Sonar is an important sensory modality for engineers as well as in nature. In engineering, sonar is the dominating modality for underwater sensing. In nature, biosonar is likely to have been a central factor behind the unprecedented evolutionary success of bats, a highly diverse group that accounts for over 20% of all mammal species. However, it remains unclear to what extent engineered and bio...

This paper describes how fuzzy control can be applied to a sonar-based mobile robot. Behavior-based fuzzy control for HelpMate behaviors was designed using sonar sensors. The fuzzy controller provides a mechanism for combining sensor data from all sonar sensors which present di®erent information. The behavior-based approach is implemented as an individual high priority behavior. The highest lev...

A sonar system is presented that relies on scanning a single ultrasonic transducer and measuring echo amplitude and arrival times. Bearing angles to targets are estimated far more accurately than the transducer beamwidth as obtained with conventional sonar rings based on the Polaroid ranging module. A Gaussian beam characteristic is fitted using least squares to the amplitudes of corresponding ...

The question of how beaked whales are affected by naval sonar is important for the US Navy as information is required for accurate environmental assessments. A number of recent studies have reported behavioral responses of a small number of beaked whales to experimentally-presented sonar signals (Tyack et al., 2011; DeRuiter et al., 2013; Stimpert et al., 2014, Miller et al., 2015). These studi...

This work describes techniques using sonar sensors for environmental feature detection and identiication. By detecting common features in indoor environments and using them as landmarks , a robot can navigate reliably, recovering its pose when necessary. Results using a multiple hypothesis testing procedure for feature localization and identiication show that accurate feature information can be...

This paper describes an approach to combining range data from both a set of sonar sensors as well as from a directional laser range nder to eeciently take advantage of the characteristics of both types of devices when exploring and mapping unknown worlds. We call our approach \just in time sensing" because it uses the more accurate but constrained laser range sensor only as needed, based upon a...

In the paper we address the problem of constructing frequency hop codes for use in multiuser communication systems such as multiple-access spread-spectrum communications and multiuser radar and sonar systems. Previous frequency hopping techniques are reviewed. The construction of a new family of frequency hop codes called hyperbolic frequency hop codes is given. Exactly p-1 codes of length p-1 ...

Recent interest in understanding the potential advantages of nonconventional detection configurations, such as bistatic vs monostatic, has driven efforts to initiate the model refinements needed to study these configurations for simple targets deployed proud or buried on the seafloor. A benchmark quality capability for these targets is utilized so that unambiguous results are available for phys...

Sidescan sonar detects objects buried in the seafloor through generating images of ordnance such as seamine buried in sediments. The sonar operates by illuminating a broad swath of the seabed using a line array of acoustic projectors while acoustic backscattering from the illuminated sediment volume is measured. The effect of suspended sediment on the sonar imagery depends on the volume scatter...