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1. Invited: Can Wi-R enable perpetual IoB nodes?

   https://doi.org/10.1109/BioCAS58349.2023.10388539  

   Datta, Arunashish; Sen, Shreyas (October 2023, IEEE)

   While the number of wearables is steadily growing, the wearables/person wearing them faces a limitation due to the need for charging all of them every day. To unlock the true power of IoB, we need to make these IoB nodes perpetual. However, that is not possible with today’s technology. In this paper, we will debate, whether with the advent of Wi-R protocol that uses the body to communicate at 100X lower energy that BTLE/Wi-Fi, is it going to be possible to enable the long-standing desire of perpetual sensing/actuation nodes for the Internet of Bodies. 

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2. Towards Functional Mobile Microrobotic Systems

   https://doi.org/10.3390/robotics8030069  

   Adam, Georges; Chowdhury, Sagar; Guix, Maria; Johnson, Benjamin V.; Bi, Chenghao; Cappelleri, David (September 2019, Robotics)

   This paper presents our work over the last decade in developing functional microrobotic systems, which include wireless actuation of microrobots to traverse complex surfaces, addition of sensing capabilities, and independent actuation of swarms of microrobots. We will discuss our work on the design, fabrication, and testing of a number of different mobile microrobots that are able to achieve these goals. These microrobots include the microscale magnetorestrictive asymmetric bimorph microrobot ( μ MAB), our first attempt at magnetic actuation in the microscale; the microscale tumbling microrobot ( μ TUM), our microrobot capable of traversing complex surfaces in both wet and dry conditions; and the micro-force sensing magnetic microrobot ( μ FSMM), which is capable of real-time micro-force sensing feedback to the user as well as intuitive wireless actuation. Additionally, we will present our latest results on using local magnetic field actuation for independent control of multiple microrobots in the same workspace for microassembly tasks. 

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3. Frequency and leg stiffness adaptation in human vertical hopping before, during and after added load

   https://doi.org/10.1242/jeb.250848  

   Jessup, Luke N; Williams, Moira A; Duman, Alex J; Lee, Juwon; Konanur, Raksha S; Silverman, Anne K; Finley, James M; Daley, Monica A; Voloshina, Alexandra S (October 2025, Journal of Experimental Biology)

   ABSTRACT Terrestrial animal gaits often use spring-like mechanics to enhance movement economy through elastic energy cycling. Hopping is a relatively simple, constrained task, yet retains essential features of bouncing gaits, requiring cyclic regulation of limb stiffness and generation of high muscle forces to support body weight and enable elastic energy cycling. We investigated how humans adjust hopping frequency and leg stiffness before, during and after experiencing added load. Eighteen participants hopped bipedally for 90 s per trial, with hop frequency and height unconstrained, while kinematic, ground reaction force and ankle muscle electromyographic (EMG) data were collected. We analysed mechanics across four conditions: initial body weight (BWi), two added mass trials (+10% and +20% BW) and final body weight (BWf). With added mass, participants increased leg stiffness and maintained a consistent hopping frequency (∼2.15 Hz); yet, when returning to BWf, the elevated leg stiffness was maintained and hopping frequency increased (to ∼2.36 Hz) and reduced centre of mass (CoM) work per hop. BWf adaptations were driven by greater ankle stiffness, leading to less ankle work. Adaptation rates were consistent across trials, with steady-state mechanics reached in ∼30–40 s. Muscle coactivation decreased following BWi. Triceps surae mean EMG was unchanged with added mass and reduced in BWf. Similar patterns of adaptation were observed in bouncing without an aerial phase. Substantial inter-individual variability was observed in preferred hopping mechanics and adaptation strategy. Together, added mass and increased task familiarity led participants to recalibrate their hopping strategy. Based on literature evidence, the adaptations may align with reduced metabolic cost. 

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4. How to Stick the Landing: Kangaroo Rats Use Their Tails to Reorient during Evasive Jumps Away from Predators

   https://doi.org/10.1093/icb/icab043  

   Schwaner, M Janneke; Freymiller, Grace A; Clark, Rulon W; McGowan, Craig P (May 2021, Integrative and Comparative Biology)

   Synopsis Tails are widespread in the animal world and play important roles in locomotor tasks, such as propulsion, maneuvering, stability, and manipulation of objects. Kangaroo rats, bipedal hopping rodents, use their tail for balancing during hopping, but the role of their tail during the vertical evasive escape jumps they perform when attacked by predators is yet to be determined. Because we observed kangaroo rats swinging their tails around their bodies while airborne following escape jumps, we hypothesized that kangaroo rats use their tails to not only stabilize their bodies while airborne, but also to perform aerial re-orientations. We collected video data from free-ranging desert kangaroo rats (Dipodomys deserti) performing escape jumps in response to a simulated predator attack and analyzed the rotation of their bodies and tails in the yaw plane (about the vertical-axis). Kangaroo rat escape responses were highly variable. The magnitude of body re-orientation in yaw was independent of jump height, jump distance, and aerial time. Kangaroo rats exhibited a stepwise re-orientation while airborne, in which slower turning periods corresponded with the tail center of mass being aligned close to the vertical rotation axis of the body. To examine the effect of tail motion on body re-orientation during a jump, we compared average rate of change in angular momentum. Rate of change in tail angular momentum was nearly proportional to that of the body, indicating that the tail reorients the body in the yaw plane during aerial escape leaps by kangaroo rats. Although kangaroo rats make dynamic 3D movements during their escape leaps, our data suggest that kangaroo rats use their tails to control orientation in the yaw plane. Additionally, we show that kangaroo rats rarely use their tail length at full potential in yaw, suggesting the importance of tail movement through multiple planes simultaneously. 

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5. BIOGEM: A Fully Biodegradable Gelatin-Based McKibben Actuator with Embedded Sensing

   https://doi.org/10.1145/3746059.3747687  

   Ge, Gaolin; Lu, Haoran; Gao, Yingting; Yang, Qifeng; Hester, Josiah; Cheng, Tingyu; Luo, Yiyue (September 2025, ACM)

   We present BIOGEM, a fully biodegradable McKibben actuator with integrated sensing, made from gelatin-based composites. By tailoring the material compositions, we customize the mechanical and electrical properties of the biodegradable composites, creating an integrated biodegradable system that combines both actuation and sensing functionalities. BIOGEM integrates a McKibben actuating structure by using stiff gelatin as outer braiding and the stretchable gelatin as air chambers. It also integrates resistive strain sensing through ionic gelatin, allowing the actuator to monitor its own deformation without relying on conventional electronics. We characterize the actuator’s performance across key parameters including braid angle, wall thickness, and material stiffness, demonstrating reliable contraction and repeatable force output at low pressures. Biodegradation is validated through both enzyme-assisted and backyard soil studies, confirming the material’s sustainable end-of-life behavior under realistic conditions. We illustrate the potential of this platform through interactive, edible, and environmentally-degradable prototypes across human–computer interaction and soft robotics scenarios. 

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