Reducing a Class of Polygonal Path Tracking to Straight Line Tracking via Nonlinear Strip-Wise Affine Transformation

In this paper a piecewise linear homeomorphism is presented that maps a strictly monotone polygonal chain to a straight line. This mapping enables one to reduce the path tracking task for mobile robots to straight line tracking. Due to the simplicity of the transformation, closed form solutions for the direct and inverse mapping are presented. Furthermore, the transformation also defines a feedback equivalence relation between the original and the transformed system equations of the mobile robot. It is shown that the form of the system equations is preserved and that the transformation essentially maps a car-like robot in the original domain, to a car-like robot in the transformed domain. This enables one to use straight line trackers developed solely for this system, for the tracking of arbitrary strictly monotone polygonal curves. Finally, it is shown that the use of this mapping can also simplify the application of existing path tracking controllers since they only need to track straight line paths. In general, one can eliminate from the existing path controllers all parameters that are needed for non-straight paths, thus obtaining respective simplified controllers. For example, it is shown that a fuzzy path controller with 135 rules can be reduced to an equivalent fuzzy straight line tracking controller with 45 rules

Autonomous SoC for fuzzy robot path tracking

In this paper a System-on-a-Chip (SoC) for the path following task of autonomous non-holonomic mobile robots is presented. The SoC consists of a digital fuzzy logic processor and a flow control program that runs under the Xilinx Microblaze™ soft processor core. The fuzzy processor implements a fuzzy path tracking algorithm introduced by the authors. The system was tied to an actual P3-DX8 robot and field experiments have been performed in order to assess the overall performance. Quantization problems and limitations imposed by the system configuration are also discussed

Tracking control using the strip-wise affine transformation: an experimental SoC design

This paper presents the analysis and application of the strip-wise affine map to the path following task for autonomous non-holonomic mobile robots. The mapping was implemented on a Spartan 3-1500 FPGA board with the use of VHDL and advanced EDA tools and was used in field experiments on a Khepera H differential robot. A fully parameterized DFLC previously published by the author has been tailored accordingly for the needs of this design implementation. Experiments were performed using a calibrated camera and a video tracking algorithm in order to extract the actual robot's path, compare it to the odometry solution and analyze the tracker's performanc

Evolution of autonomous and semi-autonomous robotic surgical systems: a review of the literature

Background: Autonomous control of surgical robotic platforms may offer enhancements such as higher precision, intelligent manoeuvres, tissue-damage avoidance, etc. Autonomous robotic systems in surgery are largely at the experimental level. However, they have also reached clinical application. Methods: A literature review pertaining to commercial medical systems which incorporate autonomous and semi-autonomous features, as well as experimental work involving automation of various surgical procedures, is presented. Results are drawn from major databases, excluding papers not experimentally implemented on real robots. Results: Our search yielded several experimental and clinical applications, describing progress in autonomous surgical manoeuvres, ultrasound guidance, optical coherence tomography guidance, cochlear implantation, motion compensation, orthopaedic, neurological and radiosurgery robots. Conclusion: Autonomous and semi-autonomous systems are beginning to emerge in various interventions, automating important steps of the operation. These systems are expected to become standard modality and revolutionize the face of surgery

Incremental 2D delaunay triangulation core implementation on FPGA for surface reconstruction via high-level synthesis

This paper presents a 2D Delaunay triangulation core for surface reconstruction implemented on a Field Programmable Gate Array (FPGA) chip. The core implementation is derived using high-level synthesis from a C++ description of an incremental 2D Delaunay triangulation algorithm. This description was modified accordingly so that it can be embedded into a FPGA chip using hardware description language. Goal of this work is to increase the execution speed of the algorithm so as to allow for real-time operation. Towards this end, we performed an optimization process using high level synthesis directives which pipeline regions of the code in order to achieve delay optimization. We show preliminary results using standard benchmark models for surface reconstruction, which show the performance of our design