)">Three-axis MR-conditional robot for high-intensity focused ultrasound for treating prostate diseases transrectally.</a> Journal of Therapeutic Ultrasound. 3 (1), 2(2015).</li>
<li>AdEchoTech. MELODY, a remote, robotic ultrasound solution. , Available from:
 <a target="_blank" href="http://www.adechotech.com/products/">http://www.adechotech.com/products/</a> (2018).</li>
<li>Essomba, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((A+specific+performances+comparative+study+of+two+spherical+robots+for+tele-echography+application%5BTitle%5D)+AND+%22Proceedings+of+the+Institution+of+Mechanical+Engineers%2C+Part+C%3A+Journal+of+Mechanical+Engineering+Science%22%5BJournal%5D)">A specific performances comparative study of two spherical robots for tele-echography application.</a> Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science. 228 (18), 3419-3429 (2014).</li>
<li>Bassit, L. A. <a target="_blank" href="http://scholar.google.com/scholar?hl=en&safe=off&q=%22Structure+m%C3%A9canique+%C3%A0+modules+sph%C3%A9riques+optimis%C3%A9es+pour+un+robot+m%C3%A9dical+de+t%C3%A9l%C3%A9-%C3%A9chographie+mobile%22">Structure mécanique à modules sphériques optimisées pour un robot médical de télé-échographie mobile</a>. , Université d’Orléans. France. PhD thesis (2005).</li>
<li>Noh, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Multi-Axis+force%2Ftorque+sensor+based+on+Simply-Supported+beam+and+optoelectronics%5BTitle%5D)+AND+%22Sensors%22%5BJournal%5D)">Multi-Axis force/torque sensor based on Simply-Supported beam and optoelectronics.</a> Sensors. 16 (11), 1936(1936).</li>
<li>Noh, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((An+ergonomic+handheld+ultrasound+probe+providing+contact+forces+and+pose+information%5BTitle%5D)+AND+%22Engineering+in+Medicine+and+Biology+Society%2C+Proceedings+of+the+37th+Annual+International+Conference+of+the+IEEE%22%5BJournal%5D)">An ergonomic handheld ultrasound probe providing contact forces and pose information.</a> Engineering in Medicine and Biology Society, Proceedings of the 37th Annual International Conference of the IEEE. , Milan, Italy. (2015).</li>
<li>Maplesoft. Translational Detent – MapleSim Help. , Available from:
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</ol>

The authors have nothing to disclose.

Unlike many other industrial robots that have been translated into medical applications, the proposed robotic manipulator described in the protocol was specifically designed for US examinations according to clinical requirements for the range of motion, application of force, and safety management. The lightweight robotic manipulator itself has a wide range of movements sufficient for most extra-corporeal US scanning, without the need for large movements of the global positioning mechanism. As the closest mechanical struc...

An extra-corporeal robotic ultrasound (US) system refers to the configuration in which a robotic system is utilized to hold and manipulate a US probe for external examinations, including its use in cardiac, vascular, obstetric, and general abdominal imaging1. The use of such a robotic system is motivated by the challenges of manually holding and manipulating a US probe, for instance, the challenge of finding standard US views required by clinical imaging protocols and the risk of repetitive strain injury2,3,4, and also by the needs of US screening programs, for instance,&#160;the requirement for experienced sonographers to be on-site5,6. With emphases on different functionalities and target anatomies, several robotic US systems, as reviewed in earlier works1,7,8, have been introduced since the 1990s, to improve different aspects of US examination (e.g.,&#160;long-distance teleoperation9,10,11,12, as well as robot-operator interaction and automatic control)13,14. In addition to the robotic US systems used for diagnostic purposes, robotic high-intensity focused ultrasound (HIFU) systems for treatment purposes have been widely investigated as summarized by Priester et al.1, with some recent works15,16 reporting the latest progress.
Although several robotic US systems have been developed with relatively reliable technologies for control and clinical operation, only a few of them have been successfully translated into clinical use, such as a commercially available tele-ultrasound system17. One possible reason is the low level of acceptance for large-size industrial-looking robots working in a clinical environment, from the point of view of both patients and sonographers. Additionally, for safety management, the majority of the existing US robots rely on force sensors to monitor and control the applied pressure to the US probe, while more fundamental mechanical safety mechanisms to limit the force passively are usually not available. This may also cause concerns when translating into clinical use as the safety of robot operation would be purely dependent on electrical systems and software logic.
With the recent advancements of 3D printing techniques, specially shaped plastic links with custom-made joint mechanisms could provide a new opportunity for developing bespoke medical robots. Carefully designed lightweight components with a compact appearance could improve clinical acceptance. Specifically for US examination, a bespoke medical robot aimed at being translated into clinical use should be compact, with enough degrees of freedom (DOFs) and range of motion to cover the region of interest of a scan; for example, the abdominal surface, including both the top and sides of the belly. Additionally, the robot should also incorporate the ability to perform fine adjustments of the US probe in a local area, when trying to optimize a US view. This usually includes tilting movements of the probe within a certain range, as suggested by Essomba et al.18 and Bassit19. To further address the safety concerns, it is expected that the system should have passive mechanical safety features which are independent of electrical systems and software logic.
In this paper, we present the detailed design and assembly method of a 5-DOF dexterous robotic manipulator, which is used as the key component of an extra-corporeal robotic US system. The manipulator consists of several lightweight 3D-printable links, custom-made joint mechanisms, and a built-in safety clutch. The specific arrangement of the DOFs provides full flexibility for probe adjustments, allowing easy and safe operations in a small area without colliding with the patient. The proposed multi-DOF manipulator aims to work as the main component that is in contact with patients and it can be simply attached to any conventional 3-DOF global positioning mechanism to form a complete US robot with fully active DOFs to perform a US scan.

<table><tbody><tr><td>3D-printed link L&lt;sub&gt;0&lt;/sub&gt;</td><td>3D printing service</td><td>1</td><td>As shown in Figure 1, with the STL file provided</td></tr><tr><td>3D-printed link L&lt;sub&gt;1&lt;/sub&gt;</td><td>3D printing service</td><td>1</td><td>As shown in Figure 1, with the STL file provided</td></tr><tr><td>3D-printed link L&lt;sub&gt;2&lt;/sub&gt;</td><td>3D printing service</td><td>1</td><td>As shown in Figure 1, with the STL file provided</td></tr><tr><td>3D-printed link L&lt;sub&gt;3&lt;/sub&gt;</td><td>3D printing service</td><td>1</td><td>As shown in Figure 1, with the STL file provided</td></tr><tr><td>3D-printed link L&lt;sub&gt;4&lt;/sub&gt;</td><td>3D printing service</td><td>1</td><td>As shown in Figure 1, with the STL file provided</td></tr><tr><td>3D-printed end-effector</td><td>3D printing service</td><td>1</td><td>As shown in Figure 1, with the STL file provided</td></tr><tr><td>20-teeth spur gear</td><td>3D printing service</td><td>12</td><td>0.5 module, 5 mm face width, with mounting keyway, as shown in Figure 2, with the STL file provided</td></tr><tr><td>18-teeth bevel gear</td><td>3D printing service</td><td>2</td><td>0.5 module, 5 mm face width, with mounting keyway, as shown in Figure 2, with the STL file provided</td></tr><tr><td>120-teeth spur gear (Type A)</td><td>3D printing service</td><td>1</td><td>0.5 module, 6 mm face width, with mounting keyway, bearing housing, and bore, as shown in Figure 2, with the STL file provided</td></tr><tr><td>120-teeth spur gear (Type B)</td><td>3D printing service</td><td>2</td><td>0.5 module, 6 mm face width, with detent holes, bearing housing, and bore, as shown in Figure 2, with the STL file provided</td></tr><tr><td>120-teeth spur gear (Type C)</td><td>3D printing service</td><td>1</td><td>0.5 module, 6 mm face width, with mounting key, bearing housing, and bore, as shown in Figure 2, with the STL file provided</td></tr><tr><td>20-teeth long spur gear</td><td>3D printing service</td><td>1</td><td>0.5 module, 21.5 mm face width, with mounting keyways, as shown in Figure 2, with the STL file provided</td></tr><tr><td>144-teeth bevel gear</td><td>3D printing service</td><td>1</td><td>0.5 module, 7 mm face width, with mounting keyways, as shown in Figure 2, with the STL file provided</td></tr><tr><td>Bearing (37 mm O.D and 30 mm I.D)</td><td>Bearing Station Ltd., UK</td><td>5</td><td>Bearing size and supplier can be varied</td></tr><tr><td>Bearing (12 mm O.D and 6 mm I.D)</td><td>Bearing Station Ltd., UK</td><td>2</td><td>Bearing size and supplier can be varied</td></tr><tr><td>Bearing (32 mm O.D and 25 mm I.D)</td><td>Bearing Station Ltd., UK</td><td>1</td><td>Bearing size and supplier can be varied</td></tr><tr><td>Bearing (8 mm O.D and 5 mm I.D)</td><td>Bearing Station Ltd., UK</td><td>2</td><td>Bearing size and supplier can be varied</td></tr><tr><td>Plastic/metal shaft (6 mm O.D, 70 mm long)</td><td>TR Fastenings Ltd., UK</td><td>1</td><td>e.g. Could be an M6 bolt and a nut</td></tr><tr><td>Plastic/metal shaft (5 mm O.D, 70 mm long)</td><td>TR Fastenings Ltd., UK</td><td>1</td><td>e.g. Could be an M5 bolt and a nut</td></tr><tr><td>Ball-spring pairs</td><td>WDS Ltd., UK</td><td>4</td><td>Numbers of ball-spring pairs could varied to adjust the triggering force of the clutch</td></tr><tr><td>Clutch covers</td><td>3D printing service</td><td>2</td><td>104 mm O.D, 5mm face width, 6 mm bore, as shown in Figure 2, with the STL file provided</td></tr><tr><td>3D-printed shaft collar</td><td>3D printing service</td><td>1</td><td>35 mm O.D and 30 mm I.D, 8mm face width, as shown in Figure 2, with the STL file provided</td></tr><tr><td>3D-printed end-effector collar</td><td>3D printing service</td><td>1</td><td>As shown in Figure 2, with the STL file provided</td></tr><tr><td>Small geared stepper motors</td><td>AOLONG TECHNOLOGY Ltd., China</td><td>14</td><td>Part number: GM15BYS; Internal gear ratio 232:1 or 150:1, all acceptable</td></tr></tbody></table>

design and implementation of a bespoke robotic manipulator for extra-corporeal ultrasound

With the potential for high precision, dexterity, and repeatability, a self-tracked robotic system can be employed to assist the acquisition of real-time ultrasound. However, limited numbers of robots designed for extra-corporeal ultrasound have been successfully translated into clinical use. In this study, we aim to build a bespoke robotic manipulator for extra-corporeal ultrasound examination, which is lightweight and has a small footprint. The robot is formed by five specially shaped links and custom-made joint mechanisms for probe manipulation, to cover the necessary range of motion with redundant degrees of freedom to ensure the patient&#39;s safety. The mechanical safety is emphasized with a clutch mechanism, to limit the force applied to patients. As a result of the design, the total weight of the manipulator is less than 2 kg and the length of the manipulator is about 25 cm. The design has been implemented, and simulation, phantom, and volunteer studies have been performed, to validate the range of motion, the ability to make fine adjustments, mechanical reliability, and the safe operation of the clutch. This paper details the design and implementation of the bespoke robotic ultrasound manipulator, with the design and assembly methods illustrated. Testing results to demonstrate the design features and clinical experience of using the system are presented. It is concluded that the current proposed robotic manipulator meets the requirements as a bespoke system for extra-corporeal ultrasound examination and has great potential to be translated into clinical use.

Following the protocol, the resulting system is a robotic manipulator with five specially shaped links (L0 to L4) and five revolute joints (J1 to J5) for moving, holding, and locally tilting a US probe (Figure 8). The top rotation joint (J1), with gear mechanisms actuated by four motors, can rotate the following structures 360&#176;, to allow the US probe to point toward different sides of the scanning ar...

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Design and Implementation of a Bespoke Robotic Manipulator for Extra-corporeal Ultrasound

This paper introduces the design and implementation of a bespoke robotic manipulator for extra-corporeal ultrasound examination. The system has five degrees of freedom with lightweight joints made by 3D printing and a mechanical clutch for safety management.

With the potential for high precision, dexterity, and repeatability, a self-tracked robotic system can be employed to assist the acquisition of real-time ...

design-implementation-bespoke-robotic-manipulator-for-extra-corporeal

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9.1K Views.  King's College London. We ontwikkelden een spaakrobot manipulator extra lichamelijke echografie, die zal gericht zijn om te vertalen in klinisch gebruik. Het gebruik van robotsystemen voor ultrasone diagnose, kan mogelijk verbeteren medische diagnose. De manipulator bestaat uit loodgewicht, zodat de afdrukbare dingen, weg van kunststoffen die een mechanische koppeling, functie.De koppeling is onafhankelijk van elektrische systemen en suferal logica. De robotechografie manipulator kan worden gebruikt door Ste...

Video: Design and Implementation of a Bespoke Robotic Manipulator for Extra-corporeal Ultrasound

Design and Fabrication of an Elastomeric Unit for Soft Modular Robots in Minimally Invasive Surgery

In recent years, soft robotics technologies have aroused increasing interest in the medical field due to their intrinsically safe interaction in unstructured environments. At the same time, new procedures and techniques have been developed to reduce the invasiveness of surgical operations. Minimally Invasive Surgery (MIS) has been successfully employed for abdominal interventions, however standard MIS procedures are mainly based on rigid or semi-rigid tools that limit the dexterity of the clinician. This paper presents a soft and high dexterous manipulator for MIS. The manipulator was inspired by the biological capabilities of the octopus arm, and is designed with a modular approach. Each module presents the same functional characteristics, thus achieving high dexterity and versatility when more modules are integrated. The paper details the design, fabrication process and the materials necessary for the development of a single unit, which is fabricated by casting silicone inside specific molds. The result consists in an elastomeric cylinder including three flexible pneumatic actuators that enable elongation and omni-directional bending of the unit. An external braided sheath improves the motion of the module. In the center of each module a granular jamming-based mechanism varies the stiffness of the structure during the tasks. Tests demonstrate that the module is able to bend up to 120&#176; and to elongate up to 66% of the initial length. The module generates a maximum force of 47 N, and its stiffness can increase up to 36%.

This paper describes the design and fabrication of a soft unit for surgical manipulators. The base module includes three flexible fluidic actuators to achieve omnidirectional bending and elongation, and a granular jamming-based mechanism to enable stiffness control. A complete mechanical characterization is also reported.

In recent years, soft robotics technologies have aroused increasing interest in the medical field due to their intrinsically safe interaction in ...

Bioengineering

Rod-based Fabrication of Customizable Soft Robotic Pneumatic Gripper Devices for Delicate Tissue Manipulation

Soft compliant gripping is essential in delicate surgical manipulation for minimizing the risk of tissue grip damage caused by high stress concentrations at the point of contact. It can be achieved by complementing traditional rigid grippers with soft robotic pneumatic gripper devices. This manuscript describes a rod-based approach that combined both 3D-printing and a modified soft lithography technique to fabricate the soft pneumatic gripper. In brief, the pneumatic featureless mold with chamber component is 3D-printed and the rods were used to create the pneumatic channels that connect to the chamber. This protocol eliminates the risk of channels occluding during the sealing process and the need for external air source or related control circuit. The soft gripper consists of a chamber filled with air, and one or more gripper arms with a pneumatic channel in each arm connected to the chamber. The pneumatic channel is positioned close to the outer wall to create different stiffness in the gripper arm. Upon compression of the chamber which generates pressure on the pneumatic channel, the gripper arm will bend inward to form a close grip posture because the outer wall area is more compliant. The soft gripper can be inserted into a 3D-printed handling tool with two different control modes for chamber compression: manual gripper mode with a movable piston, and robotic gripper mode with a linear actuator. The double-arm gripper with two actuatable arms was able to pick up objects of sizes up to 2 mm and yet generate lower compressive forces as compared to elastomer-coated and non-coated rigid grippers. The feasibility of having other designs, such as single-arm or hook gripper, was also demonstrated, which further highlighted the customizability of the soft gripper device, and it's potential to be used in delicate surgical manipulation to reduce the risk of tissue grip damage.

This protocol describes a rod-based approach, combining 3D-printing and soft lithography techniques for fabricating the soft gripper devices. This approach eliminates the need for an external air source by incorporating a chamber component and reduces the chance of occlusion during the sealing process, particularly for miniaturized pneumatic channels.

Soft compliant gripping is essential in delicate surgical manipulation for minimizing the risk of tissue grip damage caused by high stress concentrations ...

A Teleoperated Robotic System-Assisted Percutaneous Transiliac-Transsacral Screw Fixation Technique

Transiliac-transsacral screw fixation is challenging in clinical practice as the screws need to break through six layers of cortical bone. Transiliac-transsacral screws provide a longer lever arm to withstand the perpendicular vertical shear forces. However, the screw channel is so long that a minor discrepancy can lead to iatrogenic neurovascular injuries. The development of medical robots has improved the precision of surgery. The present protocol describes how to use a new teleoperated robotic system to execute transiliac-transacral screw fixation. The Robot was operated remotely to position the entry point and adjust the orientation of the sleeve. The screw positions were evaluated using postoperative computed tomography (CT). All the screws were safely implanted, as confirmed using intraoperative fluoroscopy. Postoperative CT confirmed that all the screws were in the cancellous bone. This system combines the doctor's initiative with the Robot's stability. The remote control of this procedure is possible. Robot-assisted surgery has a higher position-retention capacity compared with conventional methods. In contrast to active robotic systems, surgeons have full control over the operation. The robot system is fully compatible with operating room systems and does not require additional equipment.

Teleoperated robotic system-assisted percutaneous transiliac-transsacral screw fixation is a feasible technique. Screw channels can be implemented with high accuracy owing to the excellent freedom of movement and stability of the robotic arms.

Transiliac-transsacral screw fixation is challenging in clinical practice as the screws need to break through six layers of cortical bone. ...

An Experimental Protocol for Assessing the Performance of New Ultrasound Probes Based on CMUT Technology in Application to Brain Imaging

The possibility to perform an early and repeatable assessment of imaging performance is fundamental in the design and development process of new ultrasound (US) probes. Particularly, a more realistic analysis with application-specific imaging targets can be extremely valuable to assess the expected performance of US probes in their potential clinical field of application.
The experimental protocol presented in this work was purposely designed to provide an application-specific assessment procedure for newly-developed US probe prototypes based on Capacitive Micromachined Ultrasonic Transducer (CMUT) technology in relation to brain imaging.
The protocol combines the use of a bovine brain fixed in formalin as the imaging target, which ensures both realism and repeatability of the described procedures, and of neuronavigation techniques borrowed from neurosurgery. The US probe is in fact connected to a motion tracking system which acquires position data and enables the superposition of US images to reference Magnetic Resonance (MR) images of the brain. This provides a means for human experts to perform a visual qualitative assessment of the US probe imaging performance and to compare acquisitions made with different probes. Moreover, the protocol relies on the use of a complete and open research and development system for US image acquisition, i.e. the Ultrasound Advanced Open Platform (ULA-OP) scanner.
The manuscript describes in detail the instruments and procedures involved in the protocol, in particular for&#160;the calibration, image acquisition and registration of US and MR images. The obtained results prove the effectiveness of the overall protocol presented, which is entirely open (within the limits of the instrumentation involved), repeatable, and covers the entire set of acquisition and processing activities for US images.

The development of new ultrasound (US) probes based on Capacitive Micromachined Ultrasonic Transducer (CMUT) technology requires an early realistic assessment of imaging capabilities. We describe a repeatable experimental protocol for US image acquisition and comparison with magnetic resonance images, using an ex vivo bovine brain as an imaging target.

The possibility to perform an early and repeatable assessment of imaging performance is fundamental in the design and development process of new ...

Revolutionizing Stroke Rehabilitation with Enhanced Grasping and Finger Recovery

A Flexible Wearable Supernumerary Robotic Limb for Chronic Stroke Patients

In this study, we present a flexible wearable supernumerary robotic limb that helps chronic stroke patients with finger rehabilitation and grasping movements. The design of this innovative limb draws inspiration from bending pneumatic muscles and the unique characteristics of an elephant's trunk tip. It places a strong emphasis on crucial factors such as lightweight construction, safety, compliance, waterproofing, and achieving a high output-to-weight/pressure ratio. The proposed structure enables the robotic limb to perform both envelope and fingertip grasping. Human-robot interaction is facilitated through a flexible bending sensor, detecting the wearer's finger movements and connecting them to motion control via a threshold segmentation method. Additionally, the system is portable for versatile daily use. To validate the effectiveness of this innovation, real-world experiments involving six chronic stroke patients and three healthy volunteers were conducted. The feedback received through questionnaires indicates that the designed mechanism holds immense promise in assisting chronic stroke patients with their daily grasping activities, potentially improving their quality of life and rehabilitation outcomes.

Author Spotlight: Enhancing Grasping Abilities for Hemiplegic Patients with Flexible Robotic Limbs 

This protocol introduces a flexible wearable supernumerary robotic limb tailored to assist in finger rehabilitation for stroke patients. The design incorporates a bending sensor to facilitate seamless human-robot interaction. Validation through experiments involving both healthy volunteers and stroke patients underscores the efficacy and dependability of the proposed study.

In this study, we present a flexible wearable supernumerary robotic limb that helps chronic stroke patients with finger rehabilitation and grasping ...

3D Ultrasound Imaging: Fast and Cost-effective Morphometry of Musculoskeletal Tissue

The developmental goal of 3D ultrasound imaging (3DUS) is to engineer a modality to perform 3D morphological ultrasound analysis of human muscles. 3DUS images are constructed from calibrated freehand 2D B-mode ultrasound images, which are positioned into a voxel array. Ultrasound (US) imaging allows quantification of muscle size, fascicle length, and angle of pennation. These morphological variables are important determinants of muscle force and length range of force exertion. The presented protocol describes an approach to determine volume and fascicle length of m.&#160;vastus lateralis and m.&#160;gastrocnemius medialis. 3DUS facilitates standardization using 3D anatomical references. This approach provides a fast and cost-effective approach for quantifying 3D morphology in skeletal muscles. In healthcare and sports, information on the morphometry of muscles is very valuable in diagnostics and/or follow-up evaluations after treatment or training.

3D ultrasound imaging (3DUS) allows fast and cost-effective morphometry of musculoskeletal tissues. We present a protocol to measure muscle volume and fascicle length using 3DUS.

The developmental goal of 3D ultrasound imaging (3DUS) is to engineer a modality to perform 3D morphological ultrasound analysis of human muscles. 3DUS ...

Medicine

Use of MRI-ultrasound Fusion to Achieve Targeted Prostate Biopsy

Here, we present a protocol to perform targeted prostate biopsy using a magnetic resonance imaging-ultrasound (MRI/US) fusion system. Prostate cancer has traditionally been diagnosed via transrectal ultrasound (TRUS) biopsy. Though considered the gold standard, TRUS is unable to visualize most prostate cancer lesions and therefore requires sampling of the entire prostate. This biopsy method often undergrades prostate cancer and fails to detect up to 35% of cancers on initial biopsy. Prostate MRI has been shown to have excellent sensitivity in the detection of cancerous lesions, and advancements in MRI technology during the last decade have led to the development of targeted biopsy. In targeted biopsy, a software platform overlays MRI data onto live TRUS images to create a fused MRI/US three-dimensional model of the prostate. Regions suspicious for malignancy on MRI are contoured by a radiologist, uploaded into the fusion system, and then displayed within the live MRI/US fused model. The urologist is then able to directly biopsy these targets. When compared to conventional TRUS biopsy, MRI/US fusion technology has been demonstrated to improve the detection of clinically significant cancer while reducing insignificant cancer detection. This technology, therefore, has the potential to diagnose prostate cancer primarily in men who would benefit from treatment.

Presented herein is a protocol to perform targeted biopsy of the prostate using an MRI-ultrasound fusion system.

Here, we present a protocol to perform targeted prostate biopsy using a magnetic resonance imaging-ultrasound (MRI/US) fusion system. Prostate cancer has ...

A High-Throughput Image-Guided Stereotactic Neuronavigation and Focused Ultrasound System for Blood-Brain Barrier Opening in Rodents

The blood-brain barrier (BBB) has been a major hurdle for the treatment of various brain diseases. Endothelial cells, connected by tight junctions, form a physiological barrier preventing large molecules (&#62;500 Da) from entering the brain tissue. Microbubble-mediated focused ultrasound (FUS) can be used to induce a transient local BBB opening, allowing larger drugs to enter the brain parenchyma.
In addition to large-scale clinical devices for clinical translation, preclinical research for therapy response assessment of drug candidates requires dedicated small animal ultrasound setups for targeted BBB opening. Preferably, these systems allow high-throughput workflows with both high-spatial precision as well as integrated cavitation monitoring, while still being cost effective in both initial investment and running costs.
Here, we present a bioluminescence and X-ray guided stereotactic small animal FUS system that is based on commercially available components and fulfills the aforementioned requirements. A particular emphasis has been placed on a high degree of automation facilitating the challenges typically encountered in high-volume preclinical drug evaluation studies. Examples of these challenges are the need for standardization in order to ensure data reproducibility, reduce intra-group variability, reduce sample size and thus comply with ethical requirements and decrease unnecessary workload. The proposed BBB system has been validated in the scope of BBB opening facilitated drug delivery trials on patient-derived xenograft models of glioblastoma multiforme and diffuse midline glioma.

The blood-brain barrier (BBB) can be temporarily disrupted with microbubble-mediated focused ultrasound (FUS). Here, we describe a step-by-step protocol for high-throughput BBB opening in vivo using a modular FUS system accessible for non-ultrasound experts.

The blood-brain barrier (BBB) has been a major hurdle for the treatment of various brain diseases. Endothelial cells, connected by tight junctions, form a ...

Neuroscience

Robotic Enucleation of an Intra-Pancreatic Insulinoma in the Pancreatic Head

Pancreatic parenchyma sparing surgery for insulinomas avoids the risk of endocrine and exocrine insufficiency, and potential high-risk anastomoses associated with pancreatic resection. Robotic surgery may be used as an alternative for open pancreatic enucleation without compromising dexterity and 3D-vision.
We present the case of a 42-year old woman who presented with sweating, tremor and episodes of hypoglycemia. A fasting test confirmed endogenic insulin overproduction. After inconclusive CT- and MRI imaging, endoscopic ultrasonography showed a hypoechoic lesion, which was fully within the pancreatic head. Although consent was obtained for pancreatoduodenectomy, robotic enucleation seemed feasible. After mobilization, intraoperative ultrasonography was used to identify the lesion and its relation with the pancreatic duct. Dissection was performed using a traction suture, hot shears and bipolar diathermia. A sealant patch was applied for hemostasis and a drain placed. The patient developed a grade B pancreatic fistula for which endoscopic sphincterotomy was performed; the surgical drain could be removed in the outpatient clinic after 20 days. Prospective studies should confirm the short- and long-term benefits of robotic enucleation of insulinomas.

Here, we present a robotic approach to enucleate an insulinoma in the pancreatic head.

Pancreatic parenchyma sparing surgery for insulinomas avoids the risk of endocrine and exocrine insufficiency, and potential high-risk anastomoses ...

Use of 3D Robotic Ultrasound for In Vivo Analysis of Mouse Kidneys

Common modalities for in vivo imaging of rodents include positron emission tomography (PET), computed tomography (CT), magnetic resonance imaging (MRI), and ultrasound (US). Each method has limitations and advantages, including availability, ease of use, cost, size, and the use of ionizing radiation or magnetic fields. This protocol describes the use of 3D robotic US for in vivo imaging of rodent kidneys and heart, subsequent data analysis, and possible research applications. Practical applications of robotic US are the quantification of total kidney volume (TKV), as well as the measurement of cysts, tumors, and vasculature. Although the resolution is not as high as other modalities, robotic US allows for more practical high throughput data collection. Furthermore, using US M-mode imaging, cardiac function may be quantified. Since the kidneys receive 20%-25% of the cardiac output, assessing cardiac function is critical to the understanding of kidney physiology and pathophysiology.

Use of 3D Robotic Ultrasound for In Vivo Analysis of Mouse Kidneys

This protocol demonstrates robotic ultrasound (US) as a practical, cost-effective, and quick alternative to traditional non-invasive image modalities.

Common modalities for in vivo imaging of rodents include positron emission tomography (PET), computed tomography (CT), magnetic resonance imaging (MRI), ...

Design and Implementation of a Bespoke Robotic Manipulator for Extra-corporeal Ultrasound

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