An “EVB” Kickstarter project replaces the Lego Mindstorms EV3 robot’s ARM9 brick with a BeagleBone Black, adding performance, expandability, and sensors.
Lego’s EV3 brick
When Lego added a Linux-based “Brick” computer to its modular, open source Lego Mindstorms robot platform, we were psyched, but were also somewhat disappointed it was only a modest ARM9-based device. Now, a startup called Fatcatlab has found Kickstarter success with an EVB computer you can use in place of the Brick that is designed to plug in a BeagleBone Black for a much faster 1GHz Cortex-A8 experience.
The EVB project, has received over $33,000 in pledges, more than four times its $8,000 goal, and there are still six days left. (The project got a boost from its selection as a Kickstarter Staff Pick.) Prices start at $68 for the EVB cape board (minus the BeagleBone Black itself), and there’s a $208 model that includes seven user selected sensor modules. The EVB kit also includes an LCD screen, battery packs, sensor wires, and an acrylic case.
Lego’s EV3 brick (left) compared to Fatcatlab’s EVB
(click image to enlarge)
Note that while the EVB is said to replace the brain of the EV3, the EV3’s sensor board is still available. So, aside from speed, including faster boot up, the main benefit here is that you are adding an additional sensor board, enabling a wider range of sensors simultaneously. In addition, because the BeagleBone Black supports a large ecosystem of additional cape add-ons, you can trick out your Lego Mindstorms robot with a wide array of add-ons.
To ensure compatibility, the EVB cape mimics the GPL-licensed internal specs of the EV3, aside from the ARM9-based 300MHz Texas Instruments AM1808 processor. However, it provides a higher resolution, 220 x 176-pixel LCD display that also adds color support and backlighting. The EVB also enables new functions provided by the BeagleBone Black, including a 10/100 Ethernet port and a TTL serial port.
EVB display, angle view, and side view
(click images to enlarge)
WiFi, which is available with the EV3, is said to be under development for the EVB. Unlike the EV3, there’s no Bluetooth or I2C support. Also, there’s only one button instead of six, although the EVB adds a multifunction switch, which would appear to mitigate this.
The specs are ambiguous in some places. For example, it’s unclear whether the EVB can make use of the EV3’s four USB ports or GPIO. Neither is listed as an EVB feature.
The specs of the EVB are listed in one place as supporting a 720MHz BeagleBone Black, and 1GHz in another, so it would appear the device supports either the original BeagleBone Black, as well as the newer BeagleBone models such as the Rev C. This configuration would give you a 1GHz TI AM3359 SoC, 512MB of RAM, and 4GB of eMMC flash. By comparison, Lego’s EV3 is limited to 64MB RAM.
The EVB supports all the LEGO Mindstorms sensors, says Fatcatlab. In addition, Fatcatlab offers seven new optional sensors, which can also be used with a standard EV3-equipped Lego Mindstorms set-up.
The optional sensor modules include:
- ADC Module — The ADC Module lets you “use all the Arduino analog sensors on the EVB or EV3,” says Fatcatlab. It detects two channels of voltage from 0 to 3300mV with 10-bit (3.2mV) accuracy.
- Gesture Sensor — In addition to detecting six kinds of hand gestures, it can measure RGB color value and detect proximity.
- Light Sensor — This module measures light intensity with a range of 0-65535 lux.
- Pressure/Altitude Sensor — This air pressure and altitude sensor offers a 300-1100hPa range with ±0.12hPa (±1.0m) accuracy.
- IR Receiver — The beta-stage EVB’s infrared receiver module will support a 21-button remote.
- 9DOF Sensor — This nine degrees of freedom module provides tri-axis angular rate, accelerometer, and compass.
- Temperature&Humidity Sensor — This module’s temperature accuracy is rated at ±0.3deg, and the humidity accuracy at ±3.0%RH.
The project’s video comparing the standard EV3 brick to its EVB alternative appears below.
EV3 and EVB comparison
Kickstarter funding for the EVB is available through Jan. 26 starting at $68 minus the BeagleBone Black. Products are expected to ship in April. (We noticed, however, that the BeagleBone Black is referred to several times as the “Beaglebong Black,” so it might take just just a little longer.) More information may be found at the EVB Kickstarter page, as well as at the Fatcatlab website.