Efficient Data Acquisition in MATLAB: Streaming HD Video in real-time

The acquisition and processing of a video stream can be very computationally expensive. Typical image processing applications split the work across multiple threads, one acquiring the images, and another one running the actual algorithms. In MATLAB© we can get multi-threading by interfacing with other languages, but there is a significant cost associated with exchanging data across the resulting language barrier. In this blog post, we compare different approaches for getting data through MATLAB’s Java interface, and we show how to acquire high-resolution video streams in real-time and with low overhead.

Read More

Using MATLAB for hardware-in-the-loop prototyping #1 : Message Passing Systems

MATLAB© is a programming language and environment designed for scientific computing. It is one of the best languages for developing robot control algorithms and is widely used in the research community. While it is often thought of as an offline programming language, there are several ways to interface with it to control robotic hardware 'in the loop'. As part of our own development we surveyed a number of different projects that accomplish this by using a message passing system and we compared the approaches they took. This post focuses on bindings for the following message passing frameworks: LCM, ROS, DDS, and ZeroMQ.

Read More

Analyzing the viability of Ethernet and UDP for robot control

Ethernet is the most pervasive communication standard in the world. However, it is often dismissed for robotics applications because of its presumed non-deterministic behavior. In this article, we show that in practice Ethernet can be made to be extremely deterministic and provide a flexible and reliable solution for robot communication.

Read More

 

A Practical Look at Latency in Robotics : The Importance of Metrics and Operating Systems

Latency is an important practical concern in the robotics world that is often poorly understood. We feel that a better understanding of latency can help robotics researchers and engineers make design and architecture decisions that greatly streamline and accelerate the R&D process. We’ve spent many hours looking for information on the latency characteristics of various robotic components, but have had difficulty finding anything that is clearly presented or backed by solid data. From what we’ve found, most benchmarks focus on the maximum throughput and either ignore the subject of latency or measure it incorrectly.

Read More