Space Suit RoboGlove (SSRG)

Originally developed by NASA and GM, the Robo-Glove technology was a spinoff of the Robonaut 2 (R2), the first humanoid robot in space. This wearable device allows the user to tightly grip tools and other items for longer periods of time without experiencing muscle discomfort or strain. An astronaut working in a pressurized suit outside the space station or an assembly operator in a factory might need to use 15 to 20 lbs of force to hold a tool during an operation. Use of the Robo-Glove, however, would potentially reduce the applied force to only 5 to 10 lbs. The Robo-Glove is a self-contained unit, essentially a robot on your hand, with actuators embedded into the glove that provide grasping support to human fingers. The pressure sensors, similar to the sensors that give R2 its sense of touch, are incorporated into the fingertips of the glove to detect when the user is grasping an object. When the user grasps the object, the synthetic tendons automatically retract, pulling the fingers into a gripping position and holding them there until the sensor is released by releasing the object. The current prototype weighs around two pounds, including control electronics and a small display for programming and diagnostics. A lithium-ion battery, such as one for power tools, is used to power the system and is worn separately on the belt.

Visual Perception System: Key to enabling humanoid robotics to perform dexterous tasks, R2’s visual perception system (U.S. Patent No. 8,244,402) – comprised of machine vision cameras, processors, and novel algorithms – allows robots to find, track, and measure objects automatically in their field of view. Tendon Tension Sensor: Unique tendon tensions sensors (U.S. Patent Nos. 8,371,177 & 8,056,423) are embedded in R2’s palms to enable granular force control of the fingers via a redundant network of tendons. R2’s tendons are coupled to, and used to actuate, the robot’s finger joints. Thus, tendon tension measurements provided by the sensor allow for the external loads experienced by its robotic fingers to be derived. Tactile System: R2’s hands feature an innovative tactile system that grant the robot a sense of touch (e.g., measurement of external contact forces, shear force, and slippage of objects held in the hand) – an important requirement for robots designed to perform complex tasks in an automated fashion. The tactile system is enabled by novel six degree of freedom (DoF) force torque sensors (U.S. Patent No. 7,784,363), which are integrated into the fingers at each phalange (14 per hand). A calibration system (U.S. Patent No. 8,265,792) ensures the sensors maintain high accuracy throughout operation. Contact State Estimation: A contact state estimation sensor (U.S. Patent No. 8,280,837), based on the use of a particle filter, enables R2 to perceive the location, orientation, and shape of objects when in contact with the robot’s hands (i.e., tracks hand-object state). The contact state estimation system leverages a novel motion model, which characterizes the motion of a robotic hand as it moves relative to an object of interest. Series Elastic Actuator (SEA) Sensing: R2’s SEAs achieve fine torque sensing at each of its joints without sacrificing strength or payload capacity. The robot uses two 19-bit absolute angular position sensors, calibrated using a novel technique (U.S. Patent No. 8,250,901), to measure the deflection of each spring in real time.

The Foot Pedal Controller enables an operator of a spacecraft, aircraft, or watercraft, or a simulation of one in a video game, to control all translational and rotational movement using two foot pedals. This novel technology allows control across all six degrees of freedom, unlike any technology on the market. The components of the technology are a support structure, a left foot pedal, a right foot pedal, and supporting electronics. The Foot Pedal Controller is intuitive, easy to learn, and has ergonomic features that accommodate and stabilize the operator's feet. A working prototype is available to demonstrate key technology features to potential licensees. The Foot Pedal Controller technology could be used in designs for the flight deck of the future, video game controls, drone operations and flight simulators. This technology can be useful in any application where it is preferred or desirable to use the feet to control motion rather than using the hands. A potential market could be foot control of equipment by people with arm or hand disabilities. A unique aspect of the innovation is the consideration of natural foot mechanics in the design and placement of the sensors and actuators to reduce operator fatigue. The axes of rotation of the Controller align with the joints of the foot so the foot moves naturally to control the movement of the craft. NASA seeks collaborations with companies interested in licensing and partnering to further develop and commercialize the technology.

The SRTS enables measurement of position, velocity, and torque of a rotating system (e.g., actuator, motor, crankshaft, rotor, etc.) using two optical sensors and a single, custom-designed split-ring rather than the standard dual-ringed systems commonly used for similar applications. The split-ring is comprised of two structural arcs positioned in a concentric, coplanar relationship, wherein each arc is attached to a component capable of rotation (e.g., a lower leg and upper leg, where the SRTS acts as a knee). The two arcs contain indications or codes on their outer surfaces that are read by the optical sensors to determine the relative deflection of the structural arcs as they rotate. The SRTS configuration discussed above is limited to 180-degree applications. The addition of a third structural arc and a third optical reader, however, would enable 360-degree functionality. Tests have shown the SRTS has a high degree of tolerance to temperature differences and provides higher resolution measurements than competing technologies.

Technologies for Safe Workspace Control of Humanoid Robots: Safety is critical in scenarios where humans (e.g., factory workers or astronauts) are working in proximity to, or interacting with, R2. Methods for applying workspace limitations in velocity-controlled robotic mechanisms (U.S. Patent No. 8,676,382) and force or impedance-controlled robots (U.S. Patent No. 8,483,877) help to ensure such safety. Autonomous Control Systems for Humanoid Robotics: A multiple priority operation space impedance control system (U.S. Patent No. 8,170,718) provides arm control, including programmable Cartesian stiffness. An interactive robot control architecture (U.S. Patent Nos. 8,364,314, and 8,260,460, and 8,706,299), including a simple GUI, provides an interactive development and work environment that integrates sensor data and feedback generated by R2. An additional system selects and controls appropriate manipulators to perform grasping operations (U.S. Patent No. 8,483,882). Humanoid Robotic Health Management System: A diagnostics, prognostics, and health management system for human robotics (U.S. Patent No. 8,369,992) operates at all hardware and software levels of the robotic system, enabling system-wide observability, controllability, maintainability, scalability, and extensibility. Electromagnetic Motor Braking: Electromagnetic fail-safe brakes (U.S. Patent No. 8,067,909) allow for selective, reliable braking of robotic motors (e.g., brushless DC motors) to ensure safe and effective operation. Highly Durable Connector Pin: To address the high failure rate of connectors in robotic systems with flexible members, a highly durable connector pin (U.S. Patent No. 8,033,876) was developed. The pin increases durability of connectors that are frequently flexed – a condition that causes deformation and compromises connectivity.