Ayoung Hong

A visual and force feedback for multi-robot teleoperation in outdoor environments: A preliminary result

For teleoperation of multiple mobile robots (e.g., unmanned aerial vehicles), a better situational awareness of remote environments is crucial for good performance. Visual and force feedback are the most common ways to perceive the environments accurately using a vision system and a haptic device, respectively. In outdoor environments, however, it is difficult to use adequate/accurate sensors (e.g., global localization system) for haptic feedback of the remote environments as well as the slave robots. In this paper, we propose a visual and force feedback method to enhance a human operators situational awareness in multi-robot teleoperation by fabricating a global view of the multi-robot system and transmitting velocity information of one, respectively, using only local information of the robots. The proposed visual feedback method, then, is evaluated via two psychophysical experiments: maneuvering and searching tests. Several measures are also proposed to assess the human operators maneuverability and situational awareness quantitatively.

Multimodal feedback for teleoperation of multiple mobile robots in an outdoor environment

Better situational awareness helps understand remote environments and achieve better performance in the teleoperation of multiple mobile robots (e.g., a group of unmanned aerial vehicles). Visual and force feedbacks are the most common ways of perceiving the environments accurately and effectively; however, accurate and adequate sensors for global localization are impractical in outdoor environments. Lack of this information hinders situational awareness and operating performance. In this paper, a visual and force feedback method is proposed for enhancing the situational awareness of human operators in outdoor multi-robot teleoperation. Using only the robots’ local information, the global view is fabricated from individual local views, and force feedback is determined by the velocity of individual units. The proposed feedback method is evaluated via two psychophysical experiments: maneuvering and searching tests using a human/hardware-in-the-loop system with simulated environments. In the tests, several quantitative measures are also proposed to assess the human operator’s maneuverability and situational awareness. Results of the two experiments show that the proposed multimodal feedback enhances only situational awareness of the operator.

Tracking a magnetically guided catheter with a single rotating C-Arm

This paper presents a method to localize a magnetically guided catheter using a single rotating C-Arm. Because the three dimensional position of the catheter tip, when extracted from a single view, contains large uncertainties, we propose to combine multiple views by rotating the C-Arm and using a Kalman filter. The proposed approach yields good tracking performance for several catheter poses and reduces the maximum estimated standard deviation to 0.3 cm after incorporating six views. This represents a 62 percent reduction in three dimensional position uncertainty.

Magnetic needle guidance for neurosurgery: Initial design and proof of concept

A magnetic-tip steerable needle is presented with application to aiding deep brain stimulation electrode placement. The magnetic needle is 1.3mm in diameter at the tip with a 0.7mm diameter shaft, which is selected to match the size of a deep brain stimulation electrode. The tip orientation is controlled by applying torques to the embedded neodymium-iron-boron permanent magnets with a clinically-sized magnetic-manipulation system. The prototype design is capable of following trajectories under human-in-the-loop control with minimum bend radii of 100mm without inducing tissue damage and down to 30mm if some tissue damage is tolerable. The device can be retracted and redirected to reach multiple targets with a single insertion point.