Robotic system for assembly and maintenance of lightweight reconfigurable structures
Robotics Automation and Control
Robotic system for assembly and maintenance of lightweight reconfigurable structures (TOP2-321)
Automated Reconfigurable Mission Adaptive Digital Assembly Systems (ARMADAS) - Hinged, alternating anchor-motion walking/crawling device for autonomous building with ultra-light, strong, and self-reprogrammable mechanical metamaterials
Overview
Missions to the moon and other planets will require large-scale infrastructure that would benefit from autonomous assembly by robots without on-site human intervention. Modular and reconfigurable structures, such as those built from lattice-based building blocks, are reusable and easy to manufacture. Furthermore, reconfigurable systems have the potential to outperform traditional, fixed infrastructure in applications that require high levels of flexibility in addition to structural strength and rigidity. NASA Ames Research Center has developed a novel and efficient mobile bipedal robot system to construct low-mass, high precision, and large-scale infrastructure. The mobile bipedal robot system is configured to carry, transfer, and place lattice-based modular unit cells, called voxels, to form a three-dimensional lattice structure. A team of mobile bipedal robots can autonomously unpack and assemble unit cells into functioning structures and systems. The technology provides an integrated system that enables large-scale surface and in-space structural assembly.
The Technology
To enable the goal of autonomous assembly of high performing structures, a robot system must be able to travel across a lattice structure in all dimensions, transport and align a unit cell module to the correct location and fasten the module to the existing structure. In this system, a team of multiple mobile bipedal robots work together to carry, transfer, and place 3D-lattice modules (e.g., cuboctahedron voxels) to form a 3D lattice structure. The team of mobile bipedal robots autonomously provide transportation, placement, unpacking, and assembly of voxel modules into functional structures and systems. As the team of mobile bipedal robots live and locomote on the 3D-lattice structure, they monitor health and performance, enabling repair and reconfiguration when needed. The mobile bipedal robots work together in different roles, for example, one as a cargo transport robot and the other as a crane robot. The cargo transport robot and the crane robot work together to move the voxels from one location to another. Each robot includes at least one electronic control module that receives commands from another robot or a central control system. A central control system implements a plan to control the motion sequences of the robots to maximize efficiency and to optimize the work required to completely assemble a structure. The plan is pre-computed or computed during implementation by the central control system or the robots themselves, according to algorithms that utilize the regularity of the lattice structure to simplify path planning, align robotic motions with minimal feedback, and minimize the number of the degrees of freedom required for the robots to locomote across and throughout the 3D-lattice structure and perform structural assembly.
Benefits
- Uses lightweight materials and components, reducing launch volume on space missions
- Builds structures that are scalable, precise, and reconfigurable
- Autonomous assembly of infrastructure using task-specific robots and discrete algorithms
- Enables voxel repair with mobile bipedal robots, reducing need to store and obtain spare parts
- Voxels structures are revisable by mobile bipedal robots
- Teams of mobile bipedal robots allows the prompt and efficient construction, assembly, and servicing of physical systems and infrastructure
Applications
- Adaptive infrastructure
- Space exploration
- Disaster response
- Robot Charging Station
- Self-powering Rail System
- Wall (shelter/blast/berm)
- Various space applications may include - Large aperture Rx/Tx instrumentation - Mega solar arrays - Nuclear propulsion - Star shades - Spacecraft shielding -Orbital infrastructure
- Terrestrial applications may include - Solar/ Communication Tower w/ Adaptive Footing (no surface prep) - Power infrastructure - Bridges and roads - Habitats - Garages -Landing pads - Transport infrastructure - Antennas - Scientific instrumentation
Technology Details
Robotics Automation and Control
TOP2-321
ARC-18774-1
ARC-18937-1
https://www.nasa.gov/directorates/spacetech/game_changing_development/projects/armadas
https://ieeexplore.ieee.org/document/10161263
https://www.science.org/doi/10.1126/scirobotics.adi2746
https://technology.nasa.gov/patent/TOP2-310
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The image below shows a storyboard of operations for how Assemblers might build a solar array. NASA has developed a hardware demo with communications between subsystems, backed up by detailed simulations of the kinematics and actuator dynamics.
Reversible Androgynous Mechanical Fastener
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Robonaut 2: Industrial Opportunities
NASA, GM, and Oceaneering approached the development of R2 from a dual use environment for both space and terrestrial application. NASA needed an astronaut assistant able to function in space and GM was looking for a robot that could function in an industrial setting. With this in mind, R2 was made with many capabilities that offer an enormous advantage in industrial environments. For example, the robot has the ability to retool and vary its tasks. Rather than a product moving from station to station on a conveyor with dozens of specialized robots performing unique tasks, R2 can handle several assembly steps at a single station, thereby reducing manufacturing floor space requirements and the need for multiple robots for the same activities. The robot can also be used in scenarios where dangerous chemicals, biological, or even nuclear materials are part of the manufacturing process.
R2 uses stereovision to locate human teammates or tools and a navigation system. The robot was also designed with special torsional springs and position feedback to control fine motor movements in the hands and arms. R2's hands and arms sense weight and pressure and stop when they come in contact with someone or something. These force sensing capabilities make R2 safe to work side-by-side with people on an assembly line, assisting them in ergonomically challenging tasks or working independently.
This NASA Technology is available for your company to license and develop into a commercial product. NASA does not manufacture products for commercial sale.
Robonaut 2: Logistics and Distribution
R2 was designed to work side-by-side with people and to be sensitive to its surroundings. The robot's advanced vision systems and recognition processing can quickly recognize a person in its path and take the appropriate action. If the robot comes into contact with a person or piece of equipment, it gives. There is no need to design specialized equipment for R2 because the robot has the ability to operate equipment and machines designed for humans, like hand-held power tools. R2 has the capability to improve the speed and accuracy of operations while maintaining sensitivity to its surroundings, making the robot prime for the logistics and distribution environment.
R2 was designed to handle unexpected objects coming into its path since it has to function in space where not everything is locked down. The robot has the ability to move in unconventional ways as compared to existing robots. Robonaut 1, an earlier version of R2, was integrated with a two-wheeled Segway personal transporter, giving it a range of motion. R2 has the capability of being integrated onto a two-wheeled base or a more rugged four-wheel base. An adaptable interface would enable R2 to integrate with other surface mobility systems.
This NASA Technology is available for your company to license and develop into a commercial product. NASA does not manufacture products for commercial sale.
Lunar Surface Manipulation System
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