ABSTRACT Biological evidence suggests that fish use mostly anterior muscles for steady swimming while the caudal part of the body is passive and, acting as a carrier of energy, transfers the momentum to the surrounding water. Inspired by... more
ABSTRACT Biological evidence suggests that fish use mostly anterior muscles for steady swimming while the caudal part of the body is passive and, acting as a carrier of energy, transfers the momentum to the surrounding water. Inspired by those findings we hypothesize that certain swimming patterns can be achieved without copying the distributed actuation mechanism of fish but rather using a single actuator at the anterior part to create the travelling wave. To test the hypothesis a pitching flexible fin made of silicone rubber and silicone foam was designed by copying the stiffness distribution profile and geometry of a rainbow trout. The kinematics of the fin was compared to that of a steadily swimming trout. Fin’s propulsive wave length and tail-beat amplitude were determined while it was actuated by a single servo motor. Results showed that the propulsive wave length and tail-beat amplitude of a steadily swimming 50 cm rainbow trout was achieved with our biomimetic fin while stimulated using certain actuation parameters (frequency 2.31 Hz and amplitude 6.6 degrees). The study concluded that fish-like swimming can be achieved by mimicking the stiffness and geometry of a rainbow trout and disregarding the details of the actuation mechanism.
The Core-Snake aims to bridge the gap between rigid laparoscopes and flexible endoscopes. The Core-Snake
is a 10 mm diameter robot which can alter its body stiffness
from being flexible to rigid via granular jamming.
Internal impedance is one of the key factors determining the quality of embodied perception and action in biological organisms and robots. Though the role of impedance control in robotic actuation has been well studied, its significance... more
Internal impedance is one of the key factors determining the quality of embodied perception and action in biological organisms and robots. Though the role of impedance control in robotic actuation has been well studied, its significance in the accuracy of proprioception with embodied sensors is not well known yet. Therefore, it is important to characterize the relationship between the entropy of sensor information and the impedance of their physical embodiment, through which sensors feel the internal state of the body and the environment. In this paper, we address the role of internal impedance in the accuracy of embodied perception. To investigate this, we pose the problem of using only torque data measured at the stationary base of a two link planar manipulator, to estimate the deflection caused by an external torque in the McKibben type pivot joint with variable stiffness. Based on analytical modelling and experimental validation, this paper presents, for the first time, that non-linear static memory primitives relating internal impedance, internal kinematic variables, and forces felt at the base of the manipulator - similar to the functionality of tendon organs of biological counterparts - can be used to tune optimal internal impedance parameters to maximize the accuracy of internal state estimation during external perturbations.
This paper presents the use of Back propagation neural network to implement speaker verification simulated with Nigeria Languages. The focus is to verify voice patterns for different people speaking different Nigeria languagesso as to... more
This paper presents the use of Back propagation neural network to implement speaker verification simulated with Nigeria Languages. The focus is to verify voice patterns for different people speaking different Nigeria languagesso as to recognize (verify) their speech electronically.The voice samples of the people utilized were captured and then processed using the sound forge 9.0 software.The frequencies of each voice signals were used to train a backpropagation neural network, which inturn verifies the speakerthrough the voice patterns. Six neural networks (K 1
This paper describes a sensing-actuation coupling of a robotic trout that detects changes of the laminar flow speed using an on-board pressure sensor and adjusts its tail-beat frequency for steady swimming. The caudal fin actuator closely... more
This paper describes a sensing-actuation coupling of a robotic trout that detects changes of the laminar flow speed using an on-board pressure sensor and adjusts its tail-beat frequency for steady swimming. The caudal fin actuator closely mimics the morphology of a real trout, in particular the geometry, stiffness and stiffness distribution of the body and the caudal fin. We hypothesize that the linear relationship between the tail-beat frequency and speed, well-known and proven to hold for all fish studied so far, also holds for an artificial fish. We validate the hypothesis and use the results to derive a linear control law to adjust the tail- beat frequency to the swimming speed. We use an onboard pressure sensor to detect the flow speed and test the actuation in a controlled hydrodynamic environment in a flow pipe.
For industrial applications such as boilers in nuclear power plants, textile dying machines, etc., water level control is highly important. In this work, a fuzzy logic-based simple water level indicator and controller was designed and... more
For industrial applications such as boilers in nuclear power plants, textile dying machines, etc., water level control is highly important. In this work, a fuzzy logic-based simple water level indicator and controller was designed and implemented. For simplicity, the fabricated electronic level indicator defines only two (2) levels; minimum and maximum through the use of Light Emitting Diodes (LEDs). The fuzzy logic controller (FLC) was based on Mamdani type Fuzzy Inference System which has two inputs; error in level and rate of change of error with one output; valve position. The fuzzy controller was implemented in MATLAB and then simulated in Simulink to test the behavior of the system when the inputs change. The response of the fuzzy controller was then compared with a conventional PID controller for system performance check and reliability. The results obtained show that Fuzzy logic has little overshoot and steady-state error and stabilizes quickly providing accurate level control, hence can be used for rapid control with coarse adjustment. This designed controller can be tested with periodically varying liquid level tracking applications. And For better and higher accuracy, and optimized FLC by tuning the fuzzy parameters may be employed in future designs.
"The Core-Snake aims to bridge the gap between rigid laparoscopes and flexible endoscopes. The Core-Snake is a 10 mm diameter robot which can alter its body stiffness from being flexible to rigid via granular... more
"The Core-Snake aims to bridge the gap between rigid laparoscopes and flexible endoscopes. The Core-Snake is a 10 mm diameter robot which can alter its body stiffness from being flexible to rigid via granular jamming."
Abstract This paper describes a sensing-actuation coupling of a robotic trout that detects changes of the laminar flow speed using an on-board pressure sensor and adjusts its tail-beat frequency for steady swimming. The caudal fin... more
Abstract This paper describes a sensing-actuation coupling of a robotic trout that detects changes of the laminar flow speed using an on-board pressure sensor and adjusts its tail-beat frequency for steady swimming. The caudal fin actuator closely mimics the ...
