In part 1 of our brief overview of outdoor environment detection processes, we discussed time-of-flight as well as radar technology. In part 2, we presented ultrasound and mono/stereo video processes. In this third and last part of our article series, we want to take a closer look at laser technology.
In part 1 of our brief overview of outdoor environment detection processes, we discussed time-of-flight as well as radar technology. In the following, we now want to take a closer look at ultrasound as well as environment detection with the help of video images. In the final part of our article series, we will discuss laser technology.
After the first participation in the B2RUN-corporate challenge Kaiserslautern last year, the Robot Makers Running Team again took part in the running event in Kaiserslautern’s inner city this year. Thus, the six-kilometer route, which stretches from the SAKS hotel through the pedestrian zone over Barbarossa and Bismarckstrasse back to the Stiftsplatz, was tackled by eight brave runners.
After our first participation in the B2RUN-Corporate Challenge last year, we will again face the challenge of the sporting spectacle on the 18th of May 2017 in our hometown. With nine runners our team is going to overcome the approximately five kilometer-long run through the Kaiserslautern city center. Our team starts in the last starting block at 6:30 pm at the Stiftsplatz in front of the SAKS-Hotel. Friends, patrons and partners are, of course, invited to support our team at the track!
The autonomous vineyard crawler of the Robot Makers GmbH will be discussed in the current issue of the newsletter of the Commercial Vehicle Cluster Southwest, the so called cvc-news 01/2017. The task that has been implemented in this project, fits perfectly with the newly selected focus of the innovative commercial vehicle cluster – “Automated Commercial Vehicles for the Off-Road-Sector”.
For the implementation of modern assistance functions as well as the (partial) autonomy of utility vehicles, the vehicle – depending on intended application – must be in a position to localize itself in its environment, recognize obstacles in the planned driving route, and respond adequately to these. This can be achieved, for example, by stopping in front of the obstacle or circumventing it. In order to detect structures such as obstacles in the immediate environment, mobile machines must therefore have some degree of ability to “perceive” the immediate environment.
By now, there are various sensor systems, each based on different measuring principles, that compete with one another in so-called environment detection. There is no general answer as to which method is the best option, or whether a combination of different sensor systems (sensor fusion) makes sense. Depending on the type of application, what exactly the sensor should recognize has to be determined. Other important considerations include in what resolution the information should be available, in what type of environment the application takes place, or how expensive the sensor should be. These are just a few of the questions you have to ask yourself when selecting the best environment sensor technology for your application. So that you can get an overview of the most common processes in environment detection, we want to present them here briefly. In the first part of this article, we will look at the process of time-of-flight as well as radar technology.
Environment detection using infrared light: the time-of-flight camera
One means of environment detection consists of measuring distance using a time-of-flight camera (TOF camera). This type of camera uses a so-called photonic mixing device (PMD sensor) as an image sensor. This sensor operates on the time-of-flight principle for which the camera is named.
With this process, an infrared light signal is emitted that, in turn, is received by a sensor. Based on the runtime of the light and the known, constant speed of light, the distance of the object to the PMD sensor can be determined. The closer the object is to the PMD sensor, the shorter the measured light runtime. The further the object is away, the longer the runtime of the infrared rays.
Through the technology of the TOF camera, it is possible to measure this light runtime in pixels and thereby create a three-dimensional representation of the current scene. This data capture is so fast that even real-time requirements can be achieved with it.
TOF cameras are already being tested and applied in driver assistance systems or safety sensors in the automotive industry (pedestrian recognition, emergency brake assistance, etc.). The mobile robotics sector also uses this technology frequently, for example, to recognize obstacles or to follow individuals.
Old technology in new applications: radar
Radar stands for “Radio Detection and Ranging” and describes various localization and recognition processes that use electromagnetic waves. Here, we are thus dealing with a non-visual process for measuring distance. The origins of radar date to 1886 when Heinrich Hertz discovered that metal objects reflect radio waves. Christian Hülsmeyer subsequently worked on the subject of localization using these waves. In 1904, he applied for a patent for the first precursor to today’s radar systems, the telemobiloscope.
A radar device sends out bundled electromagnetic waves that an object within sight distance then reflects. These reflected radio waves are received back by the radar device and subsequently evaluated. In this manner, conclusions about the distance to an object, its direction and relative motion and, when considering consecutive measurements, even the speed of an object can be drawn.
With radar devices used for environment detection, the frequency modulated continuous wave (FMCW) radar is generally employed. In contrast to impulse radar devices, this type of radar sends out a continuous signal, but constantly changes the transmission frequency. Most people are familiar with this process through “speed traps” set up by the police used extensively in law enforcement. In addition to measuring speed, such a radar also measures the distance of the speeding vehicle to the camera and triggers it just at the right moment.
Other applications for radar sensors include motion and (filling) level sensors, or use in adaptive cruise control systems for cars. In these, they detect the speed of and distance to the car driving ahead. Based on this information, the speed of your car can be modified, or emergency braking initiated.
From 25th to 27th January 2017, our partner Niko Maschinenbau will present the driverless vineyard crawler to the visitors at the machine exhibition of the Agrartage Nieder-Olm. For the first time, the machine itself will be represented on the booth of our partner in Hall C, Stand 024. Robot Motors GmbH and Niko Maschinenbau would be really happy to welcome you there.
Thanks to the technology of the Robot Makers GmbH, this crawler vehicle is able to complete various care tasks in the vineyard completely autonomously. In contrast to other systems on the market, the machine doesn’t use the high-precision RTK-GPS. Most of the data used for navigation is provided by the “eyes” of the vehicle, so-called ambient environment sensors. In addition to independently running the rows in wine and fruit cultivation, the vehicle is also able to turn independently at the row exit and enter the next row. This allows complete plantations to be processed autonomously.
By eliminating the necessity of the highly accurate RTK-GPS signal, the system achieves greater robustness against signal fluctuations caused by shading (e.g. because of trees or precipices) and weather phenomena. In addition, the position offset arising by the slippage of the crawler while the transposition maneuver can be counterbalanced. This offset forces today’s systems, which are based on precisely predefined tracks, to come to a standstill.
The team of Robot Makers GmbH wishes all customers, partners and friends a happy and peaceful Christmas and a happy new year. We are pleased to be able to implement exciting projects with you in 2017 and to help you with all questions concerning mobile automation.
For the fifth year in a row, employees and friends of the Robot Makers GmbH gathered at the christmas market in Kaiserslautern to say goodbye to the last year and to agree on the new year 2017 with many exciting projects. In addition to our employees, this year again some former colleagues as well as friends and acquaintances of our company followed our call and together we spent a beautiful pre-christmas evening.
The Robot Makers GmbH wants to take this opportunity to thank all of its customers, partners and friends for the cooperation in last year and to wish Merry Christmas and a good start to the new year 2017 to everyone.
From 27 to 30 November, the Intervitis, Interfructa, Hortitechnica, a major trade fair for wine, juice and special cultures took place on the grounds of the Landesmesse Stuttgart. In addition to the latest developments in cultivation and harvesting technology, innovations in the areas of handling, process control, marketing and architecture were also presented. Therefore, a good overview above the entire process chain from cultivation to marketing was provided. Members of Robot Makers GmbH were also on the road during the four exhibition days, both as exhibitors and visitors.