Cellular Vehicle-to-Everything (C-V2X) technology is transforming the transportation industry by enabling advanced communication between vehicles, infrastructure, and other road users. This breakthrough technology has the potential to improve road safety, reduce traffic congestion, and support the development of autonomous vehicles.

Designing C-V2X Communication Systems: Key Engineering Considerations and Best Practices

<section id="isPasted">Team Polar, a student team at Eindhoven University of Technology (TU/e), took their first rover to perform research in the Norwegian snow in the first week of January. The team is dedicated to developing an independent rover that can perform Antarctic research. This is their first working prototype and the team is eager to set a benchmark for future developments. They will present their findings and the rover itself on the reveal event, January 20, 2023.</section><section tabindex="-1">The Earth is facing its biggest problem in centuries: climate change. To fight climate change, we need to understand better the factors behind climate change. However, understanding it requires gathering information about our planet in places where nature is still pristine and more or less unaffected by climate change, as well as places where the consequences of global warming and climate change can be observed first-hand. Circumstances like that are usually found in extremely cold, and remote environments like the Arctics, Antarctica, and the oldest glaciers. At the moment, research is often carried out inefficiently and in very expensive and unsustainable ways.<a href="https://teampolar.org/" target="_blank">Team Polar</a> wants to create an alternative way to do all kinds of environmental, extensive research in the coldest places of our planet by developing an unmanned rover. This rover will eventually operate and perform research all by itself - similar to how the Martian rovers operate on the surface of Mars - and collect invaluable data about the effects of climate change. The team started its mission in 2018 and now presents its first working prototype: the rover &lsquo;Ice Cube&rsquo;.<h2>Research in the snow</h2>Development of the rover took place at the Eindhoven University of Technology in the Netherlands, a country notoriously devoid of deep snow most winters these days. That&rsquo;s why the team took their rover to Trondheim in Norway, to see how their first rover &lsquo;Ice Cube&rsquo; performs in the snow. &ldquo;We can test a lot of things in our lab, but not how the rover drives in the snow, how the solar panels handle the snow and temperatures, and how cold it will get inside the rover and how quickly it becomes very cold,&rdquo; explains team manager Laurenz Edelmann.&ldquo;We have built our first rover with off-the-shelf components. That may or may not present some challenges for us. And, we may find that certain components will need to be custom-made and designed for future rover models. That&rsquo;s why this rover will be a benchmark for us and for future teams.&rdquo; The rover will be remote controlled for now, allowing the team to hand-pick the locations they want to study on this trip. This allowed the team to gather essential insights that can help the team to ensure that their next rover will be fit for a mission to Antarctica.<img src="https://s3-us-west-1.amazonaws.com/wevolver-project-images/froala%2F1674079732566-csm_740c39b4-f736-414a-9c37-377bf1b2a7b9_368fa77a48.jpg" style="width: 300px;" class="fr-fic fr-dib">Rover Ice Cube. Photo: Laurenz Edelmann, team POLAR&nbsp;<h2 id="isPasted">Inspiring other teams</h2>The team was in Norway to run their experiments from January 4th until January &nbsp;8th. There, they saw their rover drive through the snow like a natural. They also gained a insights in which components worked fine, and the handful of items that broke and needed replacing. &ldquo;Overall, we were super impressed with the way Ice Cube tackled the snow and handled itself,&rdquo; says Edelmann. &ldquo;We gathered valuable data, and great footage to present at our event.&rdquo; There was also time set aside on the return journey to the Netherlands to visit other universities. &ldquo;We love to maintain good relations with other student teams at technical universities in Europe. That&rsquo;s why we made sure to present our rover at the universities of Trondheim (NTNU), Kopenhagen (DTU), and Braunschweig (NFF),&rdquo; explains Edelmann.&ldquo;We hope to inspire and inform local student teams how to tackle an ambitious goal, such as building an Antarctic research rover, successfully. And, of course, to forge new alliances and collaborations with our colleagues at other institutions.In Eindhoven, student teams get access to a lot of facilities. We were happy to build our rover in the Innovation Space workshop, with its excellent facilities and experts to coach us. Our partners also helped make this possible with funds and materials. This trip wouldn&rsquo;t have been possible without sponsoring from the University Fund Eindhoven (UFe) and EuroTech Universities.&rdquo;<h2>Meet the team and their rover</h2>On Friday January 20th, the team presents their rover &lsquo;Ice Cube&rsquo; to the world after 2 years of design and development. This is a unique opportunity to see the rover up close, meet the team, and ask the researchers, scientists, adventurers, and explorers questions about their work on the rover. The reveal will take place at 4 pm in the Blauwe Zaal in the Auditorium building on the TU/e campus&nbsp;<a href="https://www.tue.nl/en/our-university/calendar-and-events/20-01-2023-teampolarprototyperevealevent/" target="_blank">and tickets are already available</a>.&ldquo;We have a great event planned and are looking forward to showcasing the rover, sharing footage of our trip, and discussing opportunities for collaboration with those present at the launch event,&rdquo; says Nikolett Marton, team Polar&rsquo;s marketing manager.<hr>This article was first published here:&nbsp;<a href="https://www.tue.nl/en/news-and-events/news-overview/12-01-2023-antarctic-rover-performs-research-in-the-snow/" id="isPasted" rel="noopener noreferrer" target="_blank">https://www.tue.nl/en/news-and-events/news-overview/12-01-2023-antarctic-rover-performs-research-in-the-snow/</a></section>

Team POLAR's rover Ice Cube in the Norwegian snow. Photo: Laurenz Edelmann, team POLAR

On January 20, Team POLAR showcases its first vehicle for independent climate research in icy, inhospitable regions such as the North and South Poles.

Antarctic rover performs research in the snow

This article is a part of our <a href="http://www.wevolver.com/student-program" target="_blank">University Technology Exposure Program</a>. The program aims to recognize and reward innovation from engineering students and researchers across the globe.&nbsp;<h2 dir="ltr">Introduction</h2>The article presents a concise description of the mathematical approach for planning the autonomous vehicle (AV) motion in a constrained space.&nbsp;From the point of view of reducing the necessary procedures in motion planning, simultaneous optimization of the trajectory and kinematic parameters would be preferable. However, with such an approach, it is difficult to satisfy all criteria, which often contradict each other, and the final objective function requires detailed study. In contrast, the proposed technique offers a two-stage prediction of the AV motion, demonstrating its mathematical logicality, clarity, workability, and efficiency on a generalized example of curvilinear movement in conditions of external boundaries and a moving obstacle.<h2 dir="ltr">What is the technology about? An overview</h2>The submission represents an overview of the developed technique for planning the AV motion reference parameters. The predictions of trajectory, speed, acceleration, and other AV's kinematic parameters are determined using sequential optimization. The proposed approach combines the basic principles of the finite element method (FEM) and nonlinear optimization with nonlinear constraints.&nbsp;First, the generalization on representing an arbitrary function by finite elements (FE) is briefly described. A one-dimension FE with two nodes and three degrees of freedom (DOF) in a node was chosen as the basic one, corresponding to the 5th-degree polynomial.&nbsp;Next, a method for determining the motion trajectory is developed. The following are considered: formation of a restricted space for the AV's allowable maneuvering, the geometry of motion trajectory and its relation with vehicle steerability parameters, cost functions and their influences on the desirable trajectory's nature, compliance of nonlinear restrictions of the node parameters with the motion area boundaries. At the second stage, a technique for optimizing AV speed and acceleration redistribution is elaborated.&nbsp;The model considers possible combinations of cost functions, conditions of limiting the kinematic parameters with the tire slip critical speed, maximum speed level, maximum longitudinal acceleration, and critical lateral acceleration. In the simulation section, several variants of trajectories were searched and compared. Several versions of distributing the longitudinal speed and acceleration curves are determined, and their comparative analysis is fulfilled.<h2 dir="ltr">What sub-systems is technology composed of?</h2>The mechanism of forming the boundaries of permissible movement in the presence of a movable obstacle is stipulated. Criteria for finding optimal trajectory plans and distribution of kinematic parameters are determined and analyzed, considering geometric, kinematic, and physical restrictions, including the vehicle performance potential. A series of virtual tests have been carried out for the generalized example of searching for motion predictions, demonstrating the consistency of the proposed technique and the quality of the resulting plans.<h2 dir="ltr">What tasks do they fulfill?</h2>The first stage is based on ensuring movement safety in the zone of admissible boundaries and stability of control due to the optimal smoothness of the predicted trajectory, considering the geometric and kinematic characteristics of the AV model. The second stage ensures the distribution of kinematic parameters along the trajectory length, the main of which are the longitudinal speed and acceleration, based on minimizing the complex criteria determined by the internal vehicle potential and the physics of tire-road interaction. The geometric, kinematic, and physical nonlinear constraints used in the optimization steps contribute to the realism and feasibility of the proposed planning technique.<h2 dir="ltr">How are these sub-systems integrated?</h2>To test the approach proposed, several variants of planning trajectories and speeds were performed based on the composed MATLAB code using the basic nonlinear optimization function fmincon. The primary necessary physical, kinematic, and geometric data (Fig. 3) of the vehicle Audi A4 Quattro were used.<h2 dir="ltr">Were any issues/obstacles resolved through clever component reengineering or innovative solutions?</h2>From the point of view of reducing the necessary procedures in motion planning, simultaneous optimization of the trajectory and kinematic parameters would be preferable. However, with such an approach, it is difficult to satisfy all criteria, which often contradict each other, and the final objective function requires detailed study. In contrast, the proposed technique offers a two-stage prediction of the AV motion, demonstrating its mathematical logicality, clarity, workability, and efficiency on a generalized example of curvilinear movement in conditions of external boundaries and a moving obstacle.<h2 dir="ltr">Supporting materials (technical drawings, schematics, illustrations, animations, etc.)</h2><img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjQ1NTUwMzA0NjUwLWltYWdlNS5qcGciLCJlZGl0cyI6eyJyZXNpemUiOnsid2lkdGgiOjk1MCwiZml0IjoiY292ZXIifX19" class="fr-fic fr-dii" style="width: 756px;" alt="planning the AV's maneuver">Figure 1. Scheme of the generalized task of planning the AV's maneuver<img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjQ1NTUwMzE5NTc0LWltYWdlMS5qcGciLCJlZGl0cyI6eyJyZXNpemUiOnsid2lkdGgiOjk1MCwiZml0IjoiY292ZXIifX19" class="fr-fic fr-dii">Figure 2. Forming the boundaries of the allowable area before planning a maneuver<img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjQ1NTUwMzI3MjM4LWltYWdlNC5qcGciLCJlZGl0cyI6eyJyZXNpemUiOnsid2lkdGgiOjk1MCwiZml0IjoiY292ZXIifX19" class="fr-fic fr-dii" alt="Relations between the mass center's trajectory and the vehicle kinematics">Figure 3. Relations between the mass center's trajectory and the vehicle kinematics&nbsp;&nbsp;<img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjQ1NTUwMzM2MjEzLWltYWdlOC5qcGciLCJlZGl0cyI6eyJyZXNpemUiOnsid2lkdGgiOjk1MCwiZml0IjoiY292ZXIifX19" class="fr-fic fr-dii" alt="critical interactions with the motion boundaries">Figure 4. Scheme of the critical interactions with the motion boundaries&nbsp;<img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjQ1NTUwMzY4OTM0LWltYWdlNy5qcGciLCJlZGl0cyI6eyJyZXNpemUiOnsid2lkdGgiOjk1MCwiZml0IjoiY292ZXIifX19" class="fr-fic fr-dii" alt="Variants of vehicle motion geometry depending on the priority criteria">Figure 5. Variants of vehicle motion geometry depending on the priority criteria: a) mass center trajectories, b) yaw angles<img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjQ1NTUwMzc4NDk1LWltYWdlMy5qcGciLCJlZGl0cyI6eyJyZXNpemUiOnsid2lkdGgiOjk1MCwiZml0IjoiY292ZXIifX19" class="fr-fic fr-dii" alt="Results of the optimal plans for redistributing the kinematic parameters">Figure 6. Results of the optimal plans for redistributing the kinematic parameters:a) longitudinal speed along the trajectory,b) longitudinal acceleration along the trajectoryc) longitudinal acceleration along with the longitudinal speedd) lateral acceleration along the trajectorye) relation between longitudinal and lateral accelerationsf) absolute acceleration along the trajectory<iframe width="640" height="360" src="https://www.youtube.com/embed/1haB9LHmxzE?&amp;wmode=opaque&amp;rel=0&amp;enablejsapi=1&amp;origin=https://www.wevolver.com" frameborder="0" allowfullscreen="" class="fr-draggable" data-lf-yt-playback-inspected-kn9eq4roawkarlvp="true"></iframe> <h2 dir="ltr">What are the different applications of the technology?</h2>Planning the AV motion is characterized by using various techniques and many of which originate from the tasks of modeling trajectories for robots. The difference from planning for robots lies primarily in the fact that vehicles are high-speed unsafe transport means and the significant influence of physical characteristics of the vehicle-road interaction. Another planning option is the search for continuous functions defined in the space domain based on the optimization process in the presence of geometric, kinematic, and physical characteristics restrictions limiting the vehicle-road interaction. The root-mean-square curvature of an optimized path within the trajectory boundaries can be much less than one of a trajectory built by midpoints.The optimization settings can be tuned concerning the type of vehicle drivetrain and the presence of intelligent traction control systems. As shown in Fig. 6b, entering the second lane's corridor is possible with acceleration and deceleration. The first technique is more typical for vehicles with front-wheel drive, while the second fits rear-wheel drive. With Torque Vectoring or Sport Differential technology, the nature of the control plans can be more intense towards higher speeds and accelerations.For planning the AV kinematic parameters, it is recommended to focus on the criteria that ensure using a speed close to the desired level in a quadratic sense and a compromise between the intensities of longitudinal speeds and accelerations. The latter provides both smoothness of speed and acceleration (Fig. 6a, 6b). At the same time, it is desirable to choose the weighting coefficients' balance in such a way to preserve the physical capability of reproducing such control laws on an actual vehicle. This might occur when the transient delay problem arises due to the features of the vehicle propulsion system. If the acceleration prediction requires only non-negative values, the minimum acceleration value in the constraints must be set to a negative value close to&nbsp;0. First, this will narrow the range of scattering and search for accelerations. Second, it will exclude the variants with more significant negative acceleration values, which would mean the need for using the braking system. Thus, the weighting coefficients must correspond to the task of maintaining a speed mode.<h2 dir="ltr">How does it affect the industry and/or society?</h2>A distinctive feature of the proposed technique is an explicit restriction of the safe motion area with optimizing the best trajectory choice in contrast to the approaches focused on conjugating the lanes' midpoints by smooth curves. The fundamental advantage of the proposed approach consists of obtaining a significant number of reference curves (Fig. 6) mathematically related to each other, which contributes to improving the quality of AV control in tracking. The forecasting stability is ensured by the smoothness of the higher derivative functions of the desired trajectory and speed distributions. Furthermore, the vehicle has a sensory system (MEMS gyroscopes and accelerometers, wheels' angular speed sensors) capable of evaluating in real-time the longitudinal speed, longitudinal and lateral accelerations, yaw rate, and other parameters directly. Thus, in organizing the tracking of AV references, the control accuracy is higher than only by controlling speed and lateral position.<h2 dir="ltr">About the University Technology Exposure Program 2022</h2>Wevolver, in partnership with <a href="https://mouser.com/" target="_blank">Mouser Electronics</a> and&nbsp;<a href="https://www.ansys.com/academic" rel="noopener noreferrer" target="_blank">Ansys</a>,&nbsp;is excited to announce the launch of the University Technology Exposure Program 2022. The program aims to recognize and reward innovation from engineering students and researchers across the globe. Learn more about the program <a href="http://www.wevolver.com/student-program" target="_blank">here</a>.<img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjQ1NTUxMjQ2MTI4LUJyb3VnaHQgdG8geW91IGJ5ICgxKS5qcGciLCJlZGl0cyI6eyJyZXNpemUiOnsid2lkdGgiOjk1MCwiZml0IjoiY292ZXIifX19" style="width: 300px;" class="fr-fic fr-dib" alt="University-Technology-Exposure-Program-Mouser-Ansys-Wevolver"><h2 dir="ltr">References</h2>[1] Diachuk, M.; Easa, S.M. Motion Planning for Autonomous Vehicles Based on Sequential Optimization. Preprints 2022, 2022020165 (doi: 10.20944/preprints202202.0165.v1).

A novel mathematical approach for planning the autonomous vehicle  motion in a constrained space

Motion Planning For Autonomous Vehicles Based On Sequential Optimization

This article was discussed in our <a data-saferedirecturl="https://www.google.com/url?q=https://www.wevolver.com/profile/the.next.byte&source=gmail&ust=1640817319915000&usg=AOvVaw2nPRdRwJrXSYYeM9RCFu5x" href="https://www.wevolver.com/profile/the.next.byte" id="isPasted" rel="noopener noreferrer" target="_blank">Next Byte podcast</a>.&nbsp;<iframe height="200px" width="100%" frameborder="no" scrolling="no" seamless="" src="https://player.simplecast.com/3140758b-6aa9-46a5-829f-e13f372ed163?dark=false" class="fr-draggable"></iframe>The full article will continue below.<hr>Conventional agriculture is at a crossroads: on the one hand, consumers are becoming increasingly aware of sustainable farming methods, and on the other, the use of pesticides and fertilizers is having serious consequences for the soil. But how can farmers reconcile economic yields and ecological farming methods? Autonomous agricultural robots are seen as a promising solution here. Up-and-coming companies such as the Dutch <a href="https://pixelfarmingrobotics.com/#robot-one" id="isPasted" rel="noopener" target="_blank">Pixelfarming Robotics</a> are developing systems that have the potential to change agriculture long term. One of the keys for the global success: a smart energy system, that is tailored for agricultural applications!&nbsp;<img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjM4Mjc5ODQ2NDE1LXRvb2xzLWFncmljdWx0dXJhbC1yb2JvdGljcy1hZ3Jhcm9ib3Rlci1waXhlbGZhcm1pbmcuanBnIiwiZWRpdHMiOnsicmVzaXplIjp7IndpZHRoIjo5NTAsImZpdCI6ImNvdmVyIn19fQ==" style="width: 100%;" class="fr-fic fr-dib">Excessive fertilization and the use of pesticides are increasingly affecting farmland. Insects, small animals and microorganisms fall victim to the measures, which has serious effects on the fertility of the soil and the fertilization of the plants. Companies like Pixelfarming Robotics aim to eliminate the need for pesticides and herbicides such as glyphosate. With Robot One, they developed an all-electric agricultural robot for weed control without pesticides.&nbsp;<h2 id="isPasted">Destroy weeds without chemicals with advanced sensors</h2>Depending on the task, the autonomous smart agricultural robots can be equipped with various tools such as hooks, streamers or spikes as well as sophisticated sensors to remove weeds without the use of chemicals. A total of ten robot arms are available, replacing five pairs of hands. These are all multifunctional and individually adjustable in row width and working depth. There is also no need to compact the soil by using heavy tractors.“Agricultural robots have the potential to radically change agriculture and herald the transformation towards ecological but at the same time high-yield cultivation,” says&nbsp;Arend Koekkoek, CEO and founder of&nbsp;Pixelfarming&nbsp;Robotics.&nbsp;&nbsp;<img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjM4Mjc5ODg3NjQ3LWFncmFyb2JvdHMtYWdyYXJvYm90ZXItZXRhTElOSy0zMDAwX1dpZmVyaW9uX2VmZmljaWVudC13aXJlbGVzcy1jaGFyZ2luZy5qcGciLCJlZGl0cyI6eyJyZXNpemUiOnsid2lkdGgiOjk1MCwiZml0IjoiY292ZXIifX19" style="width: 60%;" class="fr-fic fr-dib">Wiferion’s wireless battery charger etaLINK 3000 for mobile robots works fast, powerful and reliable even under hard outdoor conditions&nbsp; <h2 id="isPasted">Special requirements for the energy supply of agricultural robots</h2>Many experts are convinced that autonomous robots like those from Pixelfarming will be plowing fields, sowing seeds and harvesting crops in the future. But operating in harsh and dirty outdoor environments places special demands on the energy supply so that the battery-powered vehicles can also reliably perform their tasks. Energy solution providers such as the Freiburg-based tech company <a href="https://www.wiferion.com/en" rel="noopener noreferrer" target="_blank">Wiferion</a> are relying on the concept of inductive energy transmission. With its “wireless charger” <a href="https://www.wiferion.com/en/products/etalink-3000-inductive-charging-with-3-kw/" rel="noopener noreferrer" target="_blank">etaLINK 3000</a>, the company is already the market leader for contactless charging of mobile robots and AGVs. Because the charging solution is an encapsulated system with IP65 certification, it is so strong that it already meets all the requirements of automated agriculture.<h2>Moisture, dust and dirt does not affect the power supply</h2>“Our&nbsp;etaLINK&nbsp;system has no open or live contacts,&nbsp;connectors or cables. Therefore, moisture, dust and dirt cannot affect the reliable power supply in any way,” explains Johannes Mayer, Managing Director&nbsp;at&nbsp;<a href="https://www.wiferion.com/en/" target="_blank" rel="noopener noreferrer"></a><a href="https://www.wiferion.com/en/" rel="noopener noreferrer" target="_blank">Wiferion</a>.In this way, Wiferion minimizes the risk of downtime. The <a href="https://www.wiferion.com/en/products/etalink-3000-inductive-charging-with-3-kw/" target="_blank">system</a> works via plug-and-play and can currently charge at 3 kW. The charger can charge all common battery types – regardless of cell chemistry. However, Wiferion’s energy experts recommend the use of Li-Ion batteries to exploit the full potential of the energy supply of the agricultural robot. That is why Wiferion is working closely with battery manufacturer VARTA, which also believes in the future trend of sustainable management of agricultural land.<div class="fr-img-space-wrap">&nbsp;<img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjM4Mjc5OTMxMDg3LVZBUl9FYXN5X0JsYWRlXyZfRWFzeV9CbG9ja19DTVlLXzIwMjAtVkFSVEExLmpwZyIsImVkaXRzIjp7InJlc2l6ZSI6eyJ3aWR0aCI6OTUwLCJmaXQiOiJjb3ZlciJ9fX0=" style="width: 80%;" class="fr-fic fr-dib">VARTA Application Specific Batteries Easy Block and Easy Blade&nbsp;</div><h2 id="isPasted">Automated and robust power supply with VARTA batteries</h2><a href="https://www.varta-ag.com/en/industry/product-solutions/lithium-ion-battery-packs/asb/easy-block" rel="noopener" target="_blank"><span data-ccp-parastyle="Formatvorlage1" data-ccp-parastyle-defn='{"ObjectId":"b923eab2-53b0-459a-af9e-42d4036cf962|184","ClassId":1073872969,"Properties":[134233614,"true",201340122,"2",201341983,"0",335559705,"1031",335559739,"0",335559740,"240",469769226,"Arial,Times New Roman",469775450,"Formatvorlage1",469777841,"Arial",469777842,"Times New Roman",469777843,"Times New Roman",469777844,"Arial",469778129,"Formatvorlage1",469778324,"Normal"]}'>VARTA</a>&nbsp;estimates that the global market for agricultural robotics will grow to around 24 billion US dollars by 2023. Demand for high-performance energy solutions for automated vehicles and robotic systems will be correspondingly high. According to&nbsp;VARTA, lithium-ion batteries for agricultural robotics applications offer several advantages over lead-acid solutions. The&nbsp;Application–Specific&nbsp;Batteries&nbsp;(ASB)&nbsp;Easy Block and Easy Blade&nbsp;developed by&nbsp;VARTA&nbsp;are lithium-ion packs for use in small and medium-sized vehicles. The batteries are modular and expandable&nbsp;and fit perfectly with the wireless charger of&nbsp;Wiferion&nbsp;to offer an automated and robust energy system for all kind of agricultural applications.&nbsp; First Published at&nbsp;<a href="https://www.wiferion.com/en/news/autonomous-agricultural-robots-revolutionize-organic-farming/" target="_blank" rel="noopener noreferrer"></a><a href="https://www.wiferion.com/en/news/autonomous-agricultural-robots-revolutionize-organic-farming/" rel="noopener noreferrer" target="_blank">wiferion.com</a>

No pesticides and herbicides anymore needed thanks to Pixelfarming Robotics and its robot » Robot One «.

Agricultural robots are the work force of tomorrow 

Autonomous agricultural robots revolutionize organic farming

Written by Alexander Diggins, Cofounder &amp; CTO, Nimbus Engineering, Inc.It’s difficult to enter a warehouse today and not observe a symphony of self-guided electric machines performing a suite of repetitive, yet mesmerizing, tasks. Typically referred to as autonomous mobile robots, or AMRs, these platforms have proven critical in sorting packages, picking items, and transporting materials within distribution centers, fulfillment centers, and even grocery stores. However, because these systems are battery operated, their supply chain participation does not come without the creation of a new set of roadblocks to overcome.Today’s mobile robots primarily use lithium-ion or lead-acid batteries, which means that at some point during the robot’s work cycle, it will need to be recharged or replaced. Downtime, or time spent charging, interrupts regular operations and negatively impacts payback period since the AMR is ‘temporarily unemployed’ during this time. A second major issue facing AMR operators is managing battery degradation which occurs after deep cycling and repeated charging. After only a few hundred charge cycles, you can expect poorer battery performance (80-90% the original capacity) and impending battery replacements.To alleviate these pain points, Nimbus Engineering has developed contact-free charging solutions for AMRs which can lessen on-board battery capacity requirements and reduce downtime from charging events. Nimbus’ Power Relay Technology (PRT) converts incident light to useful energy where and when it’s needed: <a href="https://www.youtube.com/watch?v=JwdBR3bgsm8" target="_blank">Technology Demo Video: YouTube</a>.Light weighs nothing, travels efficiently through air, and leaves nothing behind after it is switched off. Because of this, a single light emitter may be used to power several AMRs within a closed system by transmitting energy to one Relay and then quickly pivoting to power a second. This design also minimizes charging infrastructure, simplifying initial installations.<img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjM0MjU0Mjg5NDM3LVNjcmVlbiBTaG90IDIwMjEtMTAtMTQgYXQgNC4yMC41OSBQTS1taW4ucG5nIiwiZWRpdHMiOnsicmVzaXplIjp7IndpZHRoIjo5NTAsImZpdCI6ImNvdmVyIn19fQ==" style="width: 755px;" class="fr-fic fr-dib">Micro fulfillment center (MFC) concept for AutoStore scalable solution. MFCs are the ideal environment for Relays to reduce battery waste and increase robot utility.<h2 id="isPasted">The&nbsp;MFC Charging&nbsp;Problem</h2>In the case of micro fulfillment centers (MFCs), which are typically small, automated, back-of-store fulfillment centers responsible the “last mile”, an installation may have several hundred AMRs operating at once. This puts immense pressure on charging protocols, especially when handling high order volumes. In order to meet demand, an operator is faced with a trade between deploying additional robots or procuring additional batteries which are swapped when the AMR’s state-of-charge (SOC) falls below a specified level, both of which increase operating costs.Luckily, an AMR equipped with a Power Relay can achieve this same level of throughput via contact-free [wireless] charging, offsetting the AMR’s power consumption during its work cycle. A light emitter sitting on the perimeter of an MFC installation can transmit hundreds of Watts to the Power Relay-equipped AMR at the precise moment it engages a heavy load or while it moves between tasks.Without the Relay, the AMR must either charge at distinct charging locations within the MFC stack or pull over for a battery-swap, both of which decrease productivity. Relays eliminate these mechanical bottlenecks by creating a virtual [light] power cord between the emitter and the AMR, translating into higher throughputs, higher margins, and faster payback periods.<h2>What Does This Mean for Our Future?</h2>AMRs are not the only battery-electric systems that face future challenges. Electric vehicles, electric drones, and electric air taxis will invariably face the same optimization problem that arises when batteries are involved: How long will my vehicle run before it needs to stop to recharge? And how long will it need to recharge?It’s unlikely that this problem be solved with any one technology or solution. As they say, “It takes a village”. However, in conjunction with improved energy storage technologies, commercializing new methods for delivering power to mobile systems as they operate will sprout new, more flexible autonomy-focused technologies and business models.<div class="fr-img-space-wrap"><div class="fr-img-space-wrap"><img src="https://s3-us-west-1.amazonaws.com/wevolver-project-images/froala%2F1634254694909-Screen+Shot+2021-10-14+at+4.34.21+PM-min.png" style="width: 756px;" class="fr-fic fr-dib">The future of electrification will be accelerated by new energy technologies.</div></div>

Power Relay-equipped mobile robots can receive power at a distance. This eliminates the need to stop to charge, while dramatically increasing battery lifetime.

Power Relay Technology uses light to power robots enabling them to work continuously.

Powering Autonomous Robots with Light

In the manufacturing industry, motors complete the powerful task of converting electrical energy to mechanical energy. Stepper motors and Servo Motors both have distinct advantages and serve as common solutions for motion control projects. Determining the correct motor relies on specifications and application of use.&nbsp;<h2 dir="ltr" id="isPasted">Torque &amp; Speed</h2>Both types of motors have different speed and torque characteristics, this can be the deciding factor on which motor is appropriate for the application at hand. At high speeds, stepper motors typically have poor torque characteristics. On the other hand, Servo motors can generate speeds anywhere between two and four times the speed of a<a href="https://islproducts.com/component/stepper-motors/" target="_blank">&nbsp;stepper motor</a>.Servo motors operate under constant position feedback (closed-loop), as opposed to the typical open-loop system of a stepper motor. This allows servo motors to operate at higher speeds and generate higher peak torque. The use of rare-earth magnets in servos is an additional feature that enables them to create more torque in a small package.<div class="fr-img-space-wrap"><img src="https://s3-us-west-1.amazonaws.com/wevolver-project-images/froala%2F1629233415365-2.png" style="width: 300px;" class="fr-fic fr-dib" alt="Stepper Motor and Servo Motor - Torque vs Speed Graph">Stepper Motor and Servo Motor - Torque vs Speed Graph </div><h2 dir="ltr" id="isPasted">System Control</h2>Usually, stepper motors operate in the open-loop, constant current mode. Stepper motor systems operating in a constant current mode (open loop) creates a significant amount of heat in both the motor and drive, which is a concern for some. Servo control solves this by only supplying the motor current required to move or hold the load.<a href="https://islproducts.com/component/dc-servo-motors/" target="_blank">Servo motors</a> operate with a closed-loop system. Closed-loop control systems have encoders (sensors) to provide feedback. Feedback is data that is passed back from some point into the control system to another preceding point in the control system. Servos are controlled by sending an electrical pulse of variable width, known as pulse width modulation. When the system receives a pulse of some length it will then rotate the motor accordingly.<h2 dir="ltr">Pole Count</h2>Stepper motors generally use 50 to 100 poles, whereas servo motors only use between 4 and 12 poles. A pole refers to the area of a motor where a North or South Pole is generated by a permanent magnet or by passing current through coils of a winding. Each pole offers a natural stepping point for the motor shaft.The high pole count of steppers allows them to generate holding torque, and consume less power at zero speed. Steppers don’t require encoders since they can accurately move between their many poles whereas servos, with fewer poles, require an encoder to keep track of their position.<h2 dir="ltr">Cost Analysis</h2>Servo motors use rare-earth magnets and also have external features such as an encoder causing a higher cost. The physical size of a servo motor is larger than a stepper motor, requiring more raw materials to be manufactured.Stepper motors are significantly less intricate. Stepper control systems are always less expensive and are optimal for applications that require low-to-medium acceleration, high holding torque, and the flexibility of open or closed-loop operation.Servo motors are more costly due to the complexity of their internal design. Stepper motors use less expensive magnets and rarely incorporate gearboxes.<h2 dir="ltr">Which Motor Fits Your Application the Best?</h2>Stepper motors are a good candidate for applications that require simple motion and no feedback. Steppers are available in a large variety of sizes, which helps to accommodate for size constraints.Servo motors aid applications where sound and vibration need to be minimal. Servo motors are better for complex systems that require precise feedback. Certain applications such as CNC machinery require high accuracy, where a servo motor is an optimal solution. Servo motors are more efficient than stepper motors, with efficiencies between 80-90%.In overall performance, servo motors are best for high speed, high torque applications while stepper motors are better suited for lower acceleration, high holding torque applications. ISL Products can help tailor the correct motor for all applications, small or large.The table below will help you determine which motor to choose based on your application requirements.<div class="fr-img-space-wrap"><img src="https://s3-us-west-1.amazonaws.com/wevolver-project-images/froala%2F1629233534631-3.png" style="width: 300px;" class="fr-fic fr-dib">Application Attributes for Stepper Motors vs Servo Motors </div>

What differentiates these two types of motors and how to determine which is the best fit for your application. 

Servo Motors vs. Stepper Motors

<h2 dir="ltr" id="isPasted">What is a Stepper Motor?</h2>A stepper motor is a type of brushless DC electric motor that moves in precise angles, called steps, by converting a series of electrical pulses into rotational motion. They will not produce continuous motion from a continuous input voltage, and it will stay at a particular position as long as the power is “on”.&nbsp;<a href="https://islproducts.com/component/stepper-motors/" rel="noopener noreferrer" target="_blank">Stepper motors&nbsp;</a>are controlled with the use of discrete electrical pulse signals. Each pulse will rotate the step motor shaft by a fixed angle called a “step”. ISL Products can offer stepper motors with several different step angles (0.45°, 0.9°, 1.8°). ISL offers a concierge approach, ensuring that our Stepper Motors perform as intended within your application. You can learn more about our dedicated approach by reading our recent<a href="https://islproducts.com/case-study/stepper-motor-for-automated-retail-vending-machines/" target="_blank">&nbsp;stepper motor case study</a>.If the pulses are carried out in a specified sequence, the motor will spin continuously; the speed can be controlled by the rate at which the pulses are sent. These natural step angles allow a stepper motor to be accurately positioned without the accumulation of error.&nbsp;The stepper motor produces output torque from the interaction between the magnetic field in the rotor and in the stator. The magnetic field strength is proportional to the amount of current applied to the windings as well as the amount of turns within the windings.Stepper motors fill a unique niche in the motor control world. These motors are commonly used in measurement and control applications throughout various industries. Sample applications include Ink Jet Printers, CNC machines, 3D Printers, Automation &amp; Packaging machines, Security &amp; Surveillance systems, Medical Tools &amp; Equipment, Robotics and Vending machines.&nbsp;<h2 dir="ltr">Stepper Motor Construction</h2>A<a href="https://islproducts.com/component/stepper-motors/" target="_blank">&nbsp;stepper motor</a> consists of a permanent magnet sandwiched between the two rotor halves (causing axial polarity), which make up the spinning part of the motor. That is placed into a stator housing where the stator coils of wire make up the different motor phases. With a 2 phase stepper motor, each phase has four coils. The phase is magnetized where the A and A- phases (or B and B-)are magnetized at the same time so that both A phases are magnetized as one pole, and both A- phases are magnetized as the opposite pole. This is because the winding direction of the A-phase is opposite to the winding direction of the A- phase.&nbsp;<div class="fr-img-space-wrap"><img alt="Stepper Motor Construction" src="https://s3-us-west-1.amazonaws.com/wevolver-project-images/froala%2F1628191590946-Wevolver+Stepper+Motor+Fundamentals.png" class="fr-fic fr-dii">Stepper Motor Construction </div>The rotor is connected to the motor shaft, which gives the output rotation and torque of the motor when voltage and current pulses are applied to the motor windings. The bearings on either side of the rotor allow for smooth rotation with little friction and wearing. The bearings are placed into their designated spaces in the front and rear end caps, which allow for the concentricity of the rotor inside the stator. Perfect alignment of the rotor and the stator is very important because the air gap between them, where the motor torque is generated, must be equal on all sides and is only a few nanometers wide – thinner than a strand of hair.&nbsp;<h2 dir="ltr">Unique Features &amp; Advantages of Stepper Motors</h2><ul><li dir="ltr">Brushless – Stepper motors are brushless, which means they have a high reliability with little maintenance. The commutator and brushes of conventional motors are some of the most failure-prone components, and they create electrical arcs that are undesirable or dangerous in some environments.</li><li dir="ltr">Load Independent – Stepper motors will turn at a set speed regardless of load as long as the load does not exceed the torque rating for the motor.</li><li dir="ltr">Open Loop Operation – Stepper motors move in quantified increments or steps. As long as the motor runs within its torque specification, the position of the shaft is known at all times without the need for a feedback mechanism.</li><li dir="ltr">Holding Torque – Stepper motors are able to hold the shaft stationary.</li><li dir="ltr">Excellent response to start-up, stopping and reverse.</li><li dir="ltr">Inherently more fail safe than servo controlled motors.</li></ul>ISL Products can help to answer any questions related to stepper motors. <a href="https://islproducts.com/contact/" rel="noopener noreferrer" target="_blank">Contact an applications engineer </a>today.

Everything you need to know about Stepper Motors.... and more! 

Stepper Motor Fundamentals

<h2 dir="ltr" id="isPasted">Enhancing the Motor Selection Process</h2>At any stage throughout your DC motor selection process, you can benefit from collaborating with an application engineer to ensure your provided with the optimal dc motor solution. Early engagement with an applications engineer has been proven to save design engineers valuable time throughout the entire motor selection process. When your application requires a DC motor or gear motor, contact an applications engineer as early in the design process as possible for maximum benefit.Your timeline and expectations are very important. The first step an application engineer will take is to learn about your project’s timeline ensuring all items are delivered in a timely manner. On average, engineers save over 10 hours of research time during their motor selection process by speaking with an ISL Products applications engineer.<img alt="Graph showing added value of early engagement dc motors" src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjI2ODk5OTE2NTMxLVdlYnNpdGUgQXBwIEVuZy4gQmVuZWZpdHMgLSBNb3RvcnMucG5nIiwiZWRpdHMiOnsicmVzaXplIjp7IndpZHRoIjo5NTAsImZpdCI6ImNvdmVyIn19fQ==" class="fr-fic fr-dii"><h2 dir="ltr">Start the Discussion with an Applications Engineer</h2>An application engineer will ask some preliminary questions to learn more about your application and motor requirements in order to provide the optimal motor solution. Some common questions they may ask you early in the design process are:<ul><li dir="ltr">What<a href="https://islproducts.com/dc-motors-and-dc-gear-motors/" target="_blank">&nbsp;</a>type of motor are you interested in: brushed, brushless (BLDC), stepper, etc.?</li><li dir="ltr">Are you considering a<a href="https://islproducts.com/design-note/planetary-gear-motors-vs-spur-gear-motors/" target="_blank">&nbsp;gear motor</a> for additional torque output?</li><li dir="ltr">Do you have any preliminary application data that may benefit us in the motor selection process?</li><li dir="ltr">What are some of the more critical motor parameters that we should be aware of?</li></ul>Once these questions are answered, the applications engineer will analyze your requirements and provide a preliminary motor solution. For an even faster process, submit the information through ISL's <a href="https://islproducts.com/motors-selection-guide-specification-upload/" target="_blank">Motor Selection Guide</a> so our applications engineers can look over the data before the first call or email.&nbsp;<h2 dir="ltr">Preliminary Design Specifications</h2>Preliminary design specifications will include an overall dimensional drawing and motor performance curves. Our proprietary motor simulation software allows us to provide projected performance data very early on in the motor selection process, even before a sample is made.A motor / gear motor design database helps an application engineer streamline the selection process even further. They have the ability to cross-reference your requirements to pre-existing designs, making the design process much quicker. If slight alterations are needed to meet your specific requirements they will make those adjustments.<h2 dir="ltr">Parameters to Consider During Motor Selection</h2><h3 dir="ltr">Torque &amp; Speed</h3>The two most important parameters when selecting a motor are the torque and speed. More specifically, the torque and speed you would like the motor to operate at under the anticipated load. The option of adding a gear head to the motor will significantly increase the torque available but reduce the speed.<h3 dir="ltr">Voltage &amp; Current Draw</h3>When dealing with any DC powered device, understanding the available voltage is important. The voltage will dictate a lot about a motor’s internal design characteristics. Once the voltage is determined, another parameter to consider is the current draw. Current draw becomes a more important factor if the device is battery powered. If you’re using a constant power source, the current draw may not be as critical. Understanding these electrical parameters helps the applications engineer get a feel for the overall power available.<h3 dir="ltr">Understanding the Data</h3>It’s very important that you understand the data that is provided to you as well as your application’s requirements. All of these are crucial in the design and performance of your application or device. An apps engineers will help to educate you and answer any questions throughout the entire process.<h2 dir="ltr">Application Requirements &amp; Design Considerations</h2>Providing application duty cycle information to an apps engineer will give ample insight on how the motor will be expected to perform. When discussing duty cycle, you should mention if the motor will be running continuously or intermittently. If a duty cycle is intermittent, how long will it operate (ON time) and what is the rest period in between (OFF time)? Will the motor be changing rotational direction? If so, make sure there is enough dwell time in between changes in direction.With the use of in-house motor test equipment dc motor manufacturers are able to accurately simulate your expected duty cycle and provide useful insight on how a specific motor will perform. This equipment also allows manufacturers to generate performance curves illustrating the speed, torque, current draw and power of a motor from no-load to stall. All of these figures can be signed off on before moving onto mass production, ensuring you get exactly what you need.<h2 dir="ltr">Dedicated Service After The Selection Process</h2>Even after the motor selection process is complete, our dedicated team of application engineers are still working to provide you with the most optimal components. Our post-production quality testing ensures our motors meet or exceed your expectations before the motors arrive at your facility.Our goal is to make the overall motor selection process quick and exciting for you and your team. We are able to accomplish this by providing valuable insight from many years of experience and by serving as an extension of your engineering team. Get started, <a href="https://islproducts.com/contact/" target="_blank">reach out to an Applications Engineer today</a>!

Early Engagement Benefits with an Applications Engineer

Save valuable time by discussing your dc motor requirements early in the design process with an applications engineer.


Benefits of Early Engagement With an Applications Engineer: DC Motors and Gear Motors

<h2 dir="ltr" id="isPasted">What is a DC Motor?</h2>A Direct Current (DC) motor is a rotating electrical device that converts direct current electrical energy into mechanical energy. An Inductor (coil) inside the DC motor produces a magnetic field that creates rotary motion as voltage is applied to its terminal. Inside the motor is an iron shaft, wrapped in a coil of wire. This shaft contains two fixed magnets, North and South, on each side which causes both a repulsive and attractive force, producing torque. <img alt="Inside the DC Motor" src="https://s3-us-west-1.amazonaws.com/wevolver-project-images/froala%2F1625081828033-Fig+1+-+2.png" class="fr-fic fr-dii" style="width: 778px; height: 346.978px;" width="624"><h2 dir="ltr">What is a DC Gear Motor?</h2>A gear motor is an all-in-one combination of a motor and gearbox. The addition of a gear head to a motor reduces the speed while increasing the torque output. The most important parameters in regards to gear motors are speed (rpm), torque (lb-in), and efficiency (%). In order to select the most suitable gear motor for your application you must first compute the load, speed and torque requirements for your application. Not all gear motors are the same. There are <a href="https://islproducts.com/component/spur-gear-motors/" target="_blank">Spur Gear Motors</a>,<a href="https://islproducts.com/component/planetary-gear-motors/" target="_blank">&nbsp;Planetary Gear Motors</a> and<a href="https://islproducts.com/component/worm-gear-motors/" target="_blank">&nbsp;Worm Gear Motors</a>, each one excelling at a different task. Read our article, <a href="https://www.wevolver.com/article/the-motors-inside-autonomous-robots" target="_blank">The Motors Inside Autonomous Robots</a>, to get a better understanding of these different types of gear motors.&nbsp; <div class="fr-img-space-wrap"><img alt="DC Gear Motor Construction" src="https://s3-us-west-1.amazonaws.com/wevolver-project-images/froala%2F1625082292903-Wevolver+Body+DC+Motor+Basics.png" class="fr-fic fr-dii" style="width: 513px;"></div>&nbsp;<h2 dir="ltr">The Motor Selection Process</h2>The motor selection process, at the conceptual design phase, can be challenging. The following key points can help you determine and select the most appropriate motor or gear motor for our application.<ol><li dir="ltr">Design Requirements&nbsp;–&nbsp;A design assessment phase where the product development requirements, design parameters, device functionality, and product optimization are studied.</li><li dir="ltr">Design Calculations&nbsp;–&nbsp;Calculations used to determine which motor would be the best solution for your application. Design calculations determine gear ratio, torque, rotating mass, service factor, overhung load, and testing analysis.</li><li dir="ltr">Types of DC Motors/Gear motors – The most common electrical motors convert electrical energy to mechanical energy. These types of motors are powered by direct current (DC).<ul><li dir="ltr"><a href="https://islproducts.com/component/brushed-dc-motors/" target="_blank">Brushed</a></li><li dir="ltr"><a href="https://islproducts.com/component/brushless-dc-motors/" target="_blank">Brushless</a> (BLDC)</li><li dir="ltr"><a href="https://islproducts.com/component/planetary-gear-motors/" target="_blank">Planetary Gear Motors</a></li><li dir="ltr"><a href="https://islproducts.com/component/spur-gear-motors/" target="_blank">Spur Gear Motors</a></li><li dir="ltr"><a href="https://islproducts.com/component/stepper-motors/" target="_blank">Stepper</a></li><li dir="ltr"><a href="https://islproducts.com/component/coreless-brushed-dc-motors/" target="_blank">Coreless</a> &amp; <a href="https://islproducts.com/component/coreless-brushless-dc-motors/" target="_blank">Coreless Brushless</a></li><li dir="ltr"><a href="https://islproducts.com/component/dc-servo-motors/" target="_blank">Servo</a></li></ul></li></ol> <ol start="4"><li dir="ltr">Motor Specifications&nbsp;– Once the design calculations are performed, and the application parameters are defined, you can use this data to determine which motor or gear motor will best fit your application. Some of the most common specs to consider when selecting a motor or gear motor would be:<ul><li dir="ltr">Voltage</li><li dir="ltr">Current</li><li dir="ltr">Power</li><li dir="ltr">Torque</li><li dir="ltr">RPM</li><li dir="ltr">Life Expectancy / Duty Cycle</li><li dir="ltr">Rotation (CW or CCW)&nbsp;</li><li dir="ltr">Change in Rotation / Dwell Time</li><li dir="ltr">Shaft Diameter and Length</li><li dir="ltr">Enclosure Restrictions</li></ul></li></ol><h2 dir="ltr">Gear Motor Performance Curves</h2>A motor's performance and gearbox performance are combined into one graph by displaying three specific parameters. These three parameters are speed, torque and efficiency. These performance curves are essential when selecting a gear motor for your application.<img alt="Gear Motor Performance Curves" src="https://s3-us-west-1.amazonaws.com/wevolver-project-images/froala%2F1625082139276-1.png" class="fr-fic fr-dii">&nbsp;<ul><li dir="ltr">Speed/Revolutions&nbsp;(N) – (unit: rpm)&nbsp;indicated as a straight line that shows the relationship between the gear motors torque and speed. This line will shift laterally depending on voltage increase or decrease.</li><li dir="ltr">Efficiency&nbsp;(η) – (unit: %)&nbsp;is calculated by the input and output values, represented by the dashed line. To maximize the gear motors potential it should be used near its peak efficiency.</li><li dir="ltr">Torque&nbsp;(T) – (unit: gf-cm)&nbsp;this is the load borne by the motor shaft, represented on the X-axis.</li><li dir="ltr">Current&nbsp;(I) – (unit: A)&nbsp;indicated by a straight line, from no load to full motor lock. This shows the relationship between amperage and torque.</li><li dir="ltr">Output&nbsp;(P) –&nbsp;(unit: W)&nbsp;is the amount of mechanical energy the gear motor puts out.</li></ul>For example, let’s consider the performance curve below&nbsp;(figure 5)&nbsp;for a DC gear motor.<ul><li dir="ltr">Maximum operating efficiency (70%) for this motor would occur at 3.75 lb-in / 2,100 rpm.</li><li dir="ltr">As torque increases the speed and efficiency decrease. The result of increased torque is poor output performance and the device will eventually fail to function once the motor reaches its stall torque (18 lb-in).</li></ul>&nbsp;<div class="fr-img-space-wrap"><img alt="DC Gear Motor Torque Performance Curves" src="https://s3-us-west-1.amazonaws.com/wevolver-project-images/froala%2F1625082178768-2.png" class="fr-fic fr-dii" style="width: 548px;"></div>&nbsp;Gear motor performance curves are a helpful tool when selecting a motor for your application. To get the most out of the performance curves it’s important to thoroughly understand the application's requirements. You can use your load and speed requirements to help determine the required torque. Most DC motor and gear motor manufacturers provide performance curves upon request.

Autonomous Ground Vehicles (AGVs)