This paper introduces Model Q-II, an enhanced underactuated robotic hand designed to improve dexterous manipulation through expanded grasping modes and manipulation primitives. The Model Q-II incorporates tripod and enhanced power grasping modes, achieving increased versatility without adding additional actuators. The design employs passive mechanisms, such as lateral contact walls and a finger-locking system, to facilitate seamless transitions between modes, enabling precise pinch-to-tripod and pinch-to-power gating. These enhancements allow the hand to perform complex in-hand manipulations, including multi-directional object positioning. Theoretical analysis, simulations, and experimental evaluations validate the hand's performance, demonstrating improved grasping force, range, and manipulation capabilities. The results highlight Model Q-II's ability to handle various tasks, offering a robust, cost-effective solution for applications requiring both precise and powerful grasping.

Precision gas analyzers are widely used in ecological research for manual measurement of soil carbon flux, a key metric used in the study of climate change. We present a generational update to the first low-cost, autonomous, closed-chamber style soil CO2 flux sensors (Fluxbots). Fluxbot 2.0 is the first such low-cost autonomous flux chamber capable of real-time wireless data transmission, which enables ecologists conducting in situ soil carbon flux surveys to set up their own wireless sensor arrays, reporting carbon flux data in real time at a very high level of temporal resolution. The system’s low cost (less than 500 USD per unit) and long-range cellular data transmission capabilities also allow for greatly improved spatial resolution. Additionally, the updated system consumes significantly less power, resulting in the ability to be deployed for longer than 10 × the battery lifetime of the original version on a single charge.

Robot manipulation today generally focuses on motions exclusively with a robot arm or a dexterous hand, but usually not a combination of both. However, complex manipulation tasks can require coordinating arm and hand motions that leverage capabilities of both, much like the coordinated arm and hand motions carried out by humans to perform everyday tasks. In this work, we evaluate unified manipulation with robot arms and dexterous hands, using a motion optimization framework that synthesizes a series of configuration states over the entire manipulation system. We characterize the possible benefits of unifying arm and dexterous hand capabilities within a single model via metrics such as pose accuracy, manipulability, joint-space smoothness, distance to joint-limits, distance to collisions, and more. Several arm-hand combinations are quantitatively compared in simulation on a variety of experiment tasks and performance measures. Our results suggest that combining motions from robot arms and dexterous hands indeed has compelling benefits, highlighting the exciting potential of continued progress in unified arm-hand motion synthesis for robotics applications.

Rotating a grasped object about all three spatial axes is challenging, because kinematically redundant robot hands require complex control schemes for within-hand rotations, and simple parallel grippers require inefficient whole arm motions. We present a novel 3-finger robot hand design inspired by a spherical parallel mechanism that achieves these rotations with just 3 actuators. The hand is designed such that at every hand-object configuration, the object pose moves along a sphere with a fixed center, which is determined by the intersection of the fingers’ revolute axes and is independent of the object shape, pose, and the initial grasp configuration. We optimize the hand based on 3-RRS spherical manipulator to maximize both its rotational workspace size and manipulation motion quality. From these parameters, we implement and experimentally evaluate the hand design through grasping tests, manipulation characterization, and real-world task scenarios, which show that the hand is able to grasp a variety of object geometries and accomplish precise single and multi-DOF rotations about a fixed point. We believe this design can remarkably improve robustness and simplify control for dexterous within-hand rotations, which finds utility in augmenting the capabilities of low-DOF robot arms without an active wrist.

Grasping can be conceptualized as the ability of an end-effector to temporarily attach or fixture an object to a manipulator-constraining all motion of the workpiece with respect to the end-effector's base frame. This seemingly simplistic action often requires excessive sensing, computation, or control to achieve with multi-fingered hands, which can be mitigated with underactuated mechanisms. In this work, we present the analysis of radial graspers for automated part fixturing and grasping in the plane with a design implementation of a single-actuator, 8-finger gripper. By leveraging a passively adaptable mechanism that is under-constrained pre-contact, the gripper conforms to arbitrary object geometries and locks post-contact as to provide form closure around the object. We also justify that 8 radially symmetric fingers with passive locking are sufficient to create robust form closure grasps on arbitrary planar objects. The underlying mechanism of the gripper is described in detail, with analysis of its highly underactuated nature, and the resulting form closure ability. We show with a wide variety of objects that the gripper is able to acquire robust grasps on all of them, and maintain maximal quality form closure on most objects, with each finger exerting equal grasp force within ±2.48 N.