Tag Archives: Autonomous Robot

Encoders for Autonomous Mobile Robots

Whether it is AMR or autonomous mobile robots, AGC or automated guided carts, AGV or automated guided vehicles, various types of robots or robotics are increasingly important to the industry. They use these robots to move parts and materials from one place to another in every environment. For instance, goods move from manufacturing to warehouse, and thence to grocery stores to face customers.

It is important that these automated machines work correctly because precision is a vital requirement. This requires reliable motion feedback to the controllers. This is where encoders come in. For instance, autonomous motion applications requiring motion feedback are useful in steering assembly, drive motors, lift controls, and more.

The industry uses several automated carts and vehicles. They use them for lifting products and materials onto and from shelves and floors in warehouses and other storage areas. To do that reliably and repeatedly, these machines require accurate and precise motion feedback. This ensures that materials and products reach where they need to go, without incurring damages.

The Encoder Product Company offers to draw wire solutions, and encoders with rack-and-pinion gears provide reliable motion feedback. This ensures all lifts stop at the right locations, thereby moving materials and products safely to their destinations. Their motion feedback options for lift control involve Model LCX, for high performance with absolute feedback option, and Model TR2, a rack-and-pinion gear as an all-in-one unit.

The Model LCX135 is one of a draw wire series, providing an excellent solution for the control of lifts. Internally, incremental and absolute encoders provide excellent lift control feedback using the CANopen communication protocol.

Automated carts and vehicles require drive motor feedback. As they move around facilities like warehouses, the controller in these vehicles needs reliable motion feedback to ensure the motors are in the proper transit areas/corridors designated for them. The motion feedback also ensures they stop and start accurately.

Motion feedback devices from the Encoder Product Company provide this reliable, repeatable motion feedback. Their Model 15T/H is a compact and high-performance encoder. It is available in the blind-hollow bore or thru-bore designs. The Model 260 is a more economical and compact encoder with a large thru-bore design. The next model 25T/H is a high-performance 2.5” encoder. While Models 25T and 260 are incremental encoders, absolute encoders are also available, and they use the same CANopen communication protocol.

To ensure the correct drive path ad steering angle, the steering assembly also needs to provide precision feedback. Absolute encoders provide the best way to ensure proper motion feedback for these steering assemblies. This is because with absolute encoders it is possible to ensure smart positioning while providing the exact location while in a 360-degree rotation.

The Encoder Product Company offers several absolute encoders. Among them is the Model A36HB, a compact absolute encoder with a 36 mm blind hollow bore. Another is the Model A58HB, an absolute encoder with a 58 mm blind hollow bore.

Where safety is considered paramount, the Encoder Product Company offers redundant encoders. These are simple solutions and economical also. Using redundant encoders allows the application to rely on different technologies, ensuring at least one encoder will continue to function even when the other has failed.

Developments in Autonomous Robots

The recent COVID pandemic had put a lid on air travel. But that is now slowly lifting, and more people are venturing out. Airports are responding with new robots offering food delivery services.

The International airport in Northern Kentucky is currently using these Ottobots, made by Ottonomy, a robotics company. The Ottobot is a four-wheeled autonomous robot.

At the airport, in the Concourse 8 area, travelers can use a dedicated app to purchase food, beverages, or travel products from select stores. The location of these stores may be anywhere in the airport. Once the travelers have placed their orders, staff, at the store, place the items within the cargo compartment of the Ottobot and send them on their way.

While making its way through the airport, the Ottobot robot uses sensors and a LIDAR module to avoid people and obstacles. Ottonomy has designed a contextual mobility navigation system for the robots to allow them to keep track of their whereabouts. Apart from the contextual mobility navigation system, the robots also use other indoor navigational systems like Bluetooth beacons, readable QR codes, and Wi-Fi signals.

Customers can see the Ottobot on their mobiles, thanks to the app, which alerts them once it reaches their location. The app also has a QR code specific to their order. Once the customer holds their QR code for the robot to scan, it unlocks and opens its cargo compartment lid to allow them to retrieve their purchase. User feedback from a pilot project in the airport helped design the current robotic delivery system.

Not only in airports but there are several urban delivery robots also that use four wheels to move along city sidewalks. The wheels are special, as they can pivot and are mounted on articulated legs.

Delivery robots usually have smart lockable cargo boxes and two sets of powered wheels on their bottom. While autonomously moving along a smooth pathway, this arrangement works fine. However, for moving over curbs, climbing upstairs, or for traversing regular obstacles.

Piezo Sonic, a Japanese robotics company, has developed Mighty, the special delivery robot. They have based their design on a concept for robots exploring the moon:—: it does not have smooth sidewalks.

Mighty has four independently powered wheels. They can point either straight ahead for normal movements, or pivot to point sideways to allow the robot to move sideways in one direction or the other. The four wheels can also pivot part of the way outward or inward, forming a circle for Mighty to spin around on the spot.

Additionally, each wheel has its own hinged leg. Therefore, when the robot moves over an uneven surface, each leg can bend independently to compensate for the difference in height. This helps to keep the main body of the bot level. Mighty can use this feature to climb shallow sets of stairs.

Mighty uses GPS to navigate cities like other delivery robots. It also has cameras and LIDAR sensors for dodging hazards and pedestrians. It can easily carry a 20-kg cargo, climb 15-degree slopes, and step over obstacles up to 15 cm tall, all the while attaining a top speed of 10 km per hour.

An Autonomous Robot Called Bat Bot or B2

Although detested and at the same time revered by people all over the world, bats are undoubtedly remarkable creatures when it comes to their ability to fly. While birds do perform the most nimble aerobatics, and most fishes swim superbly in water, bats possess the most refined powered flight mechanism, unmatched in the animal kingdom. Now a team of scientists has studied the way bats fly, and have built the first robot to mimic their flight mechanism. They have named the robot Bat Bot, or B2.

The scientists had a tough time when they tried to imitate the natural flight of a bat. Bats have flexible membranes on their wings, and use more than 40 active and passive joints with each flap of their wings. Moreover, they have bones with the capability to deform each time the bat beats its wings. The scientists found it very difficult to replicate the complete suite of biological tricks that bats use regularly.

In creating the Bat Bot, the scientists have achieved an engineering marvel. The Bat Bot weighs only about 94 grams—about as heavy as two golf balls. It has a carbon-fiber skeleton with a head filled with its on-board computer and sensors. The five micro-sized motors are strung along its backbone, and the entire skeletal structure has a silicone membrane stretched over it. A trio of roboticists at Caltech, led by Soon-Jo Chung, designed the Bat Bot capable of autonomous flapping flight. They unveiled it in the journal Science Robotics. At present, Bat Bot can perform only four main components of the movements of a bat’s wing—the shoulder, elbow, wrist bend, and the side-to-side tail swish.

According to Chung, his team had to give up the thought of simply mechanizing the flapping wings of a bat, joint by joint. They quickly understood the impossible task of incorporating all the forty joints in the design of Bat Bot, as it would only have resulted in a heavy robot, incapable of any type of flight.

After a careful study of a bat’s flight mechanism, including the biological studies documented by Dan Riskin of the Discovery Channel, the team tried to understand, among the 40 joints, those absolutely vital for the flight. Finally, they settled on a total of nine joints for the Bat Bot.

Although the Bat Bot is a sophisticated and advanced piece of machinery, it is still a very simple bat compared to the natural animal. For instance, Bat Bot does not have knuckles or joints in its carbon fiber fingers, and Bat Bot cannot actively twist its wrists that normal bats can do naturally.

Chung’s team had to make additional simplifications as well. For instance, the hyper-thin silicon membrane of Bat Bot has uniform flexibility, whereas the wing membrane of an actual bat has variable levels of stiffness in different places.

In spite of the above differences, Bat Bot does make elegant flights, almost indistinguishable from that of its biological cousin. While gliding through the air, Bat Bot has grace and fluidity, independently tucking and extending its wrists, shoulders, elbows, and legs.