RobotBits.co.uk has begun selling an open source mobile robotics kit from Frindo.org available with an Arduino Duo, or as an under-$100 model that lets you add your own Arduino and/or Raspberry Pi. The Frindo robotics platform, which appears to be about 100mm in diameter, is billed as being more robust than most low-cost educational robots, and is optionally available with a motor controller board and sensor bundle.

Frindo.org and its distributor and unofficial sponsor RobotBits.co.uk plan to formally launch the Frindo robot in several weeks once more kits are in stock, according to an email from Jonathan Luke, the founder of both Frindo.org and RobotBits.co.uk. However, the kit is already out of the bag, so to speak, now that robot kit retailer RobotBits.co.uk has begun selling the Frindo.

Frindo.org’s Frindo robotics platform

The initial designs include an Arduino microcontroller and Arduino-based RobotShield – the Frindo Arduino kit starting at 65 U.K. Pounds ($105) – as well as a barebones model for 54 Pounds ($87) with mounting for either (or both) an Arduino or Raspberry Pi single board computer. According to Luke, the plan is to develop mounting kits for other open source controller boards, including the BeagleBone.

One upcoming kit design will offer both an Arduino and Raspberry Pi working together. In the meantime, tips are provided for cobbling together a design with both boards on your own. In this way, you don’t have choose between the Linux OS, web support, and image processing of the Raspberry Pi on the one hand, or the greater real-time motor control of the Arduino Uno board on the other.

RobotShield for Frindo Arduino kit
(click image to enlarge)

The Arduino model ships with an Arduino Shield called the RobotShield that provides the motor circuit. In the Pi-only design, the Raspberry Pi is integrated with a breadboard that holds a motor circuit.

The RobotShield was developed by RobotBits.co.uk, and has been donated with open source licensing and schematics to the Frindo.org project. It offers a dual bi-directional motor driver circuit running on 2 Amp peak power and 1.1 Amp continuous. The RobotShield is further equipped with 3-pin server headers for I/O, including serial, SPI, and I2C, with the latter offering integrated pull-up resistors. A reset switch and thermal overload protection are also provided.

The Frindo kit includes two wheels, a battery pack for six AA batteries, two motors, and two pre-drilled chassis plates made of clear or black acrylic. The robot provides all the screws, cables, and other components you would need, according to a hands-on review from LinuxUser’s Russell Barnes.

The review praises the robot for its “two high-quality Pololu micro-motors complete with compatible mounting brackets, wheels and a pan-and-tilt mounting kit.” Adds Barnes, “Frindo is clearly the most comprehensive robot chassis we’ve seen.” This thoroughness extends to the website, where there are numerous schematics and tutorials, as well as some open source “avoider” example code for the Pi.

Luke developed the Frindo idea based on customer complaints at RobotBits.co.uk. The Frindo “is not intended to be the lowest-cost platform, but is very robust,” says Luke. “In the past, a lot of feedback that I have received from my customers at RobotBits, particularity in education, has been around the fragility of existing platforms such as magician and 3Pi.”

Barnes appears to agree, citing the Frindo’s pre-soldered motors and solid construction. “Its thick, sturdy chassis plates and two-tier design ensure it’s very solid and stable and the provided motors and sensors performed perfectly,” he writes. “It’s clearly built to a high standard and could easily withstand the kind of punishment educational applications would undoubtedly entail.”

Frindo with Raspberry Pi and webcam

A deluxe model adds a sensor array with Sharp infrared analog sensors and mounting brackets. In addition, the Frindo.org site shows how to hook up the Pi-based version with a webcam (see image above), although the camera is not currently available as part of a kit.

Luke says he wants to “distance the project from RobotBits,” gain more distributors, and expand to new controller boards. He also wants to build up an open source developer community, and says Frindo.org is in particular need of software developers.
 

Further Information

Limited supplies of Frindo kits are available at RobotBits.co.uk starting at 54 Pounds ($87) for the chassis-only model, and moving up to 65 Pounds ($105) for the Frindo Arduino kit, and 95 Pounds ($153) for the Frindo Arduino kit with sensor array. More information may be found at Frindo.org.