Author Archives: Andi

Conducting Elastic Fibers for Artificial Muscles and Electronic Devices

A study at the Dallas based University of Texas shows how scientists have wrapped electrically conducting carbon nanotube sheets around a rubber core to create super elastic fibers. In addition, these fibers conduct electricity and have some special electronic properties as well.

The elasticity of the fibers is phenomenal. They can be more than 14 times longer than their original lengths by stretching and the process is reversible. The fibers regain their initial lengths once the stretching force goes away. While the fibers can extend to 14 times their length, the electrical conductivity steps up by 200 times.

Scientists have conceived of several uses for these fibers. Their high elasticity and conductivity when they stretch could make them ideal for use as minute interconnects in electronic circuits. This could help in upgrading diverse applications like flexible charging cables for mobile devices, robots with longer ranges and trouble-free pacemaker leads.

These fibers are different from conventional fibers in a major aspect. The conductivity of the ordinary fibers falls when they stretch, because of the reduced area of cross section offered to the path of electricity. On the other hand, conductivity of the new fibers increases when stretched.

Dr. Ray Baughman, director of the Nano Tech Institute at Dallas, has authored a paper on the subject. He explains the enhanced elasticity is owing to the buckled structure that develops while the nanotube sheets wrap around the rubber core. Buckles form along the length and circumference of the fibers.

According to Dr. Zunfeng Liu, a research associate in the institute, the two dimensional buckling maintains the alignment of the rubber core and the nanotube. This prevents the resistance of the fibers from rising while they stretch.

Liu reveals that until now, no material has been able to function over so large a range of strain. This feature makes possible the creation of artificial muscles with rotational properties. Dr. Haines, a research associate of the university and a coauthor of the paper said that this aspect of the artificial muscles could be useful for rotating mirrors in optical circuits.

Scientific workers have found several other uses for the nanotube sheaths or elastomers. A particularly valuable device formed from the new material is a fiber capacitor. In this device, a thin coating of rubber covers a core of nanotube fibers. Over this, there is another sheath of nanotube fibers. The inner and outer nanotube layers form the two electrodes, while the rubber core serves as the dielectric.

Nan Jiang is a member of the scientific team working on the project. He demonstrated in the laboratory of the Nanotech Institute the manner of construction of these conductive elastomers in varying sizes, ranging from 150 microns to considerably larger sizes. The width of the rubber core determines the size.

The easy availability and low cost of the rubber cores make it easy for commercialization of the technology. Baughman’s team at the institute has developed a process that aims to convert the carbon nanotubes into large sheets. This could facilitate the fabrication of diverse applications with the elastic conducting fibers.

What is Hyperscale Cooling?

We are more familiar with heat generation in electronic gadgets and methods followed for its removal. Heat sinks are commonly recognized for their function – removing unwanted heat by conduction and convection. Most engineers know how to keep the temperature of the components on their printed circuit boards such as ICs below some maximum allowable value. They are also aware of the heat within the overall enclosure, which may be for a standard rack of boards, a power supply, or a DVR.

Engineers follow several techniques to remove heat from ICs, boards, or enclosures. These often involve the use of one or more heat sinks, heat pipes, heat spreaders, cold plates, and fans. Methods that are more sophisticated use active cooling approaches that include air conditioning or cooling with liquid flowing through embedded pipes. All these are good techniques for handling heat generated with a few kilowatts of power.

However, things change when megawatts of power is involved. Consider for instance, a hyperscale data center that offers a massively scalable compute architecture. Usually made up of small, individual servers called nodes, the hyperscale data center provides computing power, storage, and networking, with the nodes clustered together and managed to form a single entity. Inexpensive, off-the-shelf servers form the nodes. As demand increases, more nodes are attached. Although no formal standard is available as to the minimum power dissipation that can be considered hyperscale, it is safe to admit it is in the range starting at hundreds of kilowatts to megawatts.

According to thermodynamics, energy cannot be created or destroyed. Therefore, the heat removed from the object to be cooled must be delivered to another location that is willing to be heated up. Therefore, when cooling a hyperscale data center, the problem lies in dumping this enormous quantity of heat at a location that can accept it.

BSRIA, an organization involved in testing, instrumentation, research, and consultancy in the construction and building services, has recently conducted a market study. They offer a valuable insight into the cooling options and trends available to hyperscale data centers.

According to the BSRIA report summary, they have represented the feasibility and popularity of techniques versus data-center temperatures in a four-quadrant graph. Among the options shown are reducing dissipation by using modular DC power supplies and variable-speed drives, cooling techniques by using adiabatic evaporation to liquid cooling and allowing a rise in the temperature at the server-inlet. The graph includes growth potential against the investment level necessary for each approach – most popular is the adiabatic/evaporative cooling.

The adiabatic/evaporative process of cooling uses a natural phenomenon to regulate temperature. The cooler uses a large fan that draws in warm air through pads moistened with water, which evaporates. Huge quantities of heat are removed when water evaporates, chilling the air, which is then pushed out to the room. Temperature control is a simple matter of adjusting the airflow of the cooler.

For data centers and other facilities, the adiabatic/evaporative process has saved the industry millions of liters of water. Older cooling towers would pollute the water they used. Adiabatic cooling units also save greater than 40% in electricity consumption.

Raspberry Pi Zero for a Real-Time Sensor Dashboard

Using the Raspberry Pi or RBPi, the single board computer (SBC), and a few applications from Google, you can have a functional dashboard showing real-time parameters from sensors. Google offers its App Engine in the form of a Platform as a Service or PaaS. The advantage is you can deploy and run your own applications using the Google infrastructure without bothering about exclusive ways of setting up hardware, servers, or Operating Systems.

Google also offers the free and powerful Google Charts that you can use as simple charting tools for plotting the data from the sensors into line charts. An HTML5 templates generator such as the Initializr is also useful for generating templates for the dashboard. Initalizr has several useful frontend resources such as Bootstrap and jQuery.

RBPi Zero is the perfect hardware platform to use for this project. This SBC is a full-fledged computer, but smaller than a credit card. It features a single-core CPU running at 1 GHz and 512 MB RAM. Along with a 40-pin GPIO header, the RBPi Zero has USB and a mini HDMI port.

When you connect a few sensors to the GPIO pins, the RBPi Zero sends their data over to the Google App Engine. On the dashboard, you can see the values and the charts updating in real-time as new data arrives from the sensors. Github carries the instructions for building and deploying the project for the RBPi Zero app and the App Engine dashboard.

For this project, Java is the programming language, as both the RBPi Zero and the Google App Engine support it – both use the Pi4J library. However, those who prefer Python can easily change the code, as both RBPi and the Google App Engine support Python as well. As the latest version of Raspbian, the Operating System of the RBPi comes pre-installed with Oracle Java 8, it is easy to deploy and run an executable JAR on the RBPi Zero.

The JAR acts as the go-between with the sensors and the Google App Engine – it reads inputs from the sensors and passes them on to the Google App Engine. You can use the Apache Maven to compile and build the code on the RBPi Zero. Of course, you may also build the code on your laptop or desktop and copy the resulting JAR over to the RBPi Zero.

You can use Cloud Endpoint on the Google App Engine side. This is a powerful service for creating a backend API by using annotations. This includes the client libraries for web and mobiles. It generates a Java based Android client for use with the RBPi Zero application. Google Qauth 2.0 authenticates the API for installed applications.

The RBPi Zero based hardware provides readings from three sensors – voltage generated by a solar cell, temperature from an analog temperature sensor, and illuminance or LUX from a photocell. A 10-bit Analog to Digital converter with SPI interface is necessary to covert the analog signal to a digital format suitable for the RBPi Zero. All the sensors work with a supply of 3.3V, and the RBPi Zero is capable of sourcing this.

Play Chess with the Raspberry Pi

You could be an ardent chess player searching for a worthy opponent. A human opponent may not always be conveniently present, but a computerized player can be relied upon to be available at any time of your choosing. With the Single Board Computer, the Raspberry Pi, or RBPi, you can now play a complicated game of chess, provided you are willing to build a chessboard first.

You will need an Arduino to control the chessboard and an RBPi to run the actual chess engine Stockfish, along with Chessboard, which is the chess rules library. The entire arrangement is completely automated – plug in the different parts, press the green button and you start playing. If there is no automated arm, you must move the pieces manually and the computer signals its move by flashing LEDs. You get 21 levels of play along with the ability to set the personality of the computer – coward or aggressive.

Apart from the personality setting and the 21 levels, Stockfish allows several features. Choose to play with black or with white pieces, and play against the computer or another human. Along with providing hints if stuck, Stockfish recognizes and makes special moves such as Castling, En Passent, and Pawn Promotion. It validates all moves against all rules of chess, signaling errors and allowing re-moves. The chess engine has a maximum rating of GM and an ELO level of 2900.

Although you can use the RBPi alone to control the board and play the chess engine, using an Arduino relieves the RBPi of many functions, speeding up the chess engine running on it. Since the Arduino does not use an Operating System, it is not possible to run Stockfish on it. Although there are chess programs to run on the Arduino, none is as strong as the Stockfish. Moreover, if you are using a computerized arm, the Arduino can take care of operating the motors. The combination of RBPi and Arduino for the chessboard works efficiently.

You can make the board out of wood or plastic according to the materials readily available. A chessboard has 64 squares with alternate black and white colors. To sense the pieces, you need reed switches under each square. These will be wired in the form of a matrix with eight rows and eight columns, with a single reed-switch straddling each junction. By numbering the rows as 1-8 and the columns as A-H, a command E2E4 tells the computer to move the piece from the E2 square to the E4 square.

To let the computer signal its move with LEDs, you will need a second matrix similar to that of the reed switches. Only this time, instead of reed switches, you must place LEDs at the junction points. Using sockets for both the reed switches and the LEDs is advisable as it becomes easy for maintenance. Unlike reed switches, LEDs are polarized, and need to be properly oriented to function. Placing them in sockets helps to re-orient them if they are inserted the wrong way. The Arduino controls both the matrices with data from the RBPi.

Emulating Brain Functions with a Memristor Computer

Chip designs at the atomic level may require emulating the functioning of the human brain, while upholding Moore’s Law. In fact, this might be the only way forward. All forward-looking semiconductor design organizations such as Intel, HP, Samsung, and others know this and this has sparked an exponential interest in the study of memristors.

Among all known electronic components, memristors alone are capable of emulating the brain. It is common knowledge now that a human brain performs far better than the fastest supercomputer, while consuming only about 20 watts of power. Supercomputers cannot emulate, rather only simulate the brain, but they consume thousands of watts and are expensive to the tune of millions of dollars.

At Santa Fe, N.M., Knowm Inc. has expanded its portfolio by adding three different types of memristors. They offer a new high-density die-only option, along with all the raw data manufacturers will need to perform their characterization. Although another organization HP/Hynix is also trying to build commercial memristors, Knowm has beaten them to the market by diversifying its offering of memristors. Knowm is now offering three models with slow, medium, or fast hysteresis, based on the material they are made of – tungsten, tin, or chromium.

Regardless of the basic metal-ion used for its manufacture, all memristors work in the same way. The device consists of two electrodes, with a layer of metal located close to one of them. As a voltage is applied across the electrodes, metal ions move through the device towards the electrode with the lower potential. The device has a layer of amorphous chalcogenide material, which is also its active layer. Metal ions moving through this active layer form a conductive pathway between the electrodes. As the pathways spin through the active material layer, the device resistance drops. When the direction of the applied potential is reversed, the conductive channels dissolve and the device resistance increases.

This characteristic makes the memristor a bipolar device. The memristor also emulates the way neurons in the brain learn. Neurons send pulses through their synapses to strengthen them, equivalent to lowering the resistance, or they do not send pulses, thus causing the synapses to atrophy, equivalent to increasing their resistance.

IBM, together with DARPA or the Defense Advance Research Agency, is developing programs to simulate the process with digital computers. Their software will span the spectrum of accuracy in modeling the way synapses work. However, memristors are the only true emulators of the brain and its functions, so far. Some researchers are going to the extent of erecting scaffoldings for connecting memristor-based emulators to large-scale models. This is creating the need for components such as those Knowm is now offering.

Knowm’s offer is a treasure trove for researchers, being raw data from over 1000 experiments. It helps tremendously, as there is actually no well-defined specification to characterize the memristors properly. That allows researchers to generate their own characterization data, based on the properties of their choice from among the slow, medium, or fast hysteresis types. Knowm offers 16 memristors packaged in a ceramic single dual-in-line package. Their die only option holds 180 memristors.

Can Hardware Thwart Attackers?

At the Gamecon Congress 2015 at Cologne, Germany, Intel announced its 6th Generation of Core processors. Although they did not elaborate, the new chips have vPro on-chip hardware, which is important to the security of business users. Among the new 6th Generation vPro Cores, several of them have new hardware capabilities that include Authenticate and Unite. Intel claims this on-chip hardware to be unhackable, and these can verify the identity of users, allowing them to project their screens onto any WiDi or Wireless Display in the world.

According to Tom Garrison, General Manager of Intel Business Client, the 6th generation vPro Cores will offer workplaces higher productivity, higher security, and higher collaborative experience for business users. As more enterprises now allow users to choose their own devices ranging from Windows to Apple products, Intel is targeting at lowering the price of transforming the workplace in accommodating them. For instance, Intel claims to have dropped their workplace cost per user from $250 to $150 through the transformation.

Intel 6th Gen vPro users now have three-way docking – with their WiDi, WiGig or their business network. They can also use the wired Thunderbolt dock as it has a dual function, charging the laptop and offering 40-Gbit speeds. Intel claims 300 design wins for their 6th generation design WiDi capabilities and about 600 for the WiGig.

According to Intel, with their 6th Gen vPro cores, users will see several improvements, even in the five-year old laptops that several businesses still use. These include a 2.5-fold performance improvement, three times extension of battery life, and 30-times speedier graphics performance. Intel is also offering its mobile users a performance equivalent to Xeon-caliber. However, the most important announcement still remains the authentication hardware from Intel.

According to Garrison, Authentication is a new capability, never before seen. Using Authentication, the information technology department of a business can guarantee the authenticity of any user with two or more factors. That makes break-ins using stolen credentials virtually outdated.

With Authentication, users can select up to four additional factors supported by the unhackable on-chip hardware. This includes PIN, proximity of the phone using Bluetooth, a defined location such as the office, home, or any other, and biometrics such as retina scan or fingerprint.

With Intel Unite hardware, the 6th Gen Core processors allow business users to link their laptop screens wirelessly onto any connected display in the world. They can also control their environment such as dim the lighting and other niceties. Users have to enter a six-digit PIN to connect to any WiDi equipped display, whether in a conference room or anywhere in the world. For business users, this comes complete with Skype. Now, the 6th Generation core users can mirror their laptop display on any big screen-presentation without having to turn to dongles, cords, or wires.

Even in this down market, Intel is claiming 200 business-wins for its 6th Gen vPro Cores, along with 100 vPro design-ins, and over 30 wins with their Intel Ultrabook designs. They have also completed 300 trials of deployment for their WiDi wireless display technology, and more than 600 trials with their WiGig wireless docking design-wins.

What is the MHL Specification?

A present, we are inundated with a plethora of digital devices. For example, we have set-top boxes or STBs, Blu-ray players, AVRs, automobile information systems, monitors, TVs, tablets, smartphones and others making up this large and diverse ecosystem. For getting all these to plug-and-play together is no mean feat and the latest standard connector that manufacturers are adopting for compatibility is the USB Type-C.

The protocol that the USB Type-C will be using for the delivery of audio, video, data and power is the MHL Alt Mode for the superMHL and MHL 1, 2 and 3 specifications. MHL Alt Mode over USB Type-C will allow interconnections of more than 750 million MHL devices. With USB Type-C, you can never plug-in a device in the wrong way – this is a reversible connector.

Backward compatible with USB 2.0 and USB 3.1, both Gen 1 and Gen 2, MHL Alt Mode for USB Type-C features power charging and Immersive audio such as DTS:X, Dolby Digital, Dolby Atmos and more. It allows transmission of 4K data at 60fps over a single lane or 8K data at 60fps over 4 lanes. You can use your existing remote to control existing MHL phones, as there is backward compatibility with existing MHL specifications.

The MHL Consortium has developed and published the MHL Alternate Mode for the superMHL and MHL 1, 2 and 3 specifications. They have established a liaison with the USB-IF and USB 3.0 Promotion Group for obtaining the official SVID and for ensuring the development of the specification confirms to USB Type-C, USB Billboard and USB Power Delivery specifications.

MHL Alt Mode over USB Type-C presents a single, small form factor connector, an ideal for many devices for delivering audio, video, data and power. You can simultaneously charge your smartphone, tablet or notebook when you connect them with larger displays such as car information systems, projectors, monitors and TVs
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You will know your USB Type-C port on your host and device supports MHL if you see the USB-IF logo near the port. Smartphones and tablets with the MHL Alt Mode can easily connect to existing car infotainment systems, projectors, monitors and TVs. With MHL cables and MHL-to-HDMI adapters supporting USB Type-C, you can connect to HDMI Type A devices as well. For this, you will need a simple, thin MHL cable that has an HDMI Type A connector on one end and a USB Type-C connector on the other.

A user can use his existing TV remote to control the device as the MHL Alt Mode supports Remote Control Protocol as well. In contrast, an alternative technology DisplayPort from MPEG-LA does not offer the same compatibility. With the DisplayPort Alt Mode, the user would have to actually go to the connected device and manually control it.

Protocol adapters for the DisplayPort Alt Mode will not work for the MHL Alt Mode and vice-versa. Manufacturers will have to use proper labeling to identify DP Alt Mode or MHL Alt Mode on adapters to avoid consumers from being confused. Proper protocol adapters are necessary for the MHL Alt Mode to support VGA, DVI and HDMI displays.

What is Biometrics?

Many areas are seeing the spread of biometrics. These include military electronics, law enforcement, border protection, industrial and business security, medical devices, consumer electronics and financial transactions. The most important reasons for the rising interest in biometrics comes from the forced emphasis on safety and security because of increasing instances of terrorism, fraud and identity theft.

Biometrics technology is poised for sustained growth. This is also evident from the figures in the recent market research report released by Acuity Market Intelligence. According to this report by Frost and Sullivan, the compounded annual growth rate or CAGR of biometrics technology is expected to be nearly 10.69%, with the annual market revenue reaching $11 billion by 2017.

According to the report, biometric technology earned about $300 million in 2008 in countries such as Africa, the Middle East and in Europe. The report expects this market to reach about $1.5 billion by 2015, representing a CAGR or 25.5%. Similarly, the forecast for North American revenue in biometrics is $9.44 billion.

A major factor in this growth has been Government projects worldwide such as the national identity schemes and e-passports. The biometrics industry continues to lay their emphasis on practical and low-cost standardized approaches for ensuring user friendliness, non-invasiveness and optimal security.

Biometrics employs various modalities for personal identification and verification techniques, with each providing different levels of authenticity. These include signature recognition, voice recognition, vein and palm recognition, hand recognition, facial feature recognition and fingerprinting. A recent addition, the holographic method, has gained popularity. Along with personal data on databases, any of the above modalities can improve authentication and identification greatly.

The public identifies fingerprinting as the most common technique related to biometrics, followed by iris recognition. With improved optical sensing, thermal and capacitive technologies, fingerprinting is improving on several fronts.

For example, NIST or the National Institute of Standards and Technology are promoting a new software technology, the AFEM or Automated Feature Extraction and Matching. This speeds up the manual portion of latent fingerprint identification.

Under normal conditions, a fingerprint examiner has to mark carefully the distinguishing features of a partial or full latent print. This begins with the positions where ridges branch or end. Further identification proceeds when he enters the print into the FBI’s IAFIS or Integrated Automated Fingerprint Identification System.

Trial of the AFEM system on a data set of 835 latent prints and 100,000 fingerprints has shown promising results. Used in real case examinations, the AFEM system demonstrated high accuracy for the latent prints and fingerprints, as high as 80% for half the prototypes.

For each latent print, the software filtered out the distinguishing features and compared them against the 100,000 fingerprints. Against each print, the software was able to provide a list of 50 probable candidates. When specialists compared the fingerprints by hand, they were able to find identities within the top 10.

NIST researchers are working closely with the law-enforcing agencies such as FBI to develop a mobile ID platform. This will allow fingerprinting on the spot, eliminating the need for law-enforcement officials to take people to headquarters for fingerprinting.

How to Safely Grab an Ant

Any child can confirm that ants are not delicate creatures. Their size makes it difficult for us to grab an ant without harming it. Unless you happen to be an Entomologist, wrangling with an ant may not fall into your general activities. However, if for some reason you have to pick or hold something as small or smaller, a micro-tentacle would be the best way to go.

Traditional tweezers are no good when grasping tiny delicate objects such as blood vessels. The process can be painstaking as putting a little too much pressure might crush the object – deciding how much pressure is adequate may also be difficult to gage.

At the Iowa State University, scientists have developed a micro-tentacle or a miniature coiling tentacle, which is just suited for holding tiny objects such as an ant, without causing it any harm. According to the researchers, such micro-scale soft-robots hold a lot of promise as safe handlers for delicate micro-objects. However, to adopt them for wider applications requires easily fabricated micro-actuators of great efficiency.

The micro-actuator for the miniature coiling tentacle developed by the researchers at the Iowa State University is actually a pneumatic actuator based on an elastomeric micro-tube. It is a highly deformable, long and thin micro-tube, based on a new technique called direct peeling. While building the semi-analytical model for shape engineering, scientists use them in combination, amplifying the pneumatically driven bending of the micro-tube into inward spiraling multi-turns.

The result is a micro-tentacle with a grabbing force of nearly 0.78 mN and a final radius as small as 185 µm. That makes it ideally suitable for non-damaging manipulations capable of handling fragile micro-objects. With this spiraling micro-tentacle based grabbing modality, scientists have given the field of soft-robotics several new concepts such as direct peeling, micro-tube shape engineering and the elastomeric micro-tube fabrication technique.

Applications such as vivo biomedical manipulations are increasingly turning to elastomer-based soft-robots for handling delicate objects. Although a lot of headway has been achieved for their micro-scale miniaturization, finding suitable and efficient actuators has remained a difficult task so far. Tentacle actuators composed of polydimethylsiloxane or PDMS elastomers are the answer.

Researchers dip a rod-shaped cylindrical template in a bath containing liquid PDMS. The PDMS clings to the template as researchers pull it out of the bath. They leave the PDMS-coated template in a horizontal position for curing. Most of the gelling elastomer collects on the underside of the template, because gravity pulls it down. That makes the coating on the top much thinner than at the bottom.

When the PDMS sets to a soft and rubbery consistency, it is peeled off the template. That results in a hollow micro-tube, with an uneven wall that is thicker on one side and thinner on the other. Scientists then plug one end of the tube. When they pump air in through the other end, the tube as a whole coils towards on its thinner side and the higher air pressure makes it stiffen. For accentuating the coil formation, scientists add a lump of PDMS to the base of the micro-tube on the outside of the thinner side.

Driving Steppers with the RasPiRobot Board

The Raspberry Pi or RBPi is an inexpensive, tiny single board computer running the Linux operating system. As such, the standalone RBPi is not suitable for running motors, but when combined with an expansion board such as the RasPiRobot Board, you can easily run DC motors as well as Stepper motors off the RBPi. For this, you must use the version 2 of the RasPiRobot or RRBv2 board. Please note you can run only 5V steppers with the RBPi RRBv2 combination, as this board does not support 12V motors.
In practice, the RRBv2 board sits over the RBPi fitting over the latter’s GPIO connector. The stepper motor wires connect to the RRBv2 board, using its L & R screw terminals. To do that, you must first strip the wire ends of their PVC insulation, until about 10 mm of bare copper wire is exposed. Unscrew the terminal sufficiently to allow insertion of the copper part of the wire into the hole. Turn the screw clockwise to let the jaws hold the wire firmly.
One of the advantages of using the RRBv2 board is you can run the stepper motors from a battery pack. The board has a switch-mode power circuit to provide stable power to the motors. Additionally, you can even run your RBPi from this on-board power supply. That makes the entire arrangement completely portable.
When connecting the battery pack to the RRBv2 Board, take care to observe the correct polarity of the flying leads from the battery pack. Some battery packs terminate the wires on a plug. Therefore, you must use a matching female socket adapter that has flying leads. In either case, connect the positive or red lead to the screw terminal marked Vin on the RRBv2 board. Connect the negative or black lead to the screw terminal marked as GND on the RRBv2 board. Powering on/off through a battery pack becomes simpler if there is a built-in switch.
If you have connected your RBPi to the RRBv2 board, throwing the switch to the on position will allow the RBPi to start booting. To run the stepper motor with commands from the RBPi, you will need to download the RRBv2 Python library codes. For this, you will have to connect your RBPi to the Internet.
You can use the Ethernet connection to connect your RBPi to the Internet. Alternately, you may use a suitable Wi-Fi dongle. Once online, use SSH to establish connection to the RBPi from a PC and proceed to download the RRBv2 Python library from here and install it.
To run a stepper motor, you can write some simple Python codes, following the tutorial here. For example, you will have to provide the delay between the steps, the total number of steps you want the stepper motor to move and the direction of rotation – backwards or forwards.
The delay between the steps governs the speed of rotation of the stepper motor. For example, as you make the steps larger, the motor turns more slowly to make the total number of steps.