Insulting words: They are animals!

As Chapman & Huffman state, creating divisive human categories has rationalized atrocities committed against the “other.” Labeling neighboring warring villagers as “animals” is considered a despicable insult. Yet contemporary scientific views of many animals grant them thinking and conscious faculties, and the capacity for impressive achievements, many unattainable by humans. Robots, too, can accomplish many similar feats. But the essential reason we must protect animals is not because of their admirable abilities, but their capacity for consciousness, for suffering. Robots are not conscious. Participants in the human-animal debate should not complain about changing criteria for determining human uniqueness. New and refined hypothesis-making is the stuff of science

Printing-while-moving: a new paradigm for large-scale robotic 3D Printing

Building and Construction have recently become an exciting application ground for robotics. In particular, rapid progress in materials formulation and in robotics technology has made robotic 3D Printing of concrete a promising technique for in-situ construction. Yet, scalability remains an important hurdle to widespread adoption: the printing systems (gantry- based or arm-based) are often much larger than the structure to be printed, hence cumbersome. Recently, a mobile printing system - a manipulator mounted on a mobile base - was proposed to alleviate this issue: such a system, by moving its base, can potentially print a structure larger than itself. However, the proposed system could only print while being stationary, imposing thereby a limit on the size of structures that can be printed in a single take. Here, we develop a system that implements the printing-while-moving paradigm, which enables printing single-piece structures of arbitrary sizes with a single robot. This development requires solving motion planning, localization, and motion control problems that are specific to mobile 3D Printing. We report our framework to address those problems, and demonstrate, for the first time, a printing-while-moving experiment, wherein a 210 cm x 45 cm x 10 cm concrete structure is printed by a robot arm that has a reach of 87 cm.Comment: 6 pages, 7 figur

Cement-fibre composites for additive building manufacturing

The fused deposition principal of additive manufacturing (AM) involves the deposition of a material one layer at a time allowing the creation of an object from a 3D digital design. The associated reduction in the amount of waste material produced offers benefits and over the last decade, investigations have been carried out using cementitious materials for AM within the construction industry. Central to the profile of the technology increasing within the industry is the development of a suitable cementitious material which may be deposited without formwork. Research currently consists of ground-based gantry, or robotic arm methods which can be single or multi-agent. This paper presents the development of fibrous cementitious mortars and pastes suitablefor a miniaturised deposition system designed for use in a multi-agent AM approach. Synthetic polyvinyl alcohol (PVA), aramid and kevlar fibres along with natural fibres from the banana plant were investigated to evaluate contributions to the workability, buildability, mechanical strength and failure mechanisms of the cementitious composite material. The addition of fibres to a cementitious matrix results in compressive and flexural strength increases and transforms the method of failure from brittle to ductile. Results suggest PVA and kevlar fibres are suitable for a composite cementitious material with optimised rheology specifically designed for a multi-agent, miniaturised deposition approach for AM

Cement-fibre composites for additive building manufacturing

The fused deposition principal of additive manufacturing (AM) involves the deposition of a material one layer at a time allowing the creation of an object from a 3D digital design. The associated reduction in the amount of waste material produced offers benefits and over the last decade, investigations have been carried out using cementitious materials for AM within the construction industry. Central to the profile of the technology increasing within the industry is the development of a suitable cementitious material which may be deposited without formwork. Research currently consists of ground-based gantry, or robotic arm methods which can be single or multi-agent. This paper presents the development of fibrous cementitious mortars and pastes suitablefor a miniaturised deposition system designed for use in a multi-agent AM approach. Synthetic polyvinyl alcohol (PVA), aramid and kevlar fibres along with natural fibres from the banana plant were investigated to evaluate contributions to the workability, buildability, mechanical strength and failure mechanisms of the cementitious composite material. The addition of fibres to a cementitious matrix results in compressive and flexural strength increases and transforms the method of failure from brittle to ductile. Results suggest PVA and kevlar fibres are suitable for a composite cementitious material with optimised rheology specifically designed for a multi-agent, miniaturised deposition approach for AM

Fibrous cementitious material development for additive building manufacturing.

Additive Manufacturing (AM) in the construction industry is still in a relative state of infancy. Research has focused on heavy, ground based methods, with the building envelope determined by the dimensions of the deposition system. By comparison, the approach of using robots is not geometrically restricted but requires a degree of miniaturisation to the deposition process. Many studies utilise the AM principal of fused deposition modelling (FDM), which creates an object by extruding a suitably viscous material through a nozzle and depositing one layer at a time. Crucial to the development of cementitious materials for additive building manufacturing (ABM) without formwork, is the material possessing both workability and buildability, and appropriately balancing the contrasting requirements of these properties. Cementitious materialsare typically brittle, requiring reinforcement to provide tensile and flexural capabilities. Reinforcing steel bars are not naturally compatible with ABM and chopped fibres are considered as a viable alternative. This paper investigates the development of a fibrous cementitious mortar suitable for use with a miniaturised deposition system based upon the FDM principal. Three types of fibres – polypropylene, alkali-resistant glass and polyvinyl alcohol (PVA) - were investigated to assess suitability for a miniaturised ABM deposition method and contributions to the mechanical strength of a mortar. PVA fibres provided the best buildability and increased flexural strength, with the appropriate quantity contained in mixes being informed by the degree of detrimental impact upon workability

Fibrous cementitious material development for additive building manufacturing.

Additive Manufacturing (AM) in the construction industry is still in a relative state of infancy. Research has focused on heavy, ground based methods, with the building envelope determined by the dimensions of the deposition system. By comparison, the approach of using robots is not geometrically restricted but requires a degree of miniaturisation to the deposition process. Many studies utilise the AM principal of fused deposition modelling (FDM), which creates an object by extruding a suitably viscous material through a nozzle and depositing one layer at a time. Crucial to the development of cementitious materials for additive building manufacturing (ABM) without formwork, is the material possessing both workability and buildability, and appropriately balancing the contrasting requirements of these properties. Cementitious materialsare typically brittle, requiring reinforcement to provide tensile and flexural capabilities. Reinforcing steel bars are not naturally compatible with ABM and chopped fibres are considered as a viable alternative. This paper investigates the development of a fibrous cementitious mortar suitable for use with a miniaturised deposition system based upon the FDM principal. Three types of fibres – polypropylene, alkali-resistant glass and polyvinyl alcohol (PVA) - were investigated to assess suitability for a miniaturised ABM deposition method and contributions to the mechanical strength of a mortar. PVA fibres provided the best buildability and increased flexural strength, with the appropriate quantity contained in mixes being informed by the degree of detrimental impact upon workability

Design to Robotic Assembly: An Exploration in Stacking

The Design-to-Robotic-Assembly project presented in this paper showcases an integrative approach for stacking architectural elements with varied sizes in multiple directions. Several processes of parametrization, structural analysis, and robotic assembly are algorithmically integrated into a Design-to-Robotic-Production method. This method is informed by the systematic control of density, dimensionality, and directionality of the elements while taking environmental, functional, and structural requirements into consideration. It is tested by building a one-to-one prototype, which is presented and discussed in the paper with respect to the development and implementation of the computational design workflow coupled with robotic kinematic simulation that is enabling the materialization of a multidirectional and multidimensional assembly system

Task-Consistent Path Planning for Mobile 3D Printing

In this paper, we explore the problem of task-consistent path planning for printing-in-motion via Mobile Manipulators (MM). MM offer a potentially unlimited planar workspace and flexibility for print operations. However, most existing methods have only mobility to relocate an arm which then prints while stationary. In this paper we present a new fully autonomous path planning approach for mobile material deposition. We use a modified version of Rapidly-exploring Random Tree Star (RRT*) algorithm, which is informed by a constrained Inverse Reachability Map (IRM) to ensure task consistency. Collision avoidance and end-effector reachability are respected in our approach. Our method also detects when a print path cannot be completed in a single execution. In this case it will decompose the path into several segments and reposition the base accordingly