Periodic Reporting for period 3 - SoMMoR (Soft-bodied Miniature Mobile Robots)
Période du rapport: 2022-09-01 au 2024-08-31
Untethered mobile milli/microrobots would have a radical impact in medicine. Such untethered tiny machines could access smaller regions inside the body, remain inside the body for long durations as semi-implantable medical devices, and enable diagnostic and therapeutic medical operations in hard or currently not possible to reach regions inside the body with minimal or no invasion. While many groups have been working intensely on creating such new machines for potential medical applications, there are still many significant challenges that must be addressed: 3D design, fabrication and materials of safe and multi-functional medical mobile robots down to tens of micrometer size scale, robust locomotion of these robots inside the complex human body, precise navigation control under medical imaging modalities, integrating diagnostic and therapeutic medical functions to them, and demonstrating their clinically relevant medical applications in in vivo animal models.
To address these challenges, we propose to create new soft-bodied mobile milli/microrobots with medical functions and sizes down to tens of micron scale to address the above challenges of untethered miniature robots. Such shape-programmable tiny soft machines will be created from biocompatible magnetic soft composite materials, will be actuated by external magnetic fields or gradients, will have multimodal robust locomotion capability, integrated medical functions and safe interactions inside the human body, will be tracked by real-time medical imaging systems, and will be demonstrated in clinically relevant active local cargo (e.g. drug) delivery, remote heating-based coagulation and hyperthermia, and deliberate vessel and tube clogging applications. Research tasks of the robot design, fabrication and materials, robot actuation, locomotion and control, robot medical functions, and robot characterization and in vitro, ex vivo and in vivo testing will be performed to achieve our research objectives.
To address these challenges, we propose to create new soft-bodied mobile milli/microrobots with medical functions and sizes down to tens of micron scale to address the above challenges of untethered miniature robots. Such shape-programmable tiny soft machines will be created from biocompatible magnetic soft composite materials, will be actuated by external magnetic fields or gradients, will have multimodal robust locomotion capability, integrated medical functions and safe interactions inside the human body, will be tracked by real-time medical imaging systems, and will be demonstrated in clinically relevant active local cargo (e.g. drug) delivery, remote heating-based coagulation and hyperthermia, and deliberate vessel and tube clogging applications. Research tasks of the robot design, fabrication and materials, robot actuation, locomotion and control, robot medical functions, and robot characterization and in vitro, ex vivo and in vivo testing will be performed to achieve our research objectives.
1. We developed a novel assembly-based voxelated fabrication technique to fabricate new 3D soft millirobots with multimaterials and complex magnetization programming for the first time. This pioneering work was published in Science Robotics. This technique enabled us to prototype a wireless soft peristaltic pump with 1 mm diameter, a wireless drug-ejecting soft microcapsule with 500 micrometer diameter, a wireless anchoring inside the blood vasculature, etc. type of novel wireless soft medical devices for the first time.
2. We advanced our theoretical and experimental understanding of the soft-bodied adaptive multimodal locomotion strategies in fluid-filled confined spaces, such as inside the human body. We showed that body undulation of soft sheet-shaped of robots inside narrow channels can induce swimming or surface crawling behavior as a function of the gap size, robot actuation and geometric parameters, and fluid viscosity. We also demonstrated locomotion inside ear channel type of complex body sites using such soft-bodied locomotion robot for the first time. This work was published in Science Advances.
3. We advanced our liquid crystal elastomers (LCE)-based soft miniature robotics research task significantly in this term. We showed shape-programmable liquid crystal elastomer structures with arbitrary 3D director fields and geometries for the first time using our assembly-based new fabrication technique (achievement 1). This work was published in Nature Communications. Moreover, we demonstrated that LCEs magnetic composites can enable multimodal (thermal and magnetic) actuation for wireless soft miniature robots for more complex shape reconfiguration and programming capabilities. Finally, we proposed LCE-actuated reconfigurable microscale kirigami metastructures for the first time. These last two works were published in Advanced Materials.
4. We scaled down our magnetic soft miniature robot concept down to a few microns (i.e. single biological cell) size scale for the first time. Combining two-photon polymerization and magnetic assembly, we could create magnetic soft micromachines made of linked microactuator networks. This work was published in Science Advances.
5. I wrote a perspective article on physical intelligence as a new paradigm, where our soft miniature robots have physical intelligence capabilities due to their soft body reconfigurable shape and stiffness programming and stimuli-responsive LCE type of smart materials/mechanisms/structures. This article would be a milestone for this new emerging field.
6. We showed the effect of body stiffness distribution on larval fish–like efficient undulatory swimming for the first time, where different body undulation speeds have energy-efficient different body stiffness distributions.
7. In the learning and control-related task of our soft miniature robots, we proposed a new method for task space adaptation via the learning of gait controllers of magnetic soft millirobots.
2. We advanced our theoretical and experimental understanding of the soft-bodied adaptive multimodal locomotion strategies in fluid-filled confined spaces, such as inside the human body. We showed that body undulation of soft sheet-shaped of robots inside narrow channels can induce swimming or surface crawling behavior as a function of the gap size, robot actuation and geometric parameters, and fluid viscosity. We also demonstrated locomotion inside ear channel type of complex body sites using such soft-bodied locomotion robot for the first time. This work was published in Science Advances.
3. We advanced our liquid crystal elastomers (LCE)-based soft miniature robotics research task significantly in this term. We showed shape-programmable liquid crystal elastomer structures with arbitrary 3D director fields and geometries for the first time using our assembly-based new fabrication technique (achievement 1). This work was published in Nature Communications. Moreover, we demonstrated that LCEs magnetic composites can enable multimodal (thermal and magnetic) actuation for wireless soft miniature robots for more complex shape reconfiguration and programming capabilities. Finally, we proposed LCE-actuated reconfigurable microscale kirigami metastructures for the first time. These last two works were published in Advanced Materials.
4. We scaled down our magnetic soft miniature robot concept down to a few microns (i.e. single biological cell) size scale for the first time. Combining two-photon polymerization and magnetic assembly, we could create magnetic soft micromachines made of linked microactuator networks. This work was published in Science Advances.
5. I wrote a perspective article on physical intelligence as a new paradigm, where our soft miniature robots have physical intelligence capabilities due to their soft body reconfigurable shape and stiffness programming and stimuli-responsive LCE type of smart materials/mechanisms/structures. This article would be a milestone for this new emerging field.
6. We showed the effect of body stiffness distribution on larval fish–like efficient undulatory swimming for the first time, where different body undulation speeds have energy-efficient different body stiffness distributions.
7. In the learning and control-related task of our soft miniature robots, we proposed a new method for task space adaptation via the learning of gait controllers of magnetic soft millirobots.
We have developed new design, fabrication, navigation, tracking and control methodologies for creating wireless soft miniature robots for various minimally invasive medical device applications inside the human body for the first time. Our recent assembly-based 3D soft millirobot fabrication method with multimaterials and wireless soft medical devices enabled by such method is a breakthrough. All of the high-impact publications in this project have advanced the soft robotics research field significantly beyond the state of the art. Due to such breakthroughs, Prof. Sitti received the Breakthrough of the Year Award in the Engineering and Technology Category in Falling Walls World Science Summit in Berlin, Germany in 2020, he was selected as a Highly Cited Researcher in 2021, and he and his researchers were one of the two Cozzarelli Prize Finalists in the Engineering and Applied Sciences category in the PNAS journal in 2020.
We have mostly planned these breakthroughs through our previous knowledge and expertise; however, some experimental discoveries have been unexpected due to the complex mechanics and physics of our soft miniature robots. Our above research achievements have been possible with a highly interdisciplinary (e.g. materials science, robotics, mechanics, microtechnology, medical devices), innovative and disruptive research approach and team. We have been filing many patents due to many inventions. Such IP will be transferred exclusively to a startup that Prof. Sitti will found in the near future in Germany.
We have mostly planned these breakthroughs through our previous knowledge and expertise; however, some experimental discoveries have been unexpected due to the complex mechanics and physics of our soft miniature robots. Our above research achievements have been possible with a highly interdisciplinary (e.g. materials science, robotics, mechanics, microtechnology, medical devices), innovative and disruptive research approach and team. We have been filing many patents due to many inventions. Such IP will be transferred exclusively to a startup that Prof. Sitti will found in the near future in Germany.