5,323 research outputs found
Simple Obstacle Avoidance Algorithm for Rehabilitation Robots
The efficiency of a rehabilitation robot is improved by offering record-and-replay to operate the robot. While automatically moving to a stored target (replay) collisions of the robot with obstacles in its work space must be avoided. A simple, though effective, generic and deterministic algorithm for obstacle avoidance was developed. The algorithm derives a collision free path of the end-effector of the robot around known obstacles to the target location in O(n) time. In a case study, using the rehabilitation robot ARM, the performance of the algorithm was tested. As was a newly human-machine-interface offering this record-and-replay functionality to the use
A survey on fractional order control techniques for unmanned aerial and ground vehicles
In recent years, numerous applications of science and engineering for modeling and control of unmanned aerial vehicles (UAVs) and unmanned ground vehicles (UGVs) systems based on fractional calculus have been realized. The extra fractional order derivative terms allow to optimizing the performance of the systems. The review presented in this paper focuses on the control problems of the UAVs and UGVs that have been addressed by the fractional order techniques over the last decade
Reinforcement Learning With Temporal Logic Rewards
Reinforcement learning (RL) depends critically on the choice of reward
functions used to capture the de- sired behavior and constraints of a robot.
Usually, these are handcrafted by a expert designer and represent heuristics
for relatively simple tasks. Real world applications typically involve more
complex tasks with rich temporal and logical structure. In this paper we take
advantage of the expressive power of temporal logic (TL) to specify complex
rules the robot should follow, and incorporate domain knowledge into learning.
We propose Truncated Linear Temporal Logic (TLTL) as specifications language,
that is arguably well suited for the robotics applications, together with
quantitative semantics, i.e., robustness degree. We propose a RL approach to
learn tasks expressed as TLTL formulae that uses their associated robustness
degree as reward functions, instead of the manually crafted heuristics trying
to capture the same specifications. We show in simulated trials that learning
is faster and policies obtained using the proposed approach outperform the ones
learned using heuristic rewards in terms of the robustness degree, i.e., how
well the tasks are satisfied. Furthermore, we demonstrate the proposed RL
approach in a toast-placing task learned by a Baxter robot
Brain-Computer Interface meets ROS: A robotic approach to mentally drive telepresence robots
This paper shows and evaluates a novel approach to integrate a non-invasive
Brain-Computer Interface (BCI) with the Robot Operating System (ROS) to
mentally drive a telepresence robot. Controlling a mobile device by using human
brain signals might improve the quality of life of people suffering from severe
physical disabilities or elderly people who cannot move anymore. Thus, the BCI
user is able to actively interact with relatives and friends located in
different rooms thanks to a video streaming connection to the robot. To
facilitate the control of the robot via BCI, we explore new ROS-based
algorithms for navigation and obstacle avoidance, making the system safer and
more reliable. In this regard, the robot can exploit two maps of the
environment, one for localization and one for navigation, and both can be used
also by the BCI user to watch the position of the robot while it is moving. As
demonstrated by the experimental results, the user's cognitive workload is
reduced, decreasing the number of commands necessary to complete the task and
helping him/her to keep attention for longer periods of time.Comment: Accepted in the Proceedings of the 2018 IEEE International Conference
on Robotics and Automatio
- …