Hugo Rodrigue

Layer jamming brakes exhibit variable stiffness with vacuum pressure, allowing them to restrict relative motion between two points. These devices hold significant potential for wearable applications due to their lightweight nature and ability to generate substantial linear tension for load transfer or selective movement restriction. However, the challenge of integrating displacement sensors within their structure has not yet been solved. In this article, we introduce a layer jamming system with resistive sensing jamming layers. The proposed mechanism leverages the relative motion of internal overlapping sensing jamming layers to produce a variation in resistance which can inform the user about their relative displacement while also producing frictional forces. This sensing approach is inherently synergistic with the mechanism of the device as it simultaneously generates friction and enables real-time displacement measurement without altering the shape of the device. The proposed device can generate a tensile force of up to 1017 N, can sense displacements over the entire range of operation of jamming layer brakes (up to 82% displacement) with a gauge factor of 1.15 and a linearity error within 1%. We demonstrate its application as a wearable device with a controllable braking point algorithm and as an upper-arm support system.

This article presents ROGIBOT, an autonomous robot designed for high-speed unloading inside standard containers. Previous unloading robots have typically been limited to handling only box-shaped packages and a small number of items at a time. These limitations hinder their applicability in general logistics environments, which involve a wide variety of package types and require high throughput. To address these challenges, we propose a novel dual-arm robot equipped with multifunctional end effectors, including a vacuum array, a two-finger gripper, and an on-hand sliding surface. The components are designed to handle the most common types of logistics packages, such as boxes, plastic pouches, and bundle sacks. In particular, the on-hand sliding surface can draw packages efficiently using the frictional force generated by a rotating elastic conveyor belt. This enables the robot to unload multiple packages consecutively at high speed by sweeping the end effectors across the pile. In addition to the hardware, we introduce a package recognition method and a finite-state-machine (FSM)-based task planner that detects logistics packages and selects actions to maximize operational efficiency. In our evaluation, ROGIBOT was tested in a mock container and achieved a throughput of 2,030 pieces (packages) per hour (PPH), surpassing both state-of-the-art (SOTA) robots and typical human performance.

Robots made from soft and compliant materials offer a promising alternative to traditional rigid robots, particularly in human–robot collaborative environments due to their inherent safety. Pneumatic artificial muscles (PAMs) play a critical role in this field, serving as compliant actuators capable of generating substantial forces. However, this type of actuator still faces challenges in generating bidirectional force over a large range of motion. In this article, we introduce a three-dimensional (3-D)-printed PAM with a telescopic structure using a nested structure. The actuator's large volumetric deformation enables it to generate high bidirectional forces using positive and negative pressures, while also providing a wide range of motion with significant extension and contraction ratios. The use of 3-D printing not only simplifies the design and fabrication process but also offers significant advantages in mass production and industrial implementation. The proposed actuator can generate an extension blocked force of 659 N with an extension ratio of 447.1% and contract with payloads up to 7 kg up to a contraction ratio of 76.9%. A rotational configuration of the actuator is also presented with a blocked torque of 18.5 Nm. These actuators were then implemented into grippers and extendable links for robotic manipulators.

This study presents a novel synergistic actuator integrating thermo-pneumatic actuation and shape memory alloy (SMA) springs, achieving distinct operational modes with a single energy input. Conventional artificial muscles typically rely on a single actuation mechanism, limiting functionality. By combining thermo-pneumatic and SMA-based actuation, this actuator achieves cooperative, composite, and antagonistic modes without the use of a pneumatic pump. The cooperative mode utilizes the simultaneous actuation of both mechanisms to increase force and displacement output. The composite mode enables distinct actuation tasks, demonstrated through a soft robotic gripper capable of shape-adaptive grasping. The antagonistic mode exploits the opposing force generation of the two actuation sources by using a vacuum-based thermo-pneumatic actuator, facilitating bidirectional motions without additional bias mechanisms. Experimental evaluations confirmed improved force outputs and controllability under payload conditions with the actuator lifting payloads up to 20 kg. A thermodynamic model was combined with a quasi-static force model to predict the behavior of the actuator. The proposed actuator concept enables pumpless actuation of an actuation with two actuation sources using a single energy input and increases the performance of the actuator versus using a single actuation source while increasing the versatility of the actuator through its various modes of operation.

This paper introduces a novel origami-inspired vacuum pneumatic actuator that operates as a passive forcegenerating element, capable of producing a near-constant force without active control. The actuator is fabricated from a Yoshimura-patterned film structure incorporating rigid facets and internal reinforcements, enabling large contraction strokes and consistent force output under constant vacuum conditions. A central feature of the design is its pre-vacuumed, sealed operation, which maintains stable internal pressure throughout the entire stroke without needing external pressure regulation. The combination of stable passive pressure and stable isobaric force results in a constant and passive force generated by the actuator. A numerical model based on conservation of energy and Boyle's law is presented to predict actuator behavior under both isobaric and constant-mass conditions. Experimental validation confirms the model's accuracy and demonstrates the actuator's stable force output at high constant-mass pressures. The actuator is further implemented in a wearable support suit aimed at reducing lower back strain during squatting and stooping motions. This work demonstrates a new approach for passive actuation using soft robotics principles and highlights potential applications in assistive wearable devices.

Soft robotic layer jamming devices enable controlled movement restrictions through the application of vacuum pressure on jamming layers. Traditional vacuum-based layer jamming systems, however, have limitations such as a force that decreases throughout the deformation due to a decrease in the contact area of the jamming layers and are restricted to an increase in length equal to their initial length. This works proposes a rollable layer jamming device (RLJD) which offers a solution to these problems. This device leverages rolled and stacked films to overcome limitations in linear extension by storing the jamming layers compactly inside of a reel. Also, its tensile force increases throughout the deformation due to the frictional force between the polymer and the layers which increases as the radius decreases, effectively addressing the problem of force reduction encountered in conventional layer jamming systems. This paper details the device manufacturing process, introduces an analytical model that predicts the performance of the device and presents experimental results for various device parameters. The RLJD has been successfully incorporated as a wearable robot that provides support for both the upper limbs and the lower back when lifting and carrying objects.