Performance test of EtherCAT servo driver for real-time synchronous control

The control system of a highly dynamic robot requires the ability to respond quickly to changes in the robot’s state. This type of system is needed in varying fields such as dynamic locomotion, multicopter control, and human-robot interaction. Robots in these fields require software and hardware capable of hard real-time, high frequency control. In addition, the application outlined in this paper requires modular components, remote guidance, and mobile control. The described system integrates a computer on the robot for running a control algorithm, a bus for communicating with microcontrollers connected to sensors and actuators, and a remote user interface for interacting with the robot. Current commercial solutions can be expensive, and open source solutions are often time consuming. The key innovation described in this paper is the building of a control system from existing — mostly open source — components that can provide realtime, high frequency control of the robot. This paper covers the development of such a control system based on ROS, OROCOS, and EtherCAT, its implementation on a dynamic bipedal robot, and system performance test results.

Download Full-text

TTEthernet Transmission in Software-Defined Distributed Robot Intelligent Control System

Wireless Communications and Mobile Computing ◽

10.1155/2018/8589343 ◽

2018 ◽

Vol 2018 ◽

pp. 1-13 ◽

Cited By ~ 1

Author(s):

Caibing Liu ◽

Fang Li ◽

Guohao Chen ◽

Xin Huang

Keyword(s):

Internet Of Things ◽

Real Time ◽

Performance Test ◽

New Technologies ◽

Simulation Software ◽

Utilization Rate ◽

Intelligent Control System ◽

Time Performance ◽

Industrial Iot ◽

Smart Technologies

With the integration of new technologies such as smart technologies and cloud computing in the industrial Internet of Things, the complexity of industrial IoT applications is increasing. Real-time performance and determinism are becoming serious challenges for system implementation in these Internet of Things systems, especially in critical security areas. This paper provides a framework for a software-defined bus-based intelligent robot system and designs scheduling algorithms to make TTEthernet play the role of scheduling in the framework. Through the framework, the non-real-time and uncertainties problem of distributed robotic systems can be solved. Moreover, a fragment strategy was proposed to solve the problem of large delay caused by Rate-Constrained traffic. Experimental results indicate that the improved scheme based on fragmentation strategy proposed in this paper can improve the real-time performance of RC traffic to a certain extent. Besides, this paper made a performance test and comparison experiments of the improved scheme in the simulation software to verify the feasibility of the improved scheme. The result showed that the delay of Rate-Constrained traffic was reduced and the utilization rate of network was improved.

Download Full-text

Application of MECHATROLINK-II Fieldbus in Multi-Axis Embedded CNC System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.314-316.1695 ◽

2011 ◽

Vol 314-316 ◽

pp. 1695-1701

Author(s):

Wei Qiang Gao ◽

Chao Ting Qing ◽

Ze Hua Hu ◽

Zou Ya Huang

Keyword(s):

Embedded Systems ◽

Embedded System ◽

Real Time ◽

Numerical Control ◽

Control Problems ◽

Cnc System ◽

Control Field ◽

Synchronous Control ◽

Embedded Cnc ◽

Transmission Bottleneck

Recently, the application of ﬁeldbus is becoming a trend in the development of CNC system towards decentralisation, network and multi-axis linkage. It is anticipated that ﬁeldbus will be one of the leading technologies in the area of numerical control before long. Meanwhile, embedded system has been widely used in numerical control field to solve the reliability and real-time problems. In order to give full play to the advantages of embedded systems, the MECHATROLINK-II fieldbus is introduced to solve the transmission bottleneck of servo communications and multi-axis synchronous control problems. And it is proved that the application scheme combined fieldbus and embedded system is successful and valid by a large amount of performance testings.

Download Full-text

Time Optimization for Lossy Decompression of the LISA Sensor Data on LAPAN A3 Satellite Using a Grouping Method of HUFFMAN Code Bit Number

Jurnal Teknologi Dirgantara ◽

10.30536/j.jtd.2018.v16.a2960 ◽

2018 ◽

Vol 16 (1) ◽

pp. 23

Author(s):

Suhermanto M.T

Keyword(s):

Real Time ◽

Performance Test ◽

Data Extraction ◽

Extraction Process ◽

Lossy Compression ◽

Extraction Time ◽

Sensor Data ◽

Multispectral Data ◽

Grouping Method ◽

The Fourier Transform

The LAPAN-A3 satellite provides compressed multispectral data from LISA sensor using real-time lossy compression. The compression of the multispectral data of radiometric resolution 12bit/pixel is built from the Fourier transform and the use of Huffman decoder 514 binary length code. A problem arised in the data extraction process, that decompression performance is very slow because the search method of code value in Hufman table was done sequentially from one bit to the next bit in one block of data along 4000 pixels. The data extraction time for one scene in 12 minutes acquisition duration (one full path) takes up to 20 hours. This paper proposes a method of improving the LISA real-time lossy data decompression algorithm using the grouping method of bit code on the Huffman decoding algorithm and using pointer for reading data in the buffer memory. Using this method, the searching process of bit code for all characters in the Huffman decoder algorithm is done regularly, so the search processing time is significantly reduced. The performance test used 6 data samples. The result showed that extraction time has an average of 14 times faster. The lossy compression ratio is still in accordance with the design specification of LISA sensor that is less than 4 times and the appearance of the special character is very small i.e. less than 0.5%.

Download Full-text

Real-time performance test of an vision-based inertial SLAM

ICCAS 2010 ◽

10.1109/iccas.2010.5670282 ◽

2010 ◽

Author(s):

Sukchang Yun ◽

Byoung-Jin Lee ◽

Young Jae Lee ◽

Sangkyung Sung

Keyword(s):

Real Time ◽

Performance Test ◽

Time Performance

Download Full-text

Development of Railway Protective Relay Simulator for Real-Time Applications

Applied Sciences ◽

10.3390/app10010191 ◽

2019 ◽

Vol 10 (1) ◽

pp. 191 ◽

Cited By ~ 2

Author(s):

Joorak Kim ◽

Gyu-Jung Cho ◽

Jaewon Kim

Keyword(s):

Real Time ◽

Performance Test ◽

Dynamic Testing ◽

Circuit Breaker ◽

Phase System ◽

Protective Relay ◽

Waveform Generation ◽

Traction Power Supply System ◽

Protective Relays ◽

Traction Power Supply

Electric railways use a single-phase system, with the line comprising a trolley wire (TF) that supplies power to the load with a neutral wire and an autotransformer (AF) feeder to absorb the return current of the rail. Testing the performance of the protective relay that detects the fault of the traction power-supply system (TPSS) and operates the circuit breaker is very important. Until now, the performance test of protective relays for the TPSS has been conducted via a simple-steady test or using an expensive real-time simulator. However, under a fast-moving environment in which the load consumes a large amount of power, the protective relay must always detect faults and operate properly. This paper proposes a digital simulator that enables the dynamic testing of protective relays without using any steady test and expensive real-time simulators. This simulator includes both external waveform import and internal waveform generation functions. Users can test the operation of the protective relay by entering the waveform generated externally or internally into the protective relay. Additionally, it has the ability to monitor the operating protection elements and pickup time when the protective relay detects a fault and orders the circuit breaker trip.

Download Full-text