45 accepted papers
Dense collections of movable objects are common in everyday spaces-from cabinets in a home to shelves in a warehouse. Safely retracting objects from such collections is difficult for robots, yet people do it frequently, leveraging learned experience in tandem with vision and non-prehensile tactile s
Imitation learning requires high-quality demonstrations consisting of sequences of state-action pairs. For contact-rich dexterous manipulation tasks that require dexterity, the actions in these state-action pairs must produce the right forces. Current widely-used methods for collecting dexterous man
Operation in constrained and cluttered spaces poses a challenge for robotic manipulators, in part due to their bulky link geometry and kinematic limitations in comparison to human hands and arms. To address these limitations, we introduce SLIM, a custom end-effector consisting of a bidirectional han
Tactile sensing is essential for dexterous manipulation, yet large-scale human demonstration datasets lack tactile feedback, limiting their effectiveness in skill transfer to robots. To address this, we introduce TacCap, a wearable Fiber Bragg Grating (FBG)-based tactile sensor designed for seamless
Aquatic mammals use whiskers to detect and discriminate objects and analyze water movements, inspiring the development of robotic whiskers for sensing contacts, surfaces, and water flows. We present the design and application of underwater whisker sensors based on Fiber Bragg Grating (FBG) technolog
We present a solution to the separate challenges faced by suction cups and gecko adhesives for one-sided grasping of heavy, irregular items. The gripping technology combines suction with adhesion for grasping and placing a wide range of objects in packed spaces. Applications include shopping and res
We present an integrated pneumatic sensor and actuator for soft haptic devices that can estimate contact force, location, and shape using a multi-headed neural network. The sensor uses channels cast into a multi-layer silicone bubble that change flow resistance as the bubble deforms, allowing measur
ReachBot is a robot that uses extendable and retractable booms as limbs to move around unpredictable environments such as martian caves. Each boom is capped by a microspine gripper designed for grasping rocky surfaces. Motion planning for ReachBot must be versatile to accommo-date variable terrain f…
A largely untapped potential for aerial robots is to capture airborne targets in flight. We present an approach in which a simple dynamic model of a quadrotor/target interaction leads to the design of a gripper and associated velocity sufficiency region with a high probability of capture. A model of
We present hybrid adhesive end-effectors for bimanual handling of deformable objects. The gripping system is driven by the need to achieve alignment on deformable and irregular surfaces while maintaining a large area of contact for efficient use of the adhesive. The objective of the gripping system
When humans socially interact with another agent (e.g., human, pet, or robot) through touch, they do so by applying varying amounts of force with different directions, locations, contact areas, and durations. While previous work on touch gesture recognition has focused on the spatio-temporal distrib…
Robotic manipulators navigating cluttered shelves or cabinets may find it challenging to avoid contact with obstacles. Indeed, rearranging obstacles may be necessary to access a target. Rather than planning explicit motions that place obstacles into a desired pose, we suggest allowing incidental con…
Our aim is to provide effective interaction with virtual objects, despite the lack of co-location of virtual and real-world contacts, while taking advantage of relatively large skin area and ease of mounting on the forearm. We performed two human participant studies to determine the effects of hapti
ReachBot is a new concept for planetary exploration, consisting of a small body and long, lightweight extending arms loaded primarily in tension. The arms are equipped with spined grippers for anchoring on rock surfaces. The design and testing of a planar prototype is presented here. Experiments wit…
Perceiving the environment through touch is important for robots to reach in cluttered environments, but devising a way to sense without disturbing objects is challenging. This work presents the design and modelling of whisker-inspired sensors that attach to the surface of a robot manipulator to sen…
Tactile sensing can improve end-effector control and grasp quality, especially for free-flying robots where target approach and alignment present particular challenges. However, many current tactile sensing technologies are not suitable for the harsh environment of space. We present a tactile sensor…
We present a highly conformable stretchable sensory skin made of soft components. The skin uses low pressure pneumatic taxels and stretchable channels to conduct pressure signals to off-board micro-electromechanical systems (MEMS) pressure sensors. The force sensing range captures down to 0.01 N and
We present a new gripper and exploration approach that uses a finger with very low reflected inertia for probing and then grasping objects. The finger employs a transparent transmission, resulting in a light touch when contact occurs. The finger elements are stiff and mounted on precise Cartesian ax
We present a design and fabrication method using low-cost materials for anew tactile sensor that is highly stretchable (up to 60%) and for which the signal is substantially unaffected by stretching, immersion in water, or electromagnetic noise. The sensor can be wrapped around the front, side and ba
As robots branch out from the manufacturing sector into the home, there is a pressing need for new technology that can operate in cluttered and unstructured human environments. Loading and unloading a dishwasher serves as a difficult representative challenge for in-home robots, and a new robotic end
We present a tactile sensor intended for manipulation by mobile robots, e.g., in the home. The surface consists of an array of small, rounded bumps or “nibs,” for reliable traction on objects like wet dishes. When the nibs contact a surface they deflect, and capacitive sensors measure the correspond
We present a lightweight, low power, and compliant miniature dielectric fluid transducer intended for haptic surface display. The actuator has a large strain and fast response without an external compressor. It consists of a thin oil-filled pouch with a 1.5 mm diameter opening covered with a silicon
We present a capacitive sensor suitable for a gripper that uses thin films of gecko-inspired adhesives. The sensor is fabricated directly on the films and measures the area over which the adhesive makes intimate contact. In experiments, a new underactuated gripper uses adhesive films to acquire and
A novel end-effector is presented for a large climbing robot. The gripping surfaces are covered with sharp spines to achieve a high shear stress on rocky surfaces. Soft, flexure-based joints and the natural compliance of a particle-jamming pad in the palm allow the end-effector to conform to a varie
We present a new rolling diaphragm actuator for transmitting forces in a teleoperated system. The initial application is for MR-guided biopsy procedures, providing accurate transmission of motions and forces between the fingertips of a physician and a biopsy needle being inserted into tissue. Desira
In robotics, high gear reductions are often required when using an electromagnetic motor to drive revolute joints, as in a humanoid robot. Strain wave gears (SWGs), also known as harmonic drives, are often used. However, these transmissions are relatively expensive and have a fixed gear ratio. Here,
Previous work has demonstrated the versatility of soft robotic grippers using simple control inputs. However, these grippers still face challenges in grasping large objects and in achieving high-strength grasps. This work investigates the combination of fluidic elastomer actuators and gecko-inspired
Active sensing provides a way to assess whether a thin film of gecko-inspired adhesive has made good contact with a surface. This knowledge is useful for applications like gripping objects in space where a failed grasp could lead to loss of the object. Our active sensing approach uses Lamb waves in
Augmented reality (AR) systems have been proposed for medical needle procedures as alternatives to restore the physician's natural perspective and head motion parallax that are lost when using standard imaging methods. AR systems have assumed a rigid needle, but in practice, a needle can experience
Effective handling of delicate objects remains a challenging problem in manufacturing. Instead of using a specialized gripper or control scheme, we present a solution involving gecko-inspired directional adhesives affixed to an industrial robot gripper and tactile sensor. The adhesives sustain large
Grasping and manipulation of biological tissue are crucial processes during Robot-Assisted Surgery (RAS). An intelligent system that aids surgeons in maintaining a reliable, atraumatic grasp on tissue, would allow them to focus on the clinical task, and potentially improve safety and performance. To
Free-flying robots have the potential to autonomously fulfill a wide range of tasks involving manipulation of objects in space. In this paper we study the design of a wrist mechanism for free-flying robots that are equipped with an adhesive gripper for attaching to objects and surfaces. The wrist an…
We present work on incipient slip sensing and recovery for controllable gecko-inspired adhesives. The approach is based on the relationship between changes in real contact area and maximum shear force. Using signals from an on-board tactile sensor, we detect the onset of adhesive failure and execute
We present a new palm design that features a dense array of micro-spines for the JPL Robosimian human-scale climbing robot. A linearly-constrained spine mechanism is introduced and analyzed using adhesion and stiffness models. This mechanism achieves a spine density of 19/cm2 and a mean adhesion of…
We explore the use of grippers with gecko-inspired adhesives for spacecraft docking and acquisition of tumbling objects in microgravity. Towards the goal of autonomous object manipulation in space, adhesive grippers mounted on planar free-floating platforms are shown to be tolerant of a broad range
We present the design and implementation of a miniature tactile sensing array for ground reaction force measurements in small legged robots. Dynamic ground pressure data from the sensors were collected using a small two-legged runner and used to train a support vector machine (SVM) terrain classifie
We present a simple statistical model to predict the maximum pulling force available from robot teams. The expected performance is a function of interactions between each robot and the ground (e.g., whether running or walking). We confirm the model with experiments involving impulsive bristlebots, s
To minimize weight and cost, it is sometimes desirable to power multiple functions with a single actuator. In this letter, we present a new mechanism for powering two degrees of freedom with a single motor. We introduce a method, termed dynamic response switching (DRS), in which the actuator can dri
Nearly all robotic grippers have one trait in common: they grasp objects with normal forces, either directly, or indirectly through friction. This method of grasping is effective for objects small enough for a given gripper to partially encompass. However, to grasp larger objects, significant grip f…
Perching on a vertical surface carries the risk of severe damage to the vehicle if the maneuver fails, especially if failure goes undetected. We present a detection method using an onboard 3-axis accelerometer to discriminate between perching success and failure. An analytical model was developed to…
As the number of rocket bodies and other debris in Earth's orbit increases, the need to capture and remove this space junk becomes essential to protect new satellites. A low cost solution may include gecko-inspired directional adhesives, which require almost no compressive preload to generate adhesi…
Pinching is an important capability for mobile robots handling small items or tools. Successful pinching requires force-closure and, in underwater applications, gentle suction flow at the fingertips can dramatically improve the handling of light objects by counteracting the negative effects of water…
Adhesion quality sensing is critical to the performance of any robot that utilizes gecko-inspired dry adhesives for climbing, perching, or grasping. We present a 3-axis tactile sensor designed for this application that demonstrates performance on par with a large commercial load cell while being com…
The ability to carry large payloads could greatly increase the applications of small, low cost climbing robots. We present a linear inchworm gait that uses a single powerful actuator to climb. To make this gait possible, we leveraged two new methods of achieving controllable, anisotropic adhesion (o…
The controllable adhesives used by insects to both carry large loads and move quickly despite their small scale inspires the μTug robot concept. These are small robots that can both move quickly and use controllable adhesion to apply interaction forces many times their body weight. The adhesives ena…