Servo - August 2016

capable of sophisticated human interactions, and can upload lessons it has learned to and from the cloud to interact with other Pepper robots.

The robot’s design combines voice recognition with a computer capable of understanding complex human responses, and it can be used for babysitting or acting as a nurse or as a personal companion for elderly folks. (This is an application that I have long been interested in.) When the robot’s production is geared up for mass distribution, the robot will be manufactured by Taiwan-based Hon Hai Precision Industry.

Journalists from Nikkei Technology and other news agencies have noted that Pepper is quite complex, with 20 motors driving the articulated arms and hands, head motions, dual waist motions, and the base tri-ball omni-directional drive system shown in

Figure 3.

Early reviewers with robotics knowledge feel that the robot could be made less complex for mass production, but all seem to agree that the design made sense. It has an Intel Atom microprocessor mounted in the head giving it the power of a high-end tablet, and uses its sensors and four microphones plus ASUSTeK 3-D cameras for advanced speech recognition, as well as human facial identification.

Fans are used to cool the processor. It has a 10 pound battery in the lower base which gives Pepper a 12 hour operating time. The robot has an overall weight of about 64 pounds. The company has plans in place to improve Pepper’s internal parts layout and reduce production costs.

Quality Parts for Mobile Personal Robots

I used the Pepper robot as a ‘base’ example of a great mobile robot design, where the company is constantly refining many aspects to improve the overall design. I am going to concentrate on mobile personal robots for the majority of this article as those are of the greatest interest to many readers. Mobile robots of today take on many forms. The majority are of the three- or four-wheel variety that travel on floors or outside of buildings. Other popular designs include bipedal walkers that attempt to move like us.

Two-wheeled accelerometer-balanced robots have also been popular as the best way to simulate the human form. Leaving the ground are AAVs (autonomous aerial vehicles), or as they are called these days, drones. Autonomous underwater vehicles (AUVs) can be totally autonomous, or — as the acronym applies — ROVs (tethered remotely operated vehicles). These have been used by underwater researchers for years.

Buy the Best Batteries for Your Robot

Let’s discuss some of the more critical parts for a robot project. With the mobile aspect in mind, most of us builders will turn to battery technology to power our machines. Batteries and their power density seem to be the biggest limitation in designing the ultimate robot — especially bipedal humanoid robots. In days past, the majority of robots that I built over the years and those of other home and university experimenters, the power source of choice was the lead-acid battery.

In the beginning, the only lead-acid batteries available to experimenters were those with liquid sulfuric acid electrolyte designed for yard tractors, motorcycles, and cars. It doesn’t take much imagination to see how such batteries can be dangerous — both to humans and the robots in which they were installed.

I saw several remotely controlled ‘promotional’ robots over the years that had steel aluminum structure and control electronics ruined by a damaged or overturned liquid acid battery. I even saw an operator’s van that had the steel floorboard eaten through by a battery that overturned in his robot while stored in the van. Fortunately, gelled electrolyte batteries became readily available in the ‘80s and they were not so ‘evil’ in devouring robot innards. These are still popular today as they are available in higher current capacities. Nickel-cadmium or ‘NiCad’ batteries are another choice that has been around for a while. These do have good high current capacity for driving motors, and are frequently still used in lower-end power tools such as drill motors and cordless yard and garden tools. Another style of battery that has earned a reputation for toasting a few robots is the lithium-polymer battery, made popular for its use in laptop computers, drones, and cell phones. The popularity is derived from not necessarily the large power density, but for the flat cell design that allows them to fit into tiny spaces. There have been a few cars that were set on fire from a laptop that spontaneously Post comments on this article at www.servomagazine.com/index.php/magazine/article/ August2016_Locating-Selecting-Parts-for-Robots.