High-Speed Laser Range Finder Board with IMU

Integrated

The NavRanger-OEM

The NavRanger-OEM combines a 20,000 samples per second laser range finder with a nine-axis inertial measurement unit (IMU) on a single 3“ × 6“ (7.7 × 15.3 cm) circuit board. The board features I/O resources and processing capability for application-specific control solutions.

The NavRanger‘s laser range finder measures the time of flight of a short light pulse from an IR laser. The time to digital converter has a 65-ps resolution (i.e., approximately 1 cm). The Class 1M laser has a 10-ns pulse width, a 0.8 mW average power, and a 9° × 25° divergence without optics. The detector comprises an avalanche photo diode with a two-point variable-gain amplifier and variable threshold digitizer. These features enable a 10-cm × 10-cm piece of white paper to be detected at 30 m with a laser collimator and 25-mm receiver optics.

The range finder includes I/O to build a robot or scan a solution. The wide range 9-to-28-V input supply voltage enables operation in 12- and 24-V battery environments. The NavRanger‘s IMU is an InvenSense nine-axis MPU-9150, which combines an accelerometer, a gyroscope, and a magnetometer on one chip. A 32-bit Freescale ColdFire MCF52255 microcontroller provides the processing the power and additional I/O. USB and CAN buses provide the board’s high-speed interfaces. The board also has connectors and power to mount a Digi International XBee wireless module and a TTL GPS.

The board comes with embedded software and a client application that runs on a Windows PC or Mac OS X. It also includes modifiable source code for the embedded and client applications. The NavRanger-OEM costs $495.

Integrated Knowledge Systems, Inc.
www.iknowsystems.com

Scott Garman, Technical Evangelist

This article was a preview of an upcoming interview in the February issue of Circuit Cellar. The full interview is now available here.
Garman_web

Scott Garman is a Portland, OR-based Linux software engineer. Scott is very involved with the Yocto Project, an open-source collaboration that provides tools for the embedded Linux industry. Scott tells us about how he recently helped Intel launch MinnowBoard, the company’s first open-hardware SBC. The entire interview will be published in Circuit Cellar’s February issue.—Nan Price, Associate Editor

NAN: What is the Yocto Project?

 SCOTT: The Yocto Project is centered on the OpenEmbedded build system, which offers a tremendous amount of flexibility in how you can create embedded Linux distros. It gives you the ability to customize nearly every policy of your embedded Linux system.

I’ve developed training materials for new developers getting started with the Yocto Project, including “Getting Started with the Yocto Project—New Developer Screencast Tutorial.”

MinnowBoardWEB

Scott was involved with a MinnowBoard robotics and computer vision demo at LinuxCon Japan, May 2013.

NAN: Tell us about Intel’s recently introduced the MinnowBoard SBC.

SCOTT: The MinnowBoard is based on Intel’s Queens Bay platform, which pairs a Tunnel Creek Atom CPU (the E640 running at 1 GHz) with the Topcliff Platform controller hub. The board has 1 GB of RAM and includes PCI Express, which powers our SATA disk support and gigabit Ethernet. It’s an SBC that’s well suited for embedded applications that can use that extra CPU and especially I/O performance.

MinnowBoardOWI_web

Scott worked on a MinnowBoard demo built around an OWI Robotic Arm.

The MinnowBoard also has embedded bus standards including GPIO, I2C, SPI, and even CAN (used in automotive applications) support. We have an expansion connector on the board where we route these buses, as well as two lanes of PCI Express for custom high-speed I/O expansion.

NAN: What compelled Intel to make the MinnowBoard open hardware?

SCOTT: The main motivation for the MinnowBoard was to create an affordable Atom-based development platform for the Yocto Project. We also felt it was a great opportunity to try to release the board’s design as open hardware.