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The new SMC substrate has four components: a shape memory polymer separately developed at NASA Langley; a stack of thin-ply carbon fiber sheets; a custom heater and heat spreader between the SMC layers; and integrated sensors (temperature and strain). The shape memory polymer allows the as-fabricated substrate to be programmed into a temporary shape through applied force and internal heating. In the programmed shape, the deformed structure is in a frozen state remaining dormant without external constraints. Upon heating once more, the substrate will return slowly (several to tens of seconds) to the original shape (shown below). The thin carbon fiber laminate and in situ heating solve three major pitfalls of shape memory polymers: low actuation forces, low stiffness and strength limiting use as structural components, and relatively poor heat transfer. The key benefit of the technology is enabling efficient actuation and control of the structure while being a structural component in the load path. Once the SMC substrate is heated and releases its frozen strain energy to return to its original shape, it cools down and rigidizes into a standard polymer composite part. Entire structures can be fabricated from the SMC or it can be a component in the system used for moving between stowed and deployed states (example on the right). These capabilities enable many uses for the technology in-space and terrestrially.

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.