The aye-aye (Daubentonia madagascariensis) is a nocturnal lemur native to the island of Madagascar with a unique thin middle finger. Its slender third digit has a remarkably specific adaptation, allowing them to perform tap-scanning to locate small cavities beneath tree bark and extract wood-boring larvae from it. As an exceptional active acoustic actuator, this finger makes an aye-aye’s biological system an attractive model for pioneering Nondestructive Evaluation (NDE) methods and robotic systems. Despite the important aspects of the topic in the aye-aye’s unique foraging and its potential contribution to the engineering sensory, little is known about the mechanism and dynamics of this unique finger. This paper used a motion-tracking approach for the aye-aye’s middle finger using simultaneous video graphic capture. To mimic the motion, a two-link robot arm model is designed to reproduce the trajectory. Kinematics formulations were proposed to derive the motion of the middle finger using the Lagrangian method. In addition, a hardware model was developed to simulate the aye-aye’s finger motion. To validate the model, different motion states such as trajectory paths and joint angles, were compared. The simulation results indicate the kinematics of the model were consistent with the actual finger movement. This model is used to understand the aye-aye’s unique tap-scanning process for pioneering new tap-testing NDE strategies for various inspection applications.
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Pioneering a biomimetic approach for the acoustic near-field measurement of aye-aye biological auditory system
The aye-aye (Daubentonia madagascariensis) is the largest nocturnal primate in the world and possesses a number of distinct adaptations. The most striking feature of the aye-aye is perhaps its exceptional near-field auditory system adopted to support its unique tap-scanning process. This tap-scanning technique represents prominent evolutionary innovations in the animal’s biological auditory system. The current study provides an initial insight into proposing a biomimetic approach to determine how different morphological features might impact the ayeaye’s acoustic near-field auditory system. The experimental setup comprised a miniature piezoelectric hammer mounted on a Universal Robotics manipulator (UR5) (the integrated system provides a controlled tapping process) and a prepolarized capacitive measurement microphone (to capture the acoustic sound coming from each tap on the wooden sample). The pinnae of the aye-aye were 3D printed using a CT scan obtained from a carcass. The results show that the biomimetic setup can successfully be used for evaluating the near-field auditory system of aye-ayes.
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- Award ID(s):
- 2047033
- PAR ID:
- 10343955
- Editor(s):
- Lakhtakia, Akhlesh; Martín-Palma, Raúl J.; Knez, Mato
- Date Published:
- Journal Name:
- SPIE, Smart Structures/NDE, 300 Long Beach Blvd, Long Beach, CA, 2022
- Page Range / eLocation ID:
- 13
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Lakhtakia, Akhlesh; Martín-Palma, Raúl J.; Knez, Mato (Ed.)The aye-aye (Daubentonia madagascariensis) is a nocturnal lemur native to the island of Madagascar with a special thin middle finger. The aye-aye’s third digit (the slenderest one) has a remarkably specific adaptation, allowing it to perform tap-scanning (Finger tapping) to locate small cavities beneath tree bark and extract woodboring larvae from it. This finger, as an exceptional active acoustic actuator, makes an aye-aye’s biological system an attractive model for Nondestructive Evaluation (NDE) methods and robotic systems. Despite the important aspects of the topic in engineering sensory and NDE, little is known about the mechanism and movement of this unique finger. In this paper a simplified kinematic model was proposed to simulate the aye-aye’s middle finger motion.more » « less
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