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 Deerfield Beach



The Robot and the Philosopher

The New Yorker

In the age of A.I., we endlessly debate what consciousness looks like. Can a camera see things more clearly? Earlier that day, she'd been onstage at the conference I was attending and had been teased for a gesture that looked as though she were flipping off the audience. Now she was in the hotel lobby, in a black gown, holding court. She stepped in front of a bright-orange wall. I had brought an 85-mm. "What are your hopes for the future of humanity?" She wasn't keen to answer, but she responded to the camera.


Reconfigurable Auxetic Devices (RADs) for Robotic Surface Manipulation

Miske, Jacob, Maya, Ahyan, Inkiad, Ahnaf, Lipton, Jeffrey Ian

arXiv.org Artificial Intelligence

Robotic surfaces traditionally use materials with a positive Poisson's ratio to push and pull on a manipulation interface. Auxetic materials with a negative Poisson's ratio may expand in multiple directions when stretched and enable conformable interfaces. Here we demonstrate reconfigurable auxetic lattices for robotic surface manipulation. Our approach enables shape control through reconfigurable locking or embedded servos that underactuate an auxetic lattice structure. Variable expansion of local lattice areas is enabled by backlash between unit cells. Demonstrations of variable surface conformity are presented with characterization metrics. Experimental results are validated against a simplified model of the system, which uses an activation function to model intercell coupling with backlash. Reconfigurable auxetic structures are shown to achieve manipulation via variable surface contraction and expansion. This structure maintains compliance with backlash in contrast with previous work on auxetics, opening new opportunities in adaptive robotic structures for surface manipulation tasks.



Multi-fidelity Bayesian Data-Driven Design of Energy Absorbing Spinodoid Cellular Structures

Guo, Leo, Kansara, Hirak, Khosroshahi, Siamak F., Zhang, GuoQi, Tan, Wei

arXiv.org Artificial Intelligence

Finite element (FE) simulations of structures and materials are getting increasingly more accurate, but also more computationally expensive as a collateral result. This development happens in parallel with a growing demand of data-driven design. To reconcile the two, a robust and data-efficient optimization method called Bayesian optimization (BO) has been previously established as a technique to optimize expensive objective functions. In parallel, the mesh width of an FE model can be exploited to evaluate an objective at a lower or higher fidelity (cost & accuracy) level. The multi-fidelity setting applied to BO, called multi-fidelity BO (MFBO), has also seen previous success. However, BO and MFBO have not seen a direct comparison with when faced with with a real-life engineering problem, such as metamaterial design for deformation and absorption qualities. Moreover, sampling quality and assessing design parameter sensitivity is often an underrepresented part of data-driven design. This paper aims to address these shortcomings by employing Sobol' samples with variance-based sensitivity analysis in order to reduce design problem complexity. Furthermore, this work describes, implements, applies and compares the performance BO with that MFBO when maximizing the energy absorption (EA) problem of spinodoid cellular structures is concerned. The findings show that MFBO is an effective way to maximize the EA of a spinodoid structure and is able to outperform BO by up to 11% across various hyperparameter settings. The results, which are made open-source, serve to support the utility of multi-fidelity techniques across expensive data-driven design problems.


Navigation of a Three-Link Microswimmer via Deep Reinforcement Learning

Lai, Yuyang, Heydari, Sina, Pak, On Shun, Man, Yi

arXiv.org Artificial Intelligence

Motile microorganisms develop effective swimming gaits to adapt to complex biological environments. Translating this adaptability to smart microrobots presents significant challenges in motion planning and stroke design. In this work, we explore the use of reinforcement learning (RL) to develop stroke patterns for targeted navigation in a three-link swimmer model at low Reynolds numbers. Specifically, we design two RL-based strategies: one focusing on maximizing velocity (Velocity-Focused Strategy) and another balancing velocity with energy consumption (Energy-Aware Strategy). Our results demonstrate how the use of different reward functions influences the resulting stroke patterns developed via RL, which are compared with those obtained from traditional optimization methods. Furthermore, we showcase the capability of the RL-powered swimmer in adapting its stroke patterns in performing different navigation tasks, including tracing complex trajectories and pursuing moving targets. Taken together, this work highlights the potential of reinforcement learning as a versatile tool for designing efficient and adaptive microswimmers capable of sophisticated maneuvers in complex environments.


QuantU-Net: Efficient Wearable Medical Imaging Using Bitwidth as a Trainable Parameter

Boerkamp, Christiaan, Thomas, Akhil John

arXiv.org Artificial Intelligence

Medical image segmentation, particularly tumor segmentation, is a critical task in medical imaging, with U-Net being a widely adopted convolutional neural network (CNN) architecture for this purpose. However, U-Net's high computational and memory requirements pose challenges for deployment on resource-constrained devices such as wearable medical systems. This paper addresses these challenges by introducing QuantU-Net, a quantized version of U-Net optimized for efficient deployment on low-power devices like Field-Programmable Gate Arrays (FPGAs). Using Brevitas, a PyTorch library for quantization-aware training, we quantize the U-Net model, reducing its precision to an average of 4.24 bits while maintaining a validation accuracy of 94.25%, only 1.89% lower than the floating-point baseline. The quantized model achieves an approximately 8x reduction in size, making it suitable for real-time applications in wearable medical devices. We employ a custom loss function that combines Binary Cross-Entropy (BCE) Loss, Dice Loss, and a bitwidth loss function to optimize both segmentation accuracy and the size of the model. Using this custom loss function, we have significantly reduced the training time required to find an optimal combination of bitwidth and accuracy from a hypothetical 6^23 number of training sessions to a single training session. The model's usage of integer arithmetic highlights its potential for deployment on FPGAs and other designated AI accelerator hardware. This work advances the field of medical image segmentation by enabling the deployment of deep learning models on resource-constrained devices, paving the way for real-time, low-power diagnostic solutions in wearable healthcare applications.


Dynamic neural network with memristive CIM and CAM for 2D and 3D vision

Zhang, Yue, Zhang, Woyu, Wang, Shaocong, Lin, Ning, Yu, Yifei, He, Yangu, Wang, Bo, Jiang, Hao, Lin, Peng, Xu, Xiaoxin, Qi, Xiaojuan, Wang, Zhongrui, Zhang, Xumeng, Shang, Dashan, Liu, Qi, Cheng, Kwang-Ting, Liu, Ming

arXiv.org Artificial Intelligence

The brain is dynamic, associative and efficient. It reconfigures by associating the inputs with past experiences, with fused memory and processing. In contrast, AI models are static, unable to associate inputs with past experiences, and run on digital computers with physically separated memory and processing. We propose a hardware-software co-design, a semantic memory-based dynamic neural network (DNN) using memristor. The network associates incoming data with the past experience stored as semantic vectors. The network and the semantic memory are physically implemented on noise-robust ternary memristor-based Computing-In-Memory (CIM) and Content-Addressable Memory (CAM) circuits, respectively. We validate our co-designs, using a 40nm memristor macro, on ResNet and PointNet++ for classifying images and 3D points from the MNIST and ModelNet datasets, which not only achieves accuracy on par with software but also a 48.1% and 15.9% reduction in computational budget. Moreover, it delivers a 77.6% and 93.3% reduction in energy consumption.


Communication Modalities

Kuznets, Roman

arXiv.org Artificial Intelligence

Epistemic analysis of distributed systems is one of the biggest successes among applications of logic in computer science. The reason for that is that agents' actions are necessarily guided by their knowledge. Thus, epistemic modal logic, with its knowledge and belief modalities (and group versions thereof), has played a vital role in establishing both impossibility results and necessary conditions for solvable distributed tasks. In distributed systems, knowledge is largely attained via communication. It has been standard in both distributed systems and dynamic epistemic logic to treat incoming messages as trustworthy, thus, creating difficulties in the epistemic analysis of byzantine distributed systems where faulty agents may lie. In this paper, we argue that handling such communication scenarios calls for additional modalities representing the informational content of messages that should not be taken at face value. We present two such modalities: hope for the case of fully byzantine agents and creed for non-uniform communication protocols in general.


Pruning random resistive memory for optimizing analogue AI

Li, Yi, Wang, Songqi, Zhao, Yaping, Wang, Shaocong, Zhang, Woyu, He, Yangu, Lin, Ning, Cui, Binbin, Chen, Xi, Zhang, Shiming, Jiang, Hao, Lin, Peng, Zhang, Xumeng, Qi, Xiaojuan, Wang, Zhongrui, Xu, Xiaoxin, Shang, Dashan, Liu, Qi, Cheng, Kwang-Ting, Liu, Ming

arXiv.org Artificial Intelligence

The rapid advancement of artificial intelligence (AI) has been marked by the large language models exhibiting human-like intelligence. However, these models also present unprecedented challenges to energy consumption and environmental sustainability. One promising solution is to revisit analogue computing, a technique that predates digital computing and exploits emerging analogue electronic devices, such as resistive memory, which features in-memory computing, high scalability, and nonvolatility. However, analogue computing still faces the same challenges as before: programming nonidealities and expensive programming due to the underlying devices physics. Here, we report a universal solution, software-hardware co-design using structural plasticity-inspired edge pruning to optimize the topology of a randomly weighted analogue resistive memory neural network. Software-wise, the topology of a randomly weighted neural network is optimized by pruning connections rather than precisely tuning resistive memory weights. Hardware-wise, we reveal the physical origin of the programming stochasticity using transmission electron microscopy, which is leveraged for large-scale and low-cost implementation of an overparameterized random neural network containing high-performance sub-networks. We implemented the co-design on a 40nm 256K resistive memory macro, observing 17.3% and 19.9% accuracy improvements in image and audio classification on FashionMNIST and Spoken digits datasets, as well as 9.8% (2%) improvement in PR (ROC) in image segmentation on DRIVE datasets, respectively. This is accompanied by 82.1%, 51.2%, and 99.8% improvement in energy efficiency thanks to analogue in-memory computing. By embracing the intrinsic stochasticity and in-memory computing, this work may solve the biggest obstacle of analogue computing systems and thus unleash their immense potential for next-generation AI hardware.