Workpackage Organisation

The workpackages of the scientific programme are grouped into three thematic sets: Shape and Trajectory DataAcoustic Simulation, and Biomimetic Engineering. There also exists a Theme 0: Management.

Theme 1: Shape and Trajectory Data

The first requirement for realistic modelling of the relationship of biosonar skills to morphology, call structure and behaviour is detailed data on morphology and behaviour of the selected bat species. Acquiring such data is the objective of Theme 1.

Workpackages in Theme 1:

1.1    Acquisition of Static Head, Pinna, and Noseleaf Shapes
1.2    Acquisition of Varying Shape Data from Behaving Bats
1.3    Compilation of 3D Trajectory-registered Data
The three workpackages from this Theme proceed largely sequentially. Shape models devised in WP 1.1 feed into the novel modelling and data interpretation work of WP 1.2. The captured shape data is registered with trajectory data in WP 1.3, which also takes bat acoustic and behavioural data from WP 2.2 and reconstructed calls from WP 2.3 and integrates them in the complete data set.

Theme 2: Acoustic Simulation

Given the static and dynamic shape data, collected as part of the Theme 1 activities, it is then possible to compute the beam-forming effect of the bat head morphology. The functional models derived from this study can then be used to implement the biomimetic sonar system required by the robotic demonstrator systems that are the subject of Theme 3. This theme is subdivided into four workpackages that address the key problems which must be solved before the full acoustic properties of the bat’s sound generation and reception subsystems can be understood and reproduced.

Workpackages in Theme 2:

2.1    Acoustic Modelling of Static and Deforming Sound Reflecting Structures
2.2    Capture and Analysis of Bat Calls sorted by Task
2.3    Inverse Reconstruction of Bat Calls
2.4    Dynamic Directivity Shaping
Workpackage inter-dependencies in this Theme are as follows: WP 2.4 requires input from WP 2.1 and 2.2, which determine the necessary degrees of controllability the emulation hardware must offer. WP 2.3 depends on WP 2.1 for directivity simulations and WP 2.2 for call recordings. WP 2.1–2.3 feed data to WP 1.3 for collection in the data set that underpins work on computational modelling in Theme 3.

Theme 3: Biomimetic Engineering

Theme 3 is the main focus of the project. Using a classical biomimetic approach of careful analysis of specific biological systems, in collaboration with expert biologists integrated with computational modelling and engineering implementation, we shall construct two working model sonar systems mimicking how the chosen bat species may realise their perceptual abilities. The first model will focus on prey detection, location and capture behaviours of Micronycteris microtis, implemented using a robot arm. The second will focus on detection, location and capture behaviours of the trawling bats, imitating their different morphology (e.g. with/without nose-leaf, nasal versus oral emission) and signal characteristics principally focussed on Myotis daubentonii, and implemented using a mobile robot. In each case, a spiral methodology of `analyse, design, build, and evaluate’ will be employed. We anticipate making at least two cycles of the spiral. The data and techniques from Themes 1 and 2 will underpin this work.

Workpackages in Theme 3:

3.1    Bat Capture, Training and Experimentation
3.2    Modelling of Relevant Acoustic Behaviours
3.3    Modelling of Relevant Motor Behaviours
3.4    Implementation of Biomimetic Models onto Robotic Platforms
3.5    Characterisation and Evaluation of Biomimetic Models
The dependencies among these workpackages are as follows. WP 3.1 underpins all the bat experimentation planned for the project; it starts immediately and runs through the project in parallel with other activities. WP 3.2 and 3.3 comprise the analysis phase of the biomimetic approach, while WP 3.4 is implementation and WP 3.5 evaluation: they occur in sequence. We anticipate completing two cycles of the spiral design process so once evaluation of the first models is complete in WP 3.5, the knowledge gained will be fed back to WP 3.2 and 3.3 for model revision.