Specials!

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The LSM303DLM combines a digital 3-axis accelerometer and 3-axis magnetometer into a single package that is ideal for making a tilt-compensated compass. The six independent readings, whose sensitivities can be set in the ranges of ±2 to ±8 g and ±1.3 to ±8.1 gauss, are available through an I²C interface. The carrier board operates from 2.6 to 5.5 V and has a 0.1″ pin spacing.

Clearance: This board is being replaced by the newer LSM303DLHC carrier (which is pin-compatible) and LSM303D carrier.

This board is a simple carrier of Allegro’s ±12.5A ACS711 Hall effect-based linear current sensor with overcurrent fault output, which offers a low-resistance (~1.2 mΩ) current path and electrical isolation up to 100 V. This version accepts a bidirectional current input with a magnitude up to 12.5 A and outputs a proportional analog voltage centered at Vcc/2 with a typical error of ±5%. It operates from 3 V to 5.5 V, so it can interface directly to both 3.3 V and 5 V systems.

This board is a simple carrier of Allegro’s ±25A ACS711 Hall effect-based linear current sensor with overcurrent fault output, which offers a low-resistance (~1.2 mΩ) current path and electrical isolation up to 100 V. This version accepts a bidirectional current input with a magnitude up to 25 A and outputs a proportional analog voltage centered at Vcc/2 with a typical error of ±5%. It operates from 3 V to 5.5 V, so it can interface directly to both 3.3 V and 5 V systems.

This gyroscope board is a basic carrier/breakout board for the ST LPY550AL dual-axis gyro, which measures the angular rates of rotation about the pitch (x) and yaw (z) axes. Two separate analog voltage outputs for each axis provide angular velocity ranges of ±500°/s and ±2000°/s. This board has a 3.3V regulator for easy integration with 5 V parts, includes a low-pass filter on each output for noise reduction, and is smaller than competing products, all at a lower price.

Clearance: This board is being replaced by the L3GD20H 3-axis gyro carrier.

Clearance: This is the original version of our digital-output RC switch, which converts hobby radio control pulses to digital on/off signals for use in RC switch and simple RC adapter applications. One output indicates the presence of a valid RC signal (10-100 Hz pulse rate, 0.5-2.5 ms pulse width), and the other output indicates whether the pulse width is above or below the 1.6 ms threshold (with ±0.1 ms hysteresis).

Note: A newer version of this product is available, and this part is now on clearance.

The LSM303DLHC combines a digital 3-axis accelerometer and 3-axis magnetometer into a single package that is ideal for making a tilt-compensated compass. The six independent readings, whose sensitivities can be set in the ranges of ±2 to ±16 g and ±1.3 to ±8.1 gauss, are available through an I²C interface. The carrier board operates from 2.5 to 5.5 V and has a 0.1″ pin spacing.

Clearance: This board is being replaced by the newer LSM303D carrier.

This printed circuit board is designed for building your own circuits based on Microchip Technology’s line of 8-pin PIC microcontrollers. The board holds a PIC and the basic circuitry necessary to run it. The rest of the board is available for your custom circuits.

With possible gear ratios of 39.6:1, 47.6:1, 61.7:1, and 74:1, the Tamiya 72007 4-Speed High-Power Gearbox is well-suited for most applications that require a balance of speed and torque.

The primary feature of this gearbox is a worm gear, which locks the output shaft when the motor is not turning. Its high gear ratios of 84:1, 216:1, 555.4:1, and 1428.2:1 make this gearbox appropriate for small walking robots, lifting mechanisms, and other applications where high torque is desired.

This round printed circuit board is a general-purpose prototyping board for developing your own custom electronics designs. Slightly larger than a CD, this PCB also fits our round robot chassis perfectly. With 1,780 holes, the board has ample space for most projects.

Tamiya’s 8-speed mini motor gearbox features a more compact 030-form-factor brushed DC motor driving a single gear train that can be assembled to have one of eight gear ratios: 7.5:1, 9.5:1, 15.7:1, 19.9:1, 32.9:1, 41.8:1, 79.1:1, or 87.8:1.

Tamiya’s 12-speed multi-ratio mini motor gearbox features a more compact 030-form-factor brushed DC motor driving a single gear train that can be assembled to have one of twelve gear ratios: 4.6:1, 5.1:1, 9.7:1, 10.8:1, 20.4:1, 22.6:1, 42.8:1, 47.5:1, 89.9:1, 99.8:1, 188.7:1, or 209.7:1.

Tamiya’s 4-speed low-speed mini motor gearbox features a more compact 030-form-factor brushed DC motor driving a single gear train that can be assembled to have one of four gear ratios: 71.4:1, 149.9:1, 314.9:1, or 661.2:1. The gear train includes a self-locking worm gear.

This 12 V linear actuator can be used in a variety of heavy-duty applications. The motor has 20:1 reduction gearbox that gives the actuator a dynamic load rating of 110 lbs (50 kg) and a maximum speed of 0.5 in/s (1.3 cm/s), and it is rated to withstand up to 500 lbs when not moving. Limit switches at each end make the actuator easy to control over its full range of motion, and the worm drive ensures that the shaft will hold its position even when unpowered. This version has a 2-inch stroke and a built-in potentiometer for position feedback.

This 12 V linear actuator can be used in a variety of heavy-duty applications. The motor has 20:1 reduction gearbox that gives the actuator a dynamic load rating of 110 lbs (50 kg) and a maximum speed of 0.5 in/s (1.3 cm/s), and it is rated to withstand up to 500 lbs when not moving. Limit switches at each end make the actuator easy to control over its full range of motion, and the worm drive ensures that the shaft will hold its position even when unpowered. This version has a 4-inch stroke and a built-in potentiometer for position feedback.

This 12 V linear actuator can be used in a variety of heavy-duty applications. The motor has 20:1 reduction gearbox that gives the actuator a dynamic load rating of 110 lbs (50 kg) and a maximum speed of 0.5 in/s (1.3 cm/s), and it is rated to withstand up to 500 lbs when not moving. Limit switches at each end make the actuator easy to control over its full range of motion, and the worm drive ensures that the shaft will hold its position even when unpowered. This version has a 6-inch stroke and a built-in potentiometer for position feedback.

This 12 V linear actuator can be used in a variety of heavy-duty applications. The motor has 20:1 reduction gearbox that gives the actuator a dynamic load rating of 110 lbs (50 kg) and a maximum speed of 0.5 in/s (1.3 cm/s), and it is rated to withstand up to 500 lbs when not moving. Limit switches at each end make the actuator easy to control over its full range of motion, and the worm drive ensures that the shaft will hold its position even when unpowered. This version has an 8-inch stroke and a built-in potentiometer for position feedback.

This 12 V linear actuator can be used in a variety of heavy-duty applications. The motor has 20:1 reduction gearbox that gives the actuator a dynamic load rating of 110 lbs (50 kg) and a maximum speed of 0.5 in/s (1.3 cm/s), and it is rated to withstand up to 500 lbs when not moving. Limit switches at each end make the actuator easy to control over its full range of motion, and the worm drive ensures that the shaft will hold its position even when unpowered. This version has a 10-inch stroke and a built-in potentiometer for position feedback.

This 12 V linear actuator can be used in a variety of heavy-duty applications. The motor has 20:1 reduction gearbox that gives the actuator a dynamic load rating of 110 lbs (50 kg) and a maximum speed of 0.5 in/s (1.3 cm/s), and it is rated to withstand up to 500 lbs when not moving. Limit switches at each end make the actuator easy to control over its full range of motion, and the worm drive ensures that the shaft will hold its position even when unpowered. This version has a 12-inch stroke and a built-in potentiometer for position feedback.

This 12 V linear actuator can be used in a variety of heavy-duty applications. The motor has 5:1 reduction gearbox that gives the actuator a dynamic load rating of 34 lbs (15 kg) and a maximum speed of 1.7 in/s (4.3 cm/s), and it is rated to withstand up to 450 lbs when not moving. Limit switches at each end make the actuator easy to control over its full range of motion, and the worm drive ensures that the shaft will hold its position even when unpowered. This version has a 4-inch stroke and a built-in potentiometer for position feedback.

This 12 V linear actuator can be used in a variety of heavy-duty applications. The motor has 5:1 reduction gearbox that gives the actuator a dynamic load rating of 34 lbs (15 kg) and a maximum speed of 1.7 in/s (4.3 cm/s), and it is rated to withstand up to 450 lbs when not moving. Limit switches at each end make the actuator easy to control over its full range of motion, and the worm drive ensures that the shaft will hold its position even when unpowered. This version has a 12-inch stroke and a built-in potentiometer for position feedback.

Tamiya’s double gearbox packs two independent gear trains into a compact and affordable package that is great for small mobile robots. Each side can be assembled to have one of four gear ratios: 12.7:1, 38:1, 115:1, or 344:1.

Tamiya’s twin-motor gearbox consists of two independent brushed DC motors and gearboxes in one compact housing, making it perfect for small robots. You can assemble the gearboxes to have a 58:1 or a 204:1 gear ratio.

This gearbox features a low-current brushed DC motor, which is great for projects where you want to keep your power consumption to a minimum. Its single gear train can be assembled to have one of three gear ratios: 12.7:1, 38.2:1, or 114.7:1.

This sensor is a carrier/breakout board for the ST L3GD20 three-axis gyroscope, which measures the angular rates of rotation about the roll (X), pitch (Y), and yaw (Z) axes. Angular velocity measurements with a configurable range of ±250°/s, ±500°/s, or ±2000°/s can be read through a digital I²C or SPI interface. The board has a 3.3 V linear regulator and integrated level-shifters that allow it to work over an input voltage range of 2.5–5.5 V, and the 0.1″ pin spacing makes it easy to use with standard solderless breadboards and 0.1″ perfboards.

Clearance: This board is being replaced by the newer L3GD20H carrier.

The Pololu MinIMU-9 v2 is an inertial measurement unit (IMU) that packs an L3GD20 3-axis gyro and an LSM303DLHC 3-axis accelerometer and 3-axis magnetometer onto a tiny 0.8″ × 0.5″ board. An I²C interface accesses nine independent rotation, acceleration, and magnetic measurements that can be used to calculate the sensor’s absolute orientation. The module includes a voltage regulator and a level-shifting circuit that allows operation from 2.5 to 5.5 V.

Clearance: This board is being replaced by the newer MinIMU-9 v3.

This 12 V linear actuator can be used in a variety of heavy-duty applications. The motor has 20:1 reduction gearbox that gives the actuator a dynamic load rating of 110 lbs (50 kg) and a maximum speed of 0.5 in/s (1.3 cm/s), and it is rated to withstand up to 500 lbs when not moving. Limit switches at each end make the actuator easy to control over its full range of motion, and the worm drive ensures that the shaft will hold its position even when unpowered. This version has a 4-inch stroke and no potentiometer.

This 12 V linear actuator can be used in a variety of heavy-duty applications. The motor has 20:1 reduction gearbox that gives the actuator a dynamic load rating of 110 lbs (50 kg) and a maximum speed of 0.5 in/s (1.3 cm/s), and it is rated to withstand up to 500 lbs when not moving. Limit switches at each end make the actuator easy to control over its full range of motion, and the worm drive ensures that the shaft will hold its position even when unpowered. This version has a 6-inch stroke and no potentiometer.

This 12 V linear actuator can be used in a variety of heavy-duty applications. The motor has 20:1 reduction gearbox that gives the actuator a dynamic load rating of 110 lbs (50 kg) and a maximum speed of 0.5 in/s (1.3 cm/s), and it is rated to withstand up to 500 lbs when not moving. Limit switches at each end make the actuator easy to control over its full range of motion, and the worm drive ensures that the shaft will hold its position even when unpowered. This version has a 8-inch stroke and no potentiometer.

This 12 V linear actuator can be used in a variety of heavy-duty applications. The motor has 20:1 reduction gearbox that gives the actuator a dynamic load rating of 110 lbs (50 kg) and a maximum speed of 0.5 in/s (1.3 cm/s), and it is rated to withstand up to 500 lbs when not moving. Limit switches at each end make the actuator easy to control over its full range of motion, and the worm drive ensures that the shaft will hold its position even when unpowered. This version has a 10-inch stroke and no potentiometer.

This 12 V linear actuator can be used in a variety of heavy-duty applications. The motor has 20:1 reduction gearbox that gives the actuator a dynamic load rating of 110 lbs (50 kg) and a maximum speed of 0.5 in/s (1.3 cm/s), and it is rated to withstand up to 500 lbs when not moving. Limit switches at each end make the actuator easy to control over its full range of motion, and the worm drive ensures that the shaft will hold its position even when unpowered. This version has a 12-inch stroke and no potentiometer.

This 12 V linear actuator can be used in a variety of heavy-duty applications. The motor has 5:1 reduction gearbox that gives the actuator a dynamic load rating of 34 lbs (15 kg) and a maximum speed of 1.7 in/s (4.3 cm/s), and it is rated to withstand up to 450 lbs when not moving. Limit switches at each end make the actuator easy to control over its full range of motion, and the worm drive ensures that the shaft will hold its position even when unpowered. This version has a 4-inch stroke and no potentiometer.

This 12 V linear actuator can be used in a variety of heavy-duty applications. The motor has 5:1 reduction gearbox that gives the actuator a dynamic load rating of 34 lbs (15 kg) and a maximum speed of 1.7 in/s (4.3 cm/s), and it is rated to withstand up to 450 lbs when not moving. Limit switches at each end make the actuator easy to control over its full range of motion, and the worm drive ensures that the shaft will hold its position even when unpowered. This version has a 12-inch stroke and no potentiometer.

This gearbox has four possible gear ratios, including the highest gear ratio of Tamiya’s gearbox series, 5402:1. The other options are 126:1, 441:1, and 1543:1. This gearbox also features a worm gear, which locks the output shaft when the motor is not turning.

Tamiya’s wall-hugging mouse is a fun and easy-to-build kit that’s great for new robot enthusiasts, and it can serve as a unique, hackable robot chassis for more advanced users. The mouse has no digital electronics; rather, a simple wire bumper along its side directs current to one of two motors to keep the mouse moving along the wall. The mouse features a hard plastic shell and runs on one alkaline AA battery.

Tamiya’s wall-hugging ladybug is a fun and easy-to-build kit that’s great for new robot enthusiasts, and it can serve as a unique, hackable robot chassis for more advanced users. The ladybug has no digital electronics; rather, a simple wire bumper along its side directs current to one of two motors to keep the ladybug moving along the wall. The ladybug features a hard plastic shell and runs on one alkaline AA battery.

Great for learning the basics of gears and linkages, this Tamiya kit contains all the parts necessary to make a remote controlled chassis with a ping pong ball collecting appendage. The instructions include directions for assembling the kit with either an arm, bucket, or shovel, and they include directions for a ping pong ball collecting competition.

Great for learning the basics of gears and linkages, this Tamiya kit contains all the parts necessary to make a remote controlled crawler that picks up ping pong balls. The instructions include directions for assembling the kit with either an arm, bucket, or shovel for collecting ping pong balls.

This versatile, high-efficiency gearbox lets you build one of the following gear ratios: 11.6:1, 29.8:1, 76.5:1, 196.7:1, 505.9:1, and 1300.9:1. Whatever your application, chances are that one of the configurations will do the job.

Frustrated by those cheap, low-voltage motors that require too much current? Here’s the answer: a low-voltage motor controller designed specifically for those toy motors. With all of the convenience of the Pololu dual serial motor controllers and the added ability to deliver 5 amps per motor with no minimum motor voltage, this dual serial motor controller has you covered.

The Pololu AltIMU-10 is an inertial measurement unit (IMU) and altimeter that features the same L3GD20 gyro and LSM303DLHC accelerometer and magnetometer as the MinIMU-9 v2, and adds an LPS331AP digital barometer. An I²C interface accesses ten independent pressure, rotation, acceleration, and magnetic measurements that can be used to calculate the sensor’s altitude and absolute orientation. The board operates from 2.5 to 5.5 V and has a 0.1″ pin spacing.

Clearance: This board is being replaced by the newer AltIMU-10 v3.

The Tamiya 70111 sports tire set contains two attractive racing-style wheels, each 56 mm in diameter and 25 mm wide. These wheels are compatible with all Tamiya gearbox kits.

The two extremely springy tires in the Tamiya 70096 off-road tires set are about 50 mm in diameter and 30 mm wide. Use these if you want your robot to have a soft, air-cushioned ride across rough terrain. (Compatible with the Tamiya gearbox numbers 70093, 70097, 70103, and 70110, 70167, and 70168).

The Line Tracing Snail is an excellent, low-cost robot for a new robotics enthusiast that has no previous experience with robots or electronics. All electronics are completely pre-assembled, and mechanical assembly is very straightforward. The snail has two speeds, and for added fun and entertainment, the eye stalks wiggle back and forth as the robot runs.

This compact sonar range finder by Maxbotix detects objects from 0 to 6.45 m (21.2 ft) with a resolution of 2.5 cm (1") for distances beyond 15 cm (6"). Unlike other sonar range finders, the LV-MaxSonar has virtually no dead zone: it can detect even small objects up to and touching the front sensor face!

The EZ0, EZ1, EZ2, EZ3, and EZ4 versions have progressively narrower beam angles.

This compact sonar range finder by Maxbotix detects objects from 0 to 6.45 m (21.2 ft) with a resolution of 2.5 cm (1") for distances beyond 15 cm (6"). Unlike other sonar range finders, the LV-MaxSonar has virtually no dead zone: it can detect even small objects up to and touching the front sensor face!

The EZ0, EZ1, EZ2, EZ3, and EZ4 versions have progressively narrower beam angles.

This compact sonar range finder by Maxbotix detects objects from 0 to 6.45 m (21.2 ft) with a resolution of 2.5 cm (1") for distances beyond 15 cm (6"). Unlike other sonar range finders, the LV-MaxSonar has virtually no dead zone: it can detect even small objects up to and touching the front sensor face!

The EZ0, EZ1, EZ2, EZ3, and EZ4 versions have progressively narrower beam angles.

This compact sonar range finder by Maxbotix detects objects from 0 to 6.45 m (21.2 ft) with a resolution of 2.5 cm (1") for distances beyond 15 cm (6"). Unlike other sonar range finders, the LV-MaxSonar has virtually no dead zone: it can detect even small objects up to and touching the front sensor face!

The EZ0, EZ1, EZ2, EZ3, and EZ4 versions have progressively narrower beam angles.

Clearance: This simple DIP breakout board from SparkFun for the Roving Networks RN-41 Bluetooth module lets you add a Bluetooth interface to a device that has a 3.3V serial port. Two 0.1" headers spaced 0.8" apart makes it easy to use with standard solderless breadboards and 0.1" perfboards. All pertinent pins are broken out and labeled. The RN-41 Bluetooth module on this carrier has firmware version 4.77.

Note: A newer module with firmware version 6.15 is now available, and this part is on clearance.

The Tamiya 70100 Track and Wheel Set allows for a large degree of adjustability and creativity in designing your own robot. The set includes a variety of track lengths, sprockets, and wheels that are compatible with multiple Tamiya products.

The Tamiya 70101 truck tire set contains four 36 mm-diameter wheels with hard, rubber, 16 mm-wide treads. Our small round robot chassis is designed to use a pair of these wheels, which are great for making small robots! (Compatible with the Tamiya gearbox numbers 70093, 70097, 70103, and 70110, 70167, and 70168).

The single gearbox is perfect if you like the gear ratio options of the 70168 double gearbox but need just one motor or added flexibility in positioning multiple output shafts. Available gear ratios are: 12.7:1, 38:1, 115:1, or 344:1.

The first in Tamiya’s “high efficiency” series, the planetary gearbox features two 4:1 and two 5:1 stages that can be combined in any way you like—you can even combine two kits to get really huge gear ratios. The output is always conveniently on the same axis as the motor shaft. Available gear ratios are 4:1, 5:1, 16:1, 20:1, 25:1, 80:1, 100:1, and 400:1.

This machined aluminum bracket allows the Concentric LD series linear actuators to be mounted to a structure. Complete mounting hardware is included. Two brackets are required for mounting each actuator.

Unlike the other gearboxes in Tamiya’s series, the universal gearbox has a thin metal frame, making it the smallest Tamiya gearbox. The final two gears are metal, making for a tough output. A worm gear allows for the high gear ratio options of 101:1, 269:1, and 719:1.

The RW2i rubber wheel features an internal set screw ideal for designs with space constraints. The 1.23-inch diameter wheel by Solarbotics is made for 3 mm diameter output shafts. These wheels are sold individually, NOT in pairs.

With possible gear ratios of 41.7:1 and 64.8:1, the high-power gearbox is well-suited for most vehicles that require a balance of speed and torque.

The primary feature of this high-efficiency gear box is a worm gear, which locks the output shaft whenever the motor is not turning. The high gear ratios of 216:1 or 336:1 make this gearbox appropriate for small walking robots, lifting mechanisms, and other applications where high torque is desired.

This wire stripper cleanly strips the tips of 16-26 AWG wires.

This discounted combination of Tamiya’s twin-motor gearbox, ball caster, and truck tires is meant for use with two Pololu round robot chassis.

Snap Circuits Jr. 100-in-1 includes over 30 plastic parts and over 100 sample projects. The snap-together electronic blocks are mounted on plastic pieces that can be used again and again to form many exciting and educational circuits.

The Solar Power kit guides you through 150 activities that show how to transfer solar energy into other forms of energy. With the included parts you can build a solar electric generator, motor, water heater, thermometer, galvanometer and many other devices.

Snap Circuits 300-in-1 includes over 55 plastic parts and over 300 sample projects. The snap-together electronic blocks are mounted on plastic pieces that can be used again and again to form many exciting and educational circuits.

The OWI-535 Robotic Arm Edge Kit is a remote-controlled robotic arm kit with five degrees of freedom, a 3.5oz (100g) lifting capacity, and an LED light. Using five motors with gearboxes, the Edge has a 120° wrist motion, a 300° elbow motion, a 180° shoulder motion, a 270° base motion, and a 0-1.77" (0-4.5cm) gripping motion.

The RC Snap Circuits Rover is a mobile, radio-controlled Snap Circuits platform. Build the 23 included projects and create many of your own circuits with the ample circuit-building space on top of this four-wheeled chassis. The included manual has projects that explore the fundamentals of circuit design and radio control.

Snap Circuits 500-in-1 includes over 65 plastic parts and over 500 sample projects. The snap-together electronic blocks are mounted on plastic pieces that can be used again and again to form many exciting and educational circuits.

The Deluxe RC Snap Circuits Rover is a mobile, radio-controlled Snap Circuits platform. Build the 63 included projects (including a rover that shoots a disc at the push of a button!) and create many of your own circuits with the ample circuit-building space on top of this four-wheeled chassis. The included manual has projects that explore the fundamentals of circuit design and radio control.

Learn electronics with the Elenco 500-In-One Electronic Project Lab! This kit includes everything you need to get started building your own electronic circuits. The largest of the project labs, this kit contains all the fun and education of the smaller kits, and takes your education a step further by teaching its users about microcontrollers and programming. This kit includes the six required AA batteries.

This discounted combination of Tamiya’s twin-motor gearbox, ball caster, and truck tires is meant for use with one Pololu round robot chassis.

Learn electronics with the Elenco 200-In-One Electronic Project Lab! This kit includes everything you need to get started building your own electronic circuits. Components such as resistors, capacitors, LEDs, ICs and more are securely attached to the electronic lab so you can spend less time searching for components and more time learning how to build that next circuit! This kit requires six AA batteries (not included).

Learn electronics with the Elenco 75-In-One Electronic Project Lab! This kit includes everything you need to get started building your own electronic circuits. Components such as resistors, capacitors, LEDs, ICs and more are securely attached to the electronic lab so you can spend less time searching for components and more time learning how to build that next circuit! This kit requires four AA batteries (not included).

The Solarbotics RW2 is a 1.23-inch diameter rubber wheel for 3 mm diameter output shafts. These wheels are sold individually, NOT in pairs.

This semiconductor gas sensor detects the presence of alcohol gas at concentrations from 0.04 mg/L to 4 mg/L, a range suitable for making a breathalyser. The sensor’s simple analog voltage interface requires only one analog input pin from your microcontroller.

The Arduino Mega 2560 R3, the successor to the Arduino Mega, is a microcontroller board based on a ATmega2560 AVR microcontroller. It has 70 digital input/output pins (of which 14 can be used as PWM outputs and 16 can be used as analog inputs), a 16 MHz resonator, a USB connection, a power jack, an in-circuit system programming (ICSP) header, and a reset button. The Arduino has an extensive support community, which makes it a very easy way to get started working with embedded electronics.

Tamiya’s steel-ball caster is a good way to give a “third wheel” to a small robot powered by a differential drive. The kit comes with enough parts to make two casters, either 25 mm or 35 mm in height.

The Arduino Uno R3 is a microcontroller board based on a removable, dual-inline-package (DIP) ATmega328 AVR microcontroller. It has 20 digital input/output pins (of which 6 can be used as PWM outputs and 6 can be used as analog inputs). Programs can be loaded on to it from the easy-to-use Arduino computer program. The Arduino has an extensive support community, which makes it a very easy way to get started working with embedded electronics. The R3 is the third, and latest, revision of the Arduino Uno.

Use the pair of tires in the Tamiya 70145 narrow tire set for small and medium-sized robots that must make precise movements. With a 58 mm diameter and solid, rounded, 16 mm treads, these wheels will let your robot turn with little friction, even on rough surfaces like carpet. These wheels are compatible with all Tamiya gearbox kits.

The Raspberry Pi is a credit card-sized computer with an ARM processor that can run Linux. This item is the Raspberry Pi Model B, revision 2.0, which has 512 MB of RAM, an ethernet port, HDMI output, RCA composite video output, audio output, two USB ports, and 0.1″-spaced pins that provide access to general purpose inputs and outputs (GPIO). The Raspberry Pi requires an SD card with an operating system on it (not included). The Raspberry Pi is very popular, with lots of example projects and information available online.