Constructing living buildings: a review of relevant technologies for a novel application of biohybrid robotics

Biohybrid robotics takes an engineering approach to the expansion and exploitation of biological behaviours for application to automated tasks. Here, we identify the construction of living buildings and infrastructure as a high-potential application domain for biohybrid robotics, and review technological advances relevant to its future development. Construction, civil infrastructure maintenance and building occupancy in the last decades have comprised a major portion of economic production, energy consumption and carbon emissions. Integrating biological organisms into automated construction tasks and permanent building components therefore has high potential for impact. Live materials can provide several advantages over standard synthetic construction materials, including self-repair of damage, increase rather than degradation of structural performance over time, resilience to corrosive environments, support of biodiversity, and mitigation of urban heat islands. Here, we review relevant technologies, which are currently disparate. They span robotics, self-organizing systems, artificial life, construction automation, structural engineering, architecture, bioengineering, biomaterials, and molecular and cellular biology. In these disciplines, developments relevant to biohybrid construction and living buildings are in the early stages, and typically are not exchanged between disciplines. We, therefore, consider this review useful to the future development of biohybrid engineering for this highly interdisciplinary application.publishe

Branch-pipe: Improving graph skeletonization around branch points in 3D point clouds

Modern plant phenotyping requires tools that are robust to noise and missing data, while being able to efficiently process large numbers of plants. Here, we studied the skeletonization of plant architectures from 3D point clouds, which is critical for many downstream tasks, including analyses of plant shape, morphology, and branching angles. Specifically, we developed an algorithm to improve skeletonization at branch points (forks) by leveraging the geometric properties of cylinders around branch points. We tested this algorithm on a diverse set of high-resolution 3D point clouds of tomato and tobacco plants, grown in five environments and across multiple developmental timepoints. Compared to existing methods for 3D skeletonization, our method efficiently and more accurately estimated branching angles even in areas with noisy, missing, or non-uniformly sampled data. Our method is also applicable to inorganic datasets, such as scans of industrial pipes or urban scenes containing networks of complex cylindrical shapes

TLS点群データを用いた3D樹木モデルの構築と応用

2019東京農業大

Measuring and Modeling the Structure of Coniferous Trees with Point Clouds Data

Coniferous trees are a major North American crop that has been intensively managed for its commercial value, while also serving as critical habitat for abundant wildlife and as carbon sinks. Having diverse functions, North American temperate coniferous forests have become a research hotspot for numerous scientific studies aiming to integrate ecological and economic objectives, such as examining the contribution of the conifer crown architecture to long-term forest management schemes. Point clouds have become an important source of forest inventory data and forest ecological studies, as provide accurate and comprehensive estimates of many structural variables. The present thesis aims to improve the understanding of conifer crown structure by estimating crown variables and developing stem and crown models using point clouds derived from images or laser scanning. The utilizations of point clouds were tested on loblolly pine plantations and mature Douglas-fir trees in a natural stand. Various types of 3D models were constructed for tree stems and branch attributes using point clouds. The 3D models provide direct volume estimates, as well as estimates of tree structural variables including tree height, stem diameter, branch basal diameter, length, insertion angle, and azimuth. The variable extractions were executed with semi-automatic methods, which combine human interpretation with an automatic estimation algorithm. The accuracy and reliability of point-clouds-based estimates were assessed with ground measurements and estimates from existing equations through simulations. Stem taper equations were developed using point-clouds-based stem diameter estimates. Nonlinear models of branch variables, as well as systematic crown models, were developed using lidar-based estimates by considering neighboring competition effects. The results demonstrate the reliability and efficiency of using point clouds data as alternatives or complements to traditional fieldwork. Stem and branch variables estimated nondestructively from lidar and photogrammetry point clouds agreed with ground measurements and fit in the range of observations from existing equations. Workflows developed and presented in this thesis can be employed by forestry practitioners and researchers to acquire fast and accurate tree structural variables, while models of stem and branch attributes can guide forest inventory and silvicultural practices as well as advance ecological research

Data-Driven Synthetic Modeling of Trees

In this paper, we develop a data-driven technique to model trees from a single laser scan. A multi-layer representation of the tree structure is proposed to guide the modeling process. In this process, a marching cylinder algorithm is first developed to construct visible branches from the laser scan data. Three levels of crown feature points are then extracted from the scan data to synthesize three layers of non-visible branches. Based on the hierarchical particle flow technique, the branch synthesis method has the advantage of producing visually convincing tree models that are consistent with scan data. User intervention is extremely limited. The robustness of this technique has been validated on both conifer and broadleaf trees