Electronic Design
Science Fiction Meets Science Fact In Today’s Robot Research

Science Fiction Meets Science Fact In Today’s Robot Research

Real robots have captured the imagination of young and old engineers, designers, and programmers alike. For example, techies can get their hands dirty with iRobot’s Roomba Create or take part in competitions like FIRST Robotics. Robots also are changing how war is waged and how we protect people on and off the battlefield. And, they’re working with doctors and patients. Though we’re far from the intelligent androids found in science fiction, robot deployment and purchases are on the rise.

Still, humanoid-like robots continue to drive research and development. One such project has kept graduate students at Mälardalen University in Sweden on the run to keep up with their latest creation, nicknamed Dasher (Fig. 1). Led by Prof. Lars Asplund, a team of 21 students created Dasher using a combination of electronics, hydraulics, and an exoskeleton made of titanium tubes. Overall, it’s comparable to a human in size and stride.

Dasher is designed to run so it forgoes features such as hands, though it has arms for balance. It employs the prosthetic lower leg technology utilized by Paralympics runner Oscar Pistorius. This technology was supplied by the Icelandic company Össur, which also equipped Pistorius with his prosthetic limbs.

These design choices reduced the complexity of an already ambitious project while retaining the basic charge of developing a robot that could run using its own locomotion and balance. The team’s choice of Adacore’s GNAT Ada tool suite as the programming system was critical to delivering a workable system as well.

Ada’s Ravenscar tasking profile, a subset of the Ada language, allowed Dasher to meet the real-time requirements. Automated development tools were created to transform the Ada code into timed automata that were then analyzed by the formal verifier UPPAAL.

The Ada applications are hosted on a centralized Freescale PowerPC card that runs the Wind River Systems VxWorks real-time operating system (RTOS). Each arm and leg has its own 8-bit Atmel AT90CAN128 controller-area-network (CAN) microcontrollers that connect to the PowerPC via a CAN bus. The smaller micros manage the hydraulic servos and the dc motors, and the larger micros drive the hydraulic compressor.

The dual-camera vision system and three-axis gyroscope drive a Xilinx XC2V8000 Virtex II FPGA, which handles real-time image and distance recognition to recognize the two white lines on a running track. The goal is to have Dasher run, not walk, on its own around a track. It should finish a 100-yard dash in 9.5 seconds.

ROBOTIC STAND-INS
HRP-4C sounds like a partner for C-3PO (Fig. 2). But this robot is a more lifelike creation from the Humanoid Research Group, which is part of the Intelligent Systems Research Institute of the National Institute of Advanced Industrial Science and Technology (AIST). It stands 158 cm tall and weighs 43 kg, including the battery. The physical dimensions and structure were based on an average young Japanese female. HRP-4C was developed as part of the User Centered Robot Open Architecture (UCROA).

Its movement and walking motion, based on motion-capture, is designed to mimic a person’s gait and gestures. It also includes speech recognition and voice synthesis. The robot is intended for applications in the entertainment industry, including use at fashion shows. In fact, it appeared at one held during the Eighth Japan Fashion Week in Tokyo this year.

WowWee’s feminine Femisapien (cover image) and hunky Joebot (Fig. 3) are smaller than HRP-4C. They also cost less than $100, while the HRP-4C specs out around $200,000. Joebot is the newer and more capable of the pair, but both walk and talk. They have different levels of voice recognition, with Joebot responding to key phrases. Joebot uses IR sensors for obstacle recognition. Each robot has limited programmability, too.

WowWee also has a telepresence robot called Rovio (Fig. 4). This Wi-Fi-enabled robot can be controlled by most Web-enabled devices, from a PC to a cell phone. It even has Universal Plug and Play (UPnP) support. The head-mounted movable camera has a resolution of 640 by 480. There’s even a new LED headlight option for operation in dimly lit areas.

The Rovio is very mobile with its omnidirectional wheels. A TrueTrack Navigation System enables it to locate objects within its environment. IR sensors are used for obstacle avoidance. Rovio has its own docking station and can automatically find its way home to recharge its nickel metal-hydride (NiMH) batteries. The robot is programmable, allowing it to follow pre-programmed paths, and can be remote controlled. The Web-based application programming interface (API) is available for download.

Anybot’s Anybot QA telepresence robot is more like a cross between Venus de Milo and Disney’s Wall-E (Fig. 5). It was seen wandering around this year’s Consumer Electronics Show (see “See CES From Another Point Of View). The Anybot QA isn’t articulated. Rather, it balances atop a pair of wheels, providing an efficient mobile platform. Balancing doesn’t take a lot of power, and turning in tight places with a pair of wheels is almost trivial. The Anybot QA strolls along at up to 6 mph.

This robot uses a Wi-Fi or 3G cellular connection to exchange audio and video with its controller. A pair of 5-Mpixel cameras captures local video while a 7-in. LCD displays video at the controller’s end. Forward-looking light detection and ranging (LIDAR) is used for obstacle recognition. A green laser pointer eliminates the need for hands and arms to point at objects.

The 30-lb robot runs off a set of lithium-ion (Li-ion) batteries. Runtime is four to six hours. The control software runs on a PC or Mac with audio and webcam support. Also, the Anybot QA stands about 5 ft tall and has just two joints. One is for the head, which tilts forward, and the other is in the lower middle for balance.

ROBOTS TO THE RESCUE
The robots from Vecna Technologies provide more than a point of presence. For example, the QC Bot is designed as a hospital courier with a carrier and LCD touchscreen that can deliver material to hospital staff. It has eight motorized locking drawers and can use radio-frequency identification (RFID) or barcodes to identify users and locations.

Also, the company built the Battlefield Extraction And Retrieval (BEAR) robot for the U.S. Army’s Telemedicine and Advanced Technology Research Center (TATRC), which is part of the U.S. Army Medical Research and Material Command (USAMRMC). Among other tasks, BEAR can retrieve injured people from the battlefield or other hazardous areas like mines (Fig. 6).

Lifting and moving objects that weigh hundreds of pounds, such as a fully equipped soldier, requires significant strength and balance. But BEAR, which is 6.5 ft tall and weighs 500 lb, is up to the task. It also can handle more mundane chores such as loading trucks and delivering inventory, since pallets aren’t always the best option. Micro hydraulic valves and related systems were developed to handle the fine movement required by the system.

The BEAR rides on a set of independent tracked “legs.” Each part of the upper and lower leg has its own track. The tracks are motorized, and hydraulics handle the upper-body joint movement. BEAR also has a pivoting torso and a pair of arms that can lift its own body weight and curl 250 lb. The use of two arms is key to manipulating heavy items, which a single-arm system would have a difficult time handling.

The system uses dynamic balancing. This allows BEAR to remain stable even when balancing on its “ankles” (standing upright) and “knees” (kneeling), which are part of the multitrack system. Also, it can fold down so it’s low to the ground. It exhibits speed and good stability in almost all positions, particularly when the longer part of the tracks are in contact with the ground.

BEAR can handle other robotic chores, such as surveillance and reconnaissance, as well as explosive ordnance disposal (EOD). Specialized robots are often more economical in many instances, but the flexibility and performance that BEAR offers will make it a good option. For example, many single-arm EOD robots have been used effectively in the field to disarm bombs. An added benefit of BEAR is its ability to move heavy devices if necessary.

The goal of the project is to deliver a semi-automonous robot. BEAR can currently handle standard tasks such as balancing and righting itself using its arms when falling over. Programming the intelligence needed for more advanced operation will be a challenge, but somewhat useless without suitable hardware. Right now, it looks like BEAR will deliver the mobility and lift capacity necessary for the desired tasks.

ROBOTIC MOBILITY
“Most people think of Honda as an automobile company, but the company’s main focus has and always will be human mobility,” says Honda spokesperson Alicia Jones. “Honda has introduced two experimental walking-assist devices to help individuals achieve a new freedom of motion. The cumulative study of human walking, along with research and development of technologies conducted for Honda’s advanced humanoid robot, ASIMO, have made these walking-assist developments possible.”

ASIMO tops out at just over 4 ft and weighs about 120 lb (see “Attack Of The Humanoid Robots). It can run (Fig. 7) and walk and features 34° of freedom (DOF). It has an impressive, albeit costly, history for a nine-year-old. Nonetheless, it also has yielded significant advances in robotics. Furthermore, it has led to some potential products, such as the experimental

Stride Management Assist (Fig. 8a). This exoskeleton is designed to assist people who have weakened leg muscles but can still walk on their own. It helps extend the user’s movement to a normal stride and rate using information obtained from the leg’s movement. It’s attached to the user with a set of belts, and it can be worn easily even while sitting.

The Walking Assist Device with Body Weight Supporter provides additional lift to the user (Fig. 8b). Like the Stride Management Assist, it can be used for physical therapy. Again, those with weakened leg muscles can use the device to perform more physically demanding activities that would otherwise be next to impossible.

The system includes shoes and legs that deliver vertical support to the user’s center of gravity literally via the seat of the pants. It reduces load on the legs and joints, but doesn’t require belts or other attachments other than the shoes. The system including batteries weighs only 6.5 kg. The two motors can run for up to two hours per charge.

Both devices are essentially specialized robots designed to assist their human partner. The walking device needs to track foot and leg position so it knows how and where to provide movement and support. It can reduce load on the body when walking on level ground and on stairs. Users can even get into a semicrouch position.

The devices are designed to be easy to wear with no real training required. They will have a substantial impact on the medical and geriatric community if they become generally available, though there are no such plans yet.

ROBOTIC UNICYCLE
The two-wheeled Segway Personal Transporter has been around for some time as a robotics platform (see “Smart Motion Makes For A Smarter Design). The line of Robotic Mobility Platform (RMP) vehicles from Segway includes the RMP 200 (Fig. 9). A popular platform for robotics research, the vehicle uses a similar balancing approach to the Anybot QA.

Honda’s experimental U3X unicycle uses only a single Honda Omni-Traction (HOT) drive system (Fig. 10). The compact device fits comfortably between the rider’s legs. The HOT drive lets it move forward, backward, side to side, and diagonally. It was developed through the ASIMO robotics research.

The U3X operates like the Segway, with the rider leaning the upper body to shift body weight. The U3X’s user friendly design places the rider at roughly the same eye level as other people or pedestrians. It has a set of fold-down footrests, allowing riders to easily put their foot down when at rest or to dismount.

As with other balancing robots, the U3X uses microelectromechanical systems (MEMS) sensors and high-performance processors to determine the rider’s intention based on the weight shift. The HOT drive system employs the typical omnidirectional wheel within a wheel. Essentially, the larger primary wheel has a set of smaller wheels along its perimeter. This allows the side-toside and diagonal movement.

The experimental U3X is 65 cm high and weighs less than 10 kg, including the Li-ion battery. This permits it to operate for up to one hour. The frame is a lightweight monocoque body that includes a foldable seat, footrests, and body cover. The cover also functions as the frame and is stored in the body, making the convenient system highly portable. We will likely see more robots based on this kind of platform down the road.

Mobile and humanoid robots are becoming more commonplace and more sophisticated as time goes on. The research being done to yield these advances will significantly impact a number of related fields.

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