Bio-Inspired Robot Walks with a Rhythm

Walking robots are not new, as robotic engineers have been fascinated by human movements while walking and have tried to incorporate them into their robots. As a result, we have had several walking robots, starting with WABOT I, the first anthropomorphic robot demonstrated in 1973 by I. Kato and his team at the Waseda University, Japan. Almost everyone remembers ASIMO, a humanoid robot introduced in 2000, as an Advanced Step in Innovative Mobility, designed to be a multi-functional mobile assistant.

Where ASIMO moved as if it were scared of falling, the robotic legs developed by the researchers from the University of Arizona are the first model to be walking in a biologically accurate manner. The robotic legs are based on a bio-inspired combination of a musculoskeletal architecture, complete with a neural architecture and sensory feedback.

The human-like gait of the robotic legs comes from three reasons. First, the musculoskeletal system of the robot is very similar to ours, with artificial tendons and muscles, made from Kevlar straps and servomotors, driving the movements. Second, a variety of sensors on the robot provide a continuous feedback regarding the hip position, limb loading, muscle stretch, foot pressure, and ground contact—all necessary to dynamically adjust its gait. Third, a Central Pattern Generator (CPG) controls the movement of the robot at a relatively high level, mimicking the cluster of nerves that serve the same purpose in a human spinal cord.

When we humans walk, we do so almost without thinking about walking. That is because the nerves within our spinal cord allow us to do so. They collect sensory feedback and use it to adjust the rhythm of our walking style. The CPG works the same way for the robot. Just as a baby learns to walk, the CPG too, creates the simplest walking pattern relying on just two neurons, firing alternately.

Babies exhibit this simple walking pattern when placed on a treadmill, even before they have learnt to walk on their own. Once the robot masters this initial simplistic gait, feedback from other sensors provide additional inputs to form a complex network to allow the robot produce a variety of gaits.

As such, the intention of the research on robotic legs is not to help robots walk better, but rather to understand the neurophysiological process that humans and animals use for walking.

These biped robots have yet to demonstrate how to walk truly autonomously on uneven and various terrains robustly, such as humans do in daily life. However, this class of machines is inspiring the design of efficient simple biped robotic systems that exhibit natural passive gaits, optimal in some energetic sense, and analogous to the comfortable walking gait of humans−the aim being to reduce the consumption of metabolic energy per unit distance to a minimum.

Although researchers have been trying to achieve the above idea by simply compensating for the loss of energy by adding a minimum set of actuators to a passive system when the robot is not descending, they have not yet successfully exploited the idea for operational legged robots.

VNC: Controlling a Raspberry Pi from Anywhere

Sometime you wish you could remotely control your Single Board Computer (SBC), the Raspberry Pi (RBPi). This could be because you have set up your RBPi as a home security system with a camera that you want to monitor remotely, or the RBPi is in control of some appliance that you would like to switch on/off from a remote location. Ordinarily, to access an RBPi from outside your home network, you would need to give it an IP address, and set up your home router accordingly. However, there is another method to bypass all that.

Before you begin, make sure your RBPi has the latest OS installed, and is set up to access your home network. Also, as you will be exposing the RBPi to the Internet, change its default password at the setup process. Once you have done this, you can use VNC Connect to access your SBC from anywhere.

Using VNC, you can easily connect to any computer remotely on the same network. Additionally, VNC Connect allows you to connect to any computer from anywhere using a cloud connection, and this includes the RBPi as well. Once you have set it up, the VNC Viewer app will allow you to access the graphic interface of your RBPi from any other computer or smartphone.

The most recent version of the RBPi operating system, namely PIXEL, comes with VNC Connect already present. Others can install it via the apt-get command. You will need to install both realvnc-vnc-server and realvnc-vnc-viewer. Once you have done that, run the raspi-config and set VNC as enabled. This will allow you to set up VNC Connect.

Use a browser to go to the sign-up page of RealVNC Raspberry Pi. Enter your email address in the sign up box. The on-screen instructions will now guide you to complete setting up your account with a password.

On the screen of your RBPi, you should see a VNC icon, which you can click to open. Now, click on the Status Menu and select Licensing. Here, you can enter your email address and its password you created on the sign-up page. On the next prompt, select Direct and Cloud Connectivity, to make your RBPi accessible online.

Now go to the computer or smartphone from which you would like to control your RBPi, and download the VNC Viewer application therein. Open the application, and enter your email address and its password you created on the sign-up page.

This should make your RBPi pop-up automatically as an option. You can use to open up the connection. It will prompt you for the username and password of your RBPi. By default, this is pi as username and raspberry as password, unless you have changed the password as instructed earlier. It takes only a few seconds to connect to your RBPi.

Now, as long as your RBPi is connected to the Internet, you can log into and access its graphic desktop from anywhere. That means you have complete control of any software on the RBPi, check on the status of any project it is running, or even play the games stored on your private server.

Raspberry Pi Zero Goes Wireless

The Raspberry Pi product line has added a new member, the Raspberry Pi Zero W (RBPiZW), an updated version of the RBPi Zero, with the added advantages on on-board Wi-Fi and Bluetooth capability.

Although the new RBPiZW lacks the Ethernet and full-sized USB-A ports, it is only a fraction of the size of its flagship brethren the RBPi, and less expensive as well. Almost identical to the RBPi Zero, the RBPiZW is twice as expensive, and boasts of a wireless chip supporting the 802.11 b/g/n Wi-Fi for 2.4 GHz only, and Bluetooth 4.0.

Both the RBPiZW and RBPi Zero use the same BCM2835 that powered the original RBPi. However, the single-core chip is now clocked at a higher speed of 1 GHz, as against 700 MHz earlier. On the RBPiZW is a Cypress wireless chip, the same the RBPI3 also uses. Although the Raspberry Pi Foundation has claimed the maximum wireless speed of the chip as 150 Mbps, in reality it generally hits about 20 to 40 Mbps.

Apart from the addition of the Bluetooth and Wi-Fi, there has been no change from the RBPi Zero to the RBPiZW. The designers added the Bluetooth and wireless LAN chipsets to the board, and included a PCB antenna layout licensed from ProAnt, Sweden.

The RBPiZW contains 512 MB RAM, a HAT-compatible 40-pin header, a CSI camera connector, a Micro-USB for power, Mini-HDMI port, a USB port for OTG, and headers for composite video and reset.

Although the new RBPiZW is a trifle heavier than its predecessor the RBPi Zero is, their dimensions are identical at 2.6×1.2×0.2 inches. You can also get a new case with the RBPiZW, with three interchangeable lids. The first lid is solid, the second has an opening in it for the GPIO pins, and the third has an opening for the camera module.

As the RBPiZW (and the RBPi Zero) come without the GPIO pins installed, they are able to maintain their slim profile, despite their full-sized GPIO headers. The user can solder the GPIO pins if the project demands, but the small size of the Zero boards are an advantage when using them to build a small robot or any other small system.

Even though the price is slightly higher, the RBPiZW remains incredibly cheap and is far more useful out of the box. Measurements of the performance of the tiny SBC confirm this. However, considering general performance when comparing with the RBPi3, such as during web browsing, it may be a frustrating experience. The RBPiWZ will have long pauses as the data loads and graphics renders in the Epiphany browser.

That means the RBPiZW is geared more towards hardware and software hackers, rather than those trying for a desktop experience. Those who want a replacement for their desktop computers would do well to use the RBPi3 instead.

Another factor weighing in for the RBPiZW is its low power consumption. Considering this board is meant for small systems and tiny robots, its low power consumption is a very big advantage when powering projects with batteries. Of course, the Wi-Fi support and network performance will affect its power consumption pattern.

SALTO the Agile Jumping Robot

In the Biomimetic Millisystems Lab at UC Berkeley, Duncan Haldane is responsible for numerous bite-sized bio-inspired robots—robots with hairs, robots with tails, robots with wings, and running robots. Haldane and the other members of the lab look at the most talented and capable animals for inspiration for their robotic designs.

The African Galago or Bushbaby is one such animal. It is a fluffy, cute, talented, and capable little jumping animal weighing only a few kilos. However, this little creature can jump over and clear bushes nearly two meters tall in a single bound. Biologists have discovered that Galagos’ legs are specially structured to amplify the power of their tendons and muscles. Haldane and his team accordingly made Salto, a legged robot weighing only a hundred grams, endowing it with agility and the most impressive jumping skills. Salto features in a paper the new journal Science Robotics.

Jumping is not only about how high one can jump, how frequently you can jump also matters. Haldane and his team have coined the term agility to refer to how far upwards one can go while jumping repeatedly. Technically, they define it as the maximum average vertical velocity achieved while performing repeated jumps. For a Galago, it can jump 1.7 m in height repeatedly every 0.78 s—an agility of 2.2 m/s.

Therefore, to be called agile, the jumper not only has to jump high, he also has to be able to jump frequently. For instance, although EPFL’s Jumper can jump to impressive heights of 1.3 m, it can only do so every four seconds. That means its agility is a measly 0.325 m/s. On the other hand, Minitaur can jump up only to 0.48 m, but it does so every 0.43 s, which gives it a much better agility of 1.1 m/s, despite its lower jumping ability.

That means improving agility involves jumping either higher, or more frequently, or both. Galagos are agile, because of not only their ability to jump high, but also their ability to do so repeatedly. Most jumping robots have low agility, because, they need to spend time winding a spring for storing up enough energy to jump again, and this reduces their jump frequency. The researchers at Berkeley wanted a robot with an agility matching that of the Galagos. With Salto, they have come close, as Salto can jump 1 m every 0.58 seconds, earning an agility of 1.7 m/s.

Just as with many jumping robots, Salto also uses an elastic element, such as a spring, for the starting point. For Salto, the spring, actually a piece of twistable rubber is placed in series between a motor and the environment, making a Series Elastic Actuator (SEA). Apart from protecting the motor, SEAs also allow for force control and power modulation, while allowing the robot to recover some energy passively.

Such springs are available to the Galagos in the form of their tendons and muscles. However, the leg of the Galagos is in such a form that allows it to output nearly 15 times more force than its muscles can by themselves. Haldane has used this same design for Salto as well.

Six-Legged Robot is faster than Insects

Evolution follows very intelligent designs, filtering out the failures by trial and error. However, evolution in nature takes place over billions of years, but that span of time may not be available to designers of robots. Usually, robotics design, inspired by biology, is about the designer figuring out the clever tricks that evolution has perfected and applying them to the robot for beating nature at her own game.

For instance, studies have shown that most six-legged insects move with a tripedal gait, meaning they move at least three legs at a time. On the other hand, EPFL researchers from Lausanne, Switzerland, have reported in Nature Communications that a bipedal gait for a hexapod is more efficient and a faster way of moving—using two active legs at once.

When moving, especially when moving fast, animals with legs tend to minimize the time their legs remain in contact with the ground. Therefore, fast moving mammals prioritize flight phases, in which their motion seems more like a sequence of jumps rather than fast walking. However, for hexapedal insects, whether they are moving slowly or fast, movement consists of keeping at least three legs in contact with the ground at all times.

Mathematically, the tripedal gait is less efficient than a gait involving two legs. This is simple to calculate, as a hexapod using three legs at a time gets two power strokes per gait cycle, whereas, if it used two legs at a time, it would instead get three. The EPFL researchers tested this theory on hexapedal robots. They conclusively proved that by using two legs at once instead of three, hexapedal robots could move 25% faster. Therefore, rather than use the natural tripedal gait of insects, a hexapedal walking robot, with a bipedal gait, could be more dynamic, although statically not so stable. That brought the investigators to an interesting question: why are insects using a slower gait, when they could be moving faster?

The researchers found that insects also needed to move on places that are not always upright and horizontal, such as walls and ceilings. Walking on walls and ceilings requires feet that stick or grab to surfaces—most flying insects have this capability. They concluded that for walking while clinging to surfaces, it is best to follow a tripedal gait, but when running on the ground, a bipedal gait is faster.

The researchers tested their theory further by negating the adhesive property of insects’ feet by giving flies some polymer boots. The flies responded by moving on to a bipedal gait from a tripedal one. Even when placed on a very slippery surface, their behavior did not change, suggesting the tripedal gait was due to the structure causing the adhesion in the legs, or the sensory feedback the legs generated. This experiment proved conclusively that even when adhesion was unnecessary, insects could not move to a bipedal gait, as having sticky feet, they needed the leverage of three legs to unstick the other three.

Such biorobotics helps us in two ways. On one hand, it explains why nature works the way it does, and on the other, it shows how we can make faster and better robots.

Connect with a New Type of Li-Fi

Many of us are stuck with slow Wi-Fi, and eagerly waiting for light-based communications to be commercialized, as Li-Fi promises to be more than 100 times faster than the Wi-Fi connections we use today.

As advertised so far, most Li-Fi systems depend on the LED bulb to transmit data using visible light. However, this implies limitations on the technology being applied to systems working outside the lab. Therefore, researchers are now using a different type of Li-Fi using infrared light instead. In early testing, this new technology has already crossed speeds of 40 gigabits per second.

According to the Li-Fi technology, a communication system first invented in 2011, data is transmitted via high-speed flickering of the LED light. The flickering is fast enough to be imperceptible to the human eye. Although lab-based speeds of Li-Fi have reached 224 gbps, real-world testing reached only 1 gbps. As this is still higher than the Wi-Fi speeds achievable today, people were excited about getting Li-Fi in their homes and offices—after all, you need only an LED bulb. However, there are certain limitations with this scheme.

LED based Li-Fi presumes the bulb is always turned on for the technology to work—it will not work in the dark. Therefore, you cannot browse while in bed in the dark. Moreover, as in regular Wi-Fi, there is only one LED bulb to distribute the signal to different devices, implying the system will slow down as more devices connect to the LED bulb.

Joanne Oh, a PhD student from the Eindhoven University of Technology in the Netherlands, wants to fix these issues with the Li-Fi concept. The researcher proposes to use infrared light instead of the visible light from an LED bulb.

Using infrared light for communication is not new, but has not been very popular or commercialized because of the need for energy-intensive movable mirrors required to beam the infrared light. On the other hand, Oh proposes a simple passive antenna that uses no moving parts to send and receive data.
Rob Lefebvre, from Engadget, explains the new concept as requiring very little power, since there are no moving parts. According to Rob, the new concept may not be only marginally speedier than the current Wi-Fi setups, while providing interference-free connections, as envisaged.

For instance, experiments using the system in the Eindhoven University have already reached download speeds of over 42 gbps over distances of 2.5 meters. Compare this with the average connection speed most people see from their Wi-Fi, approximately 17.5 mbps, and the maximum the best Wi-Fi systems can deliver, around 300 mbps. These figures are around 2000 times and 100 times slower respectively.

The new Li-Fi system feeds rays of infrared light through an optical fiber to several light antennae mounted on the ceiling, which beam the wireless data downwards through gratings. This radiates the light rays in different direction depending on their wavelengths and angles. Therefore, no power or maintenance is necessary.

As each device connecting to the system gets its own ray of light to transfer data at a slightly different wavelength, the connection does not slow down, no matter how many computers or smartphones are connected to it simultaneously.

How Do Wind Turbines Work?

Wind turbines generate electricity from moving winds. You can see them in large numbers on wind farms both onshore and offshore. The blowing wind turns their blades, and rotates the shaft on which the blades are mounted. The shaft in turn, operates an electric generator and the resulting electric output is sometimes stored in a battery. A swarm of wind turbines can generate a substantial amount of energy. Wind turbines are often called a renewable source of energy, as they generate power from natural renewable sources, and do not consume fossil fuel, a source that cannot be replenished.

Inside the wind turbine, there are several control systems at work. These include its ability to turn the face of the turbine into the wind, called yawing, and its ability to control the angle of its blades, called pitch. Yawing and pitch extract the maximum amount of power from the blades rotating in the wind and require motors and controls. However, the yawing of a wind tower may actually twist the cables inside. The wind turbine usually has electronic intelligence built inside to untwist the cables.

The wind actually propels the blades, which are designed using the laws of physics and vectors to extract the maximum from the wind driving them. Speed analysis shows the maximum efficiency the wind turbine can achieve is about 59%. The laws of physics, especially Betz’s limit prevents the wind turbine from achieving efficiencies any higher.

As mentioned earlier, the main parts of a wind turbine are the blades mounted on a shaft. As the blades turn with the wind, the shaft rotates and spins a generator to make electricity. Most designs of wind turbines use electronic controls to generate the 60 Hz AC sine wave, although there are wind turbines that generate DC as well.

Typically, a doubly-fed induction generator is used to generate three-phase power. As this requires capacitors and a DC link, workers need to monitor the systems periodically to prevent failure of capacitors. Most of the control is similar to that used for controlling bidirectional motors, using IGBTs, and rectifier diodes in a full bridge arrangement. These components are rather large, considering the voltage generated is nearly 690 volts, and the power is in megawatts. Transformers step up the voltage from the generator to the grid power line, and there is built-in protection to limit the spikes as the speed of the wind increases.

The rotation speeds for wind turbine blades are 5-20 rpm, while a generator needs to rotate at speeds between 750 and 3600 rpm to generate power. Therefore, a gearbox in between translates the speeds. When maintenance time comes around, a combination of yawing and proper pitch is used to stop the rotation. Workers then insert pins into the shaft, locking the blades to prevent them from spinning.

Workers servicing and maintaining the blades have to dangle from ropes hundreds of feet above the ground in the air. Other parts, being within the tower, can be maintained more easily. In general, the maintenance and servicing for a wind turbine is similar to that required by any other turbine in a power generating station.

Lichee Pi – Another Contender for the Raspberry Pi

If you are looking for an alternative to the ubiquitous Raspberry Pi (RBPi), check out the Lichee Pi Zero. The basic board costs only $6.00 and another two dollars will get you the Wi-Fi version. Powered by the Allwinner V35 CPU, it is even smaller than the RBPi Zero, and works with the latest Linux kernel 4.10. The crowdfunding campaign offers a huge range of accessories.

The ARM-based processor on the Lichee Pi Zero, the Allwinner V35, is an ARM Cortex-A7 CPU. It has a maximum speed of 1.2 GHz, has 512 MB DDR2 RAM integrated in it, and you can boot it from the TF card or the on-board SPI Flash. The Lichee Pi Zero runs its processor at 1.0 GHz, and the board consumes less than 100 mA, so you will not need any cooling arrangements such as fans or heat sinks.

The Lichee Pi Zero is well designed for external connections, as it has plenty of pins available for the task. For instance, you can use its 30 pins to easily plug it into a breadboard, or solder all the 60 pins on it. You can also connect its TF Wi-Fi Card.

On the top side of the Lichee Pi Zero board, one can see the MPU, RGB LED, LCD backlight circuit, TF Slot, and the microUSB ports for OTG and Power. On the bottom side is the Touch Screen Controller, SPI Flash, DCDC Power, and the FPC40 RGB Connector. You can connect the Lichee Pi Zero directly to the LCD, no video cable is necessary. Therefore, if you add to the Lichee Pi Zero an LCD, a Li-Polymer battery, a wireless keyboard, and a simple holder, you can make a mini Laptop.

Like most MCU, the Lichee Pi Zero can connect to several low-speed interfaces, such as GPIO, UART, PWM, ADC, I2C, SPI, and more. Moreover, it can run other high-speed peripherals such as RGB LCD, EPHY, MIPI CSI, OTG USB, and more. The Lichee Pi Zero has an integrated codec that allows direct connection to a headphone or microphone.

The Dock for the Lichee Pi Zero is quite powerful. It offers support for a 5 MP MIPI camera, battery manager, 4 ADC-keys, Ethernet RJ45 Connector, audio jack, microphone, an additional TF slot, and multiple pins for PWM, I2C, SPI, and UART.

The Dock also has a PA slot, through which you can plug in PA modules. Several speakers are supported, including bone conduction speakers, 1-W, and 3-W speakers. The Dock will also support small sized LCD and OLD displays, such as the 2.4-inch 240×320 TFT display, or the 0.96-inch 128×64 OLED display. You can also connect a joystick and keyboard for the setup to work as a miniGameBoy.

On the software side, the Lichee Pi Zero uses the newest Linux 4.10 kernel, and is able to run the Debian Jessie with pixel. The buildroot root file system allows you to put the kernel and the root file system of the Lichee Pi Zero into 8 MB of SPI Flash. The ZeroW Dock mini laptop suit allows you to build your own laptop, with battery manager and Ethernet support.

Rechargeable Battery Packs Benefit From Integrated Battery Pack Monitor

Increasingly, electronic devices are depending on more than one battery unit for deriving power—driving motors require a higher voltage than does the control system. This includes energy storage systems, toys, scooters, e-bikes, handheld power tools, lawn equipment, and vacuum cleaners. So far, battery monitors could only monitor the entire battery pack and not the individual batteries making up the pack. Now, Intersil has developed a battery pack monitor with a difference. Not only can it monitor 3-to-8 cells simultaneously and individually within a pack, it can cater to different battery chemistries as well.

The battery pack monitor from Intersil, the highly integrated ISL94202, enables designers to restrict their design to only two terminals, while accurately monitoring, protecting, and balancing each cell of a rechargeable battery pack, thus ensuring their safe operation and charging.

Acting as a stand-alone protection system for batteries, the ISL94202 has an internal state machine sporting five pre-programmed modes. Apart from accurately balancing and controlling each cell in the battery pack, these modes also protect the entire pack from catastrophic events such as cell voltage over-discharge/ overcharge, short circuit conditions, and hardware faults. Additionally, the ISL94202 conforms to the pack safety requirements of IEC62133, UL2271/72, and UL2054 standards.

Using the ISL94202 does not require an external microcontroller. Designers can directly program the battery pack monitor, which Intersil claims can control the smallest and least expensive battery packs available in the industry. However, the ISL94202 has an I2C serial communication bus, through which it can transfer data such as the state of health, state of charge, and fuel gauge measurements related to the cells to an external microcontroller. The device has a high-side current measurement feature that enables precise fuel gauge status monitoring.

It is easy to interface the ISL94202 to tools or electric motor equipment, as the battery pack monitor integrates high-side FET drive circuitry for charging and discharging—keeping all electronics at ground level reference. The device also has external passive cell-balancing switch controls, which ensure proper cell energy matching, while protecting the cells individually from chronic undercharging. Manufacturing is greatly simplified as the ISL94202 has the capability to withstand hot plug events such as those happening during factory assembly of battery packs.

According to Philip Chesley, a senior vice president with Precision Products at Intersil, customers can expect all the necessary front-end battery features from the ISL94202, against catastrophic pack failures. The innovative high-side FET control can monitor current and cell measurement while delivering a small footprint solution for efficient battery pack designs.

ISL94202 has a temperature sensor interface, power FET control, current sense monitor, and automatic cell balance using a 14-bit ADC, all without needing recourse to an external microcontroller. It can handle cell voltage level shifts of up to 4.8 V per cell, while monitoring for different battery chemistries such as Li-ion FePO4, Li-ion Mn2O4, and Li-ion CoO2.

For cell balancing, the ISL94202 can use external FETs being driven by the internal state machine of the device, or an external microcontroller. Additionally, the ISL94202 covers the operational industrial temperature range of -40°C to +85°C, measures 6X6 mm, and comes in a 48-lead QFN package.

Treat Yourself to a Raspberry Pi Zero W

The launch of the Raspberry Pi Zero W (RBPiZW) by the Raspberry Pi Foundation recently has added two features many fans of the RBPi have been requesting for a long time. The two features, built-in Wi-Fi and Bluetooth, added to the wonderful RBPi Zero have improved the functionality of the tiny single board computer.

After all, the RBPiZW is only a variant of the RBPi Zero, and therefore, does not merit a full length, in depth review. However, we will focus on the new features the RBPiZW brings to the users.

Keeping with the tradition of the RBPi family of SBC, there is no case or anything to enable the user to treat the RBPiZW as a commercial product. Just like the other RBPi products before it, the RBPiZW is a complete single board computer, bare bones, versatile, and cheap. The Foundation has created the board this way so all hobbyists and professionals can use it with equal ease to make anything they want.

As with the original RBPi Zero, the RBPiZW also has its System-on-a-Chip (SoC) near the middle of the board, while the bottom of the board has the various mini and micro ports. For instance, rather than a full sized HDMI port, the board has a mini-HDMI port for the display to be connected. At the bottom, you will also find two micro-USB ports. One is used for supplying power to the board, and the other to carry data in and out. Therefore, if you wish to connect peripherals such as a mouse or a keyboard, you will need to use a micro-USB B male to USB A female adapter.

On the left side of the board, you will find the micro-SD slot. As with the other RBPi boards of the family, the RBPiZW also does not have built-in flash memory. Therefore, for the Operating System and data storage, you must use a micro-SD card else, you will not be able to boot the tiny computer.

Although there is an Ethernet port on the RBPiZW to connect to the Internet via an Ethernet cable, the presence of the on-board Wi-Fi precludes the use of a USB Wi-Fi dongle. That means even if you do not have a ready Ethernet cable, the RBPiZW will not face any difficulty in surfing the net.

To enable to RBPiZW to start running, you will need to supply it power from its power supply through the micro-USB cable. You must also have a micro-SD card of at least 8 GB capacity and the relevant OS stored on it. If you are going to connect a monitor to the RBPiZW, you will also need a mini-HDMI to HDMI adapter, and an HDMI cable. As you have used up one USB port for power, there is only one more micro-USB port available. Therefore, to connect a keyboard and mouse, you will additionally need a small USB hub. Of course, if you have a Bluetooth mouse and keyboard, the single micro-USB port is enough, and you can dispense with the USB hub altogether. For headless applications, you can also discard the monitor, and the HDMI connectors/cables.