Flora Robotica – Mixed Societies of Symbiotic Robot-Plant Bio-Hybrids

Besides the life-as-it-could-be driver of artificial life research there is also the concept of extending natural life by creating hybrids or mixed societies that are built from both natural and artificial components. In this paper, we motivate and present the research program of the project flora robotica. We present our concepts of control, hardware de-sign, modeling, and human interaction along with preliminary experiments. Our objective is to develop and to investigate closely linked symbiotic relationships between robots and natural plants and to explore the potentials of a plant-robot society able to produce archi-tectural artifacts and living spaces. These robot-plant bio-hybrids create synergies that allow for new functions of plants and robots. They also create novel design opportunities for an architecture that fuses the design and construction phase. The bio-hybrid is an example of mixed societies between ‘hard artificial and ‘wet natural life, which enables an interaction between natural and artificial ecologies. They form an embodied, self-organizing, and distributed cognitive system which is supposed to grow and develop over long periods of time resulting in the creation of meaningful architectural structures. A key idea is to assign equal roles to robots and plants in order to create a highly integrated, symbiotic system. Besides the gain of knowledge, this project has the objective to cre-ate a bio-hybrid system with a defined function and application – growing architectural artifacts

Stuructural Changes and Intra- and Extracellular Ion Movements in Motor Cells during Leaf Closure of Insectivorous Venus Flytrap

To examine the regulatory mechanism of leaf closure in the insectivorous plant Venus flytrap, light and electron microscope studies on the distribution of motor cells, the ultrastructure of those cells, and the intra- and extracellular movement of various ions during leaf closure were performed in a specified region near the midrib at the middle of the blade. Light microscope observation revealed that one or two well-arrayed hypodermal cell layers were present beneath the epidermis. In hypodermal and epidermal cells, during leaf closure, the cell volume measured by the montage method decreased significantly on the adaxial side and increased significantly on the abaxial side, indicating their major contribution as motor cells to leaf closure. Electron microscope observation showed that motor cells of hypodermal and epidermal cell layers contained electron-dense materials located along the inner surface of tonoplasts. On the adaxial side, electron-dense materials found as flattened sheets changed shape to numerous small globules during leaf closure. An inverse change in electron-dense materials in the structure was found on the abaxial side. Since the structural change of electrondense materials is correlated with the volume change of motor cells during leaf closure, they may play a significant role turgor variation in those cells. Quantitative X-ray microanalysis of cryosections showed that, during leaf closure, the concentration of K decreased significantly in the vacuolar electron-dense material, vacuolar lumen, and cell walls on the adaxial side, while it increased on the abaxial side. In the blade region near the midrib, K ions released from the vacuolar electron-dense material in the adaxial cells may cause the movement of water to the abaxial region, and eventually turgor movement by the swelling of abaxial motor cells. The reciprocal Ca movement between adaxial and abaxial motor cells during leaf closure indicates the possible role of Ca ions in regulating the turgor pressure.原

Effects of pre- and postharvest calcium supplementation on longevity of sunflower (Helianthus annuus cv. Superior Sunset)

The sunflower is one of the most important specialty cut flowers produced. Sunflowers have a short and variable postharvest longevity that is dependent upon cultivar. Research in postharvest physiology of cut flowers indicates that calcium (Ca) may be involved in delaying flower senescence by postponing cell membrane degradation. Cut flowers with intact cell membrane structure and function maintain their water balance and last longer. This study was developed to determine the effects of Ca supplementation on longevity of fresh cut sunflowers. The cultivar ‘Superior Sunset’ was used in this study; the sources of Ca were Ca(NO3)2, CaCl2 or a chelated Ca at 125 (low), 250 (medium), or 500 (high) mg/l amounts of Ca. The chelate minus Ca and sodium nitrate (NaNO3) were used as control treatments. Untreated flowers were included in all the experiments; means and standard errors were calculated for comparison with treatments. Ca was applied prior to harvest as a foliar spray or a weekly drench. Results indicated that the Ca treatments did not increase postharvest longevity of sunflower when treated preharvest; however, there was an increase in Ca concentration of stem tissue content compared to the untreated plants. Postharvest application of Ca chelate supplied as a 2-h pulse increased postharvest longevity of sunflower by up to 2 d compared to untreated flowers. Sunflowers treated with Ca also had a greater increase in fresh weight after 8 d in postharvest and improved water retention. Sunflowers treated with Ca had a greater concentration of the cation compared to the untreated flowers

From a Pinecone to Design of an Active Textile

Botanical nastic systems demonstrate non‐directional structural responses to stimuli such as pressure, light, chemicals or temperature; hygronasty refers to systems that respond specifically to moisture. Many seed dispersal mechanisms such as wheat awns, legume pods, spruce and pinecones fall within this classification. The variety of behaviours varies greatly from opening and closing to self‐digging, but the mechanism is based on differential hygroscopic swelling between two adjacent areas of tissue. We describe the application of hygronastic principles specifically within the framework of textiles via the lens of structural hierarchy. Two novel prototypes are presented. One is designed to increase its permeability to airflow in damp conditions and reduce permeability in the dry by 25–30%, a counterintuitive property compared to conventional cotton, wool and rayon textiles that decrease their permeability to airflow as their moisture content increases. The second prototype describes the design and development of a hygroscopic shape changing fibre capable of reducing its length in damp conditions by 40% when compared with dry