Airborne chemical sensing with mobile robots

Airborne chemical sensing with mobile robots has been an active research areasince the beginning of the 1990s. This article presents a review of research work in this field,including gas distribution mapping, trail guidance, and the different subtasks of gas sourcelocalisation. Due to the difficulty of modelling gas distribution in a real world environmentwith currently available simulation techniques, we focus largely on experimental work and donot consider publications that are purely based on simulations

Perception and Behavior of InsBot : Robot-Animal Interaction Issues

This paper describes the hardware and behavior implementation of a miniature robot, in size of a match box, that is able to interact with cockroaches. The robot is equipped with two micro-processors dedicated to hardware processing and behavior generation. It is also equipped with 12 infra-red proximity sensors, 2 light sensors, a linear camera and a battery that allows 3 hours autonomy. The robot can discriminate cockroaches, other robots, environment boundaries and shelters. It has also three means of communication: a wireless module for monitoring and logging, an IR remote receiver for fast supervision of biological experiment and a simple local communication protocol via infrared proximity sensors to detect robots in short range

Human Control of Simulated Modular Soft Robots May Predict the Performance of Optimized AI-Based Controllers

Robots with a modular body permit a wide range of physical configurations, which can be obtained by arranging the composing modules differently. While this freedom makes modular robots capable of performing different tasks, finding the optimal physical configuration for a given task is not trivial. In fact, practitioners attempt to jointly optimize the body and the controller of the robot for a given task, but the result is not always satisfactory. More broadly, it is not clear what factors make a physical configuration more or less successful. In this paper, we aim to fill this gap and verify if humans can be predictive with respect to the performance of an optimized controller for a given robot body. We consider the case of Voxel-based Soft Robots (VSRs), whose rich dynamic induced by the softness of the modules makes the body particularly relevant for the robot ability to perform a task. We instantiate a number of (simulated) VSR bodies, differing in shape and actuation mechanism, and let a panel of humans control them, by means of online interaction with the simulator, while performing the task of locomotion. We use the same bodies with controllers obtained with evolutionary optimization, for the same task. We compare the ranking of human- and optimized AI-based VSRs, finding them very similar. We believe that our results strengthen the hypothesis that intrinsic factors in the body of modular robots determine their success

Identification of biogenic volatile organic compounds for improved border biosecurity

Effective border biosecurity is a high priority in New Zealand. A fragile and unique natural ecosystem combined with multiple crop systems, which contribute substantially to the New Zealand economy, make it essential to prevent the establishment of invasive pests. Trade globalisation and increasing tourism have facilitated human-assisted movement of invasive invertebrates, creating a need to improve pest detection in import pathways and at the border. The following works explore a potential new biosecurity inspection and monitoring concept, whereby unwanted, invasive insects may be detected by the biogenic volatile organic compounds (VOCs) they release within contained spaces, such a ship containers. The brown marmorated stink bug, Halyomorpha halys Stål, is an agricultural and urban pest that has become widely established as an invasive species of major concern in the USA and across Europe. This species forms large aggregations when entering diapause, and it is often these aggregations that are found by officials conducting inspections of internationally shipped freight. Stink bug species are known to emit defensive odours, making H. halys a suitable candidate as model species for this study. Undisturbed aggregations of diapausing H. halys were found to emit tridecane and (E)-2-decenal. Mechanical agitation of diapausing H. halys was used to induce emissions of defensive odours, and the full VOC profile was confirmed through GC-MS analysis as: tridecane (41.7 ± 11.8 µg per bug), (E)-2-decenal (18.2 ± 4.2 µg), 4-oxo-(E)-2-hexenal (15.8 ± 6.3 µg), and dodecane (1.5 ± 0.6 µg). Testing the role of conspecific bugs on VOC release, it was found that H. halys required the presence of another bug as well as mechanical agitation to elicit a defensive odour response. From this, the effect of conspecific defence compounds were individually tested on single H. halys. One component, 4-oxo-(E)-2-hexenal, was found to cause individual bugs to both move further distances after exposure, and also release their own defensive odour. Thus, the agitation of aggregations, as it might occur during freight shipping, could facilitate an amplification effect for release of odours; were one bug to emit defensive VOCs in an aggregation, more would be likely to emit. This may increase the likelihood of detection of these VOCs within an enclosed space such as shipping containers. Experiments were performed to simulate the effects of two variables introduced by the act of shipping, ship movement and journey temperature fluctuations, upon aggregations of diapausing H. halys. Aggregations exposed to simulated shipping movement, using a 6-axis VS-6577G-B Denso robot arm, were not found to be any more likely to release VOCs than aggregations which remained stationary, nor did it cause any bugs to become mobile. Simulated temperature changes as they would be experienced during a voyage over 26 days from a port in the north-east USA to New Zealand were found to have a significant effect on the mobility of H. halys. However, towards the end of the simulated voyage, most H. halys died, probably from a lack of food or moisture in the shipping scenario. The high mortality observed in these aggregations prompted the collection of headspace samples from dead H. halys over the same time period and experiencing the same temperatures. This revealed that dead and decaying H. halys release the full VOC profile of tridecane, (E)-2-decenal, 4-oxo-(E)-2-hexenal, and dodecane over three weeks, although in smaller quantities than when actively releasing defensive odours. Theoretical calculations showed that the GC-MS analytical method combined with active sampling volatile collection traps was not sensitive enough to detect volatiles released by aggregations of living, dead, or combined H. halys within a 20 foot (38,000 l) shipping container. However, there are more sensitive technologies available which can detect VOCs to the parts per trillion level, which would be capable of detecting the expected VOCs concentrations associated with the presence of H. halys in shipping containers

Simple individual behavioural rules for improving the collective behaviours of robot swarms

Swarm robotics is an ongoing area of research that is expected to revolutionise various real-world domains such as agriculture and space exploration. Swarm robotics systems are composed of a large number of simple and autonomous robots. Each robot locally interacts with other robots and with the environment following a set of behavioural rules. These individual interactions enable the swarm to exhibit interesting collective behaviours and to accomplish specific tasks. The main challenge in designing robot swarms is to determine the behavioural rules that each robot should follow so that the swarm as a whole can perform the desired task. The performance of robot swarms in a given task depends on the designer's choice of appropriate individual behavioural rules. In this thesis, we investigate simple individual behavioural rules for improving the performance of robot swarms in two major tasks. Using simple behavioural rules makes the designed solutions possibly usable with simpler platforms such as micro- and nanorobots. The first task we address is known as the best-of-n decision problem where the swarm is required to select the best option among n available alternatives. Solving the best-of-n decision problem is considered to be a fundamental cognitive skill for robot swarms as it influences the swarm's success in other tasks. In this thesis, we introduce individual behavioural rules to improve the performance of robot swarms in the best-of-n problem. Through these rules, robots vary their interaction strength over time in a decentralised fashion to balance the acquisition and the dissemination of information. The proposed behavioural rules allow swarms of simple noisy robots with constrained communication to limit the effect of individual errors and make highly accurate collective decisions in a predictable time. In some scenarios where the best option changes over time, the swarm is required to switch its decision accordingly. In this thesis, we introduce individual behavioural rules through which the robots process new information and discard outdated beliefs. These behavioural rules enable robot swarms to adapt their decisions to various environmental changes, including the appearance of better choices or the disappearance of the current swarm's choice. Our analysis shows that relying on local communication is more favourable for achieving adaptation. This result highlights the benefit of the local sensing and communication characterising biological and artificial swarms. The second task we address in this thesis is the collective resource collection task. In this task, the robots are asked to retrieve objects that are clustered at unknown locations in the environment. We address this task because of its numerous potential real-world applications. In many of these applications, the objects to collect are assigned different importance or value. In this thesis, we introduce a bio-inspired individual behaviour that allows robot swarms to perform quality-based resource collection. Similarly to foraging ants, in our proposed behaviour, the robots coordinate their collection efforts by laying and sensing virtual pheromone trails. The use of pheromone trails offers an advantageous implementation of the memory and communication capabilities necessary for the efficient collection of clustered objects. The proposed behaviour allows robot swarms to satisfy various collection objectives and achieve an optimal resource collection behaviour in the case of relatively small swarms. In this thesis, we analyse swarm robotics systems using both minimalistic tools such as stochastic and multi-agent simulations, and more advanced tools such as physics-based simulations and real robot experiments. Using these tools, we demonstrate the effectiveness of the proposed individual behavioural rules in improving the performance of robot swarms in the addressed tasks. The results we present in this thesis are of potential interest to both engineers designing robot swarms, and biologists investigating the behavioural rules followed by individuals in living collective organisms

Chasing Flies: The use of wingbeat frequency as a communication cue in Calyptrate Flies (Diptera: Calyptratae)

The incidental sound produced by the oscillation of insect wings during flight provides an opportunity for species identification. Calyptrate flies include some of the fastest and most agile flying insects, capable of rapid changes in direction and the fast pursuit of conspecifics. This flight pattern makes the continuous and close recording of their wingbeat frequency difficult and limited to confined specimens. Advances in sound editor and analysis software, however, have made it possible to isolate low amplitude sounds using noise reduction and pitch detection algorithms. To explore differences in wingbeat frequency between genera and sex, 40 specimens of three-day old Sarcophaga crassipalpis, Lucilia sericata, Calliphora dubia, and Musca vetustissima were individually recorded in free flight in a temperature-controlled room. Results showed significant differences in wingbeat frequency between the four species and intersexual differences for each species. Discriminant analysis classifying the three carrion flies resulted in 77.5% classified correctly overall, with the correct classification of 82.5% of S. crassipalpis, 60% of C. dubia, and 90% of L. sericata, when both mean wingbeat frequency and sex were included. Intersexual differences were further demonstrated by male flies showing significantly higher variability than females in three of the species. These observed intergeneric and intersexual differences in wingbeat frequency start the discussion on the use of the metric as a communication signal by this taxon. The success of the methodology demonstrated differences at the genus level and encourages the recording of additional species and the use of wingbeat frequency as an identification tool for these flies