Surveyor Robotics Journal

Upgrading an SRV-1 robot to stereo vision ... - 24 Aug 2008

Here is a brief description of the process to upgrade an SRV-1 Blackfin robot to stereo vision. We unsolder the motor leads and battery wire from the original motor controller or combo motor/radio board, remove the circuit boards, then check the wire lengths to make certain they will reach the connectors on the underside of the SVS controller. More often than not, we do have to lengthen those wires, especially if we are mounting a pan/tilt head to the robot base.

Note that we have added connectors to the motor and power wires, using Jameco 100766 connector pins with Jameco 100812 plastic blocks. Also, we have added somewhat taller standoffs to keep the antenna cable and 32-pin headers clear of the robot base. For the original dual-motor bases, we add 7/16" standoffs. For the new quad-motor base, we would use 1" standoffs.

The Blackfin and Matchport should be running at 2500kbps with latest firmware (srv-blackfin-081408.zip at time of this post). The final step is to move the Blackfin camera, Matchport radio, and dipole antenna cable from the original boards and base to the SVS board before mounting the SVS to the robot base. In some cases, we also have to change the lens on the original camera board from 6.5mm to the newer 3.5mm wide angle lens in order to match the second Blackfin camera.

Here is the end result of an upgrade ...

It is actually the second upgrade for this particular robot, which belongs to RoboRealm. It started life as an SRV-1 ARM7 with Zigbee a couple of years ago for use in their original SRV-1 support, and was upgraded to Blackfin with WiFi almost a year ago for development of their updated SRV-1 Blackfin support. Now it is headed back to them for development of stereo vision algorithms, and we look forward to the results !
(Posted Sun, 24 Aug 2008 12:05)

Surveyor SVS (stereo vision system) - first experiments with automated color segmentation for stereo disparity calculations - 20 Aug 2008

While others are working on much more sophisticated stereo disparity algorithms using host computing power, I thought we might be able to build some basic matching functions into the Blackfin firmware using simple color matching for correlating objects between the separate views. The key to this approach is to segment the images into a minimal set of colors that can be used for simple image comparisons.

Color segmentation is an interesting research problem which has led to the definition of a variety of color spaces, as discussed here and here, as well as a variety of feature processing models, as described here. One of the goals in creating the SRV-1 Blackfin and the SVS was to provide an easily accessible platform for experimenting with the color segmentation challenge.

As described above, a simple approach would minimize the number of colors in the corresponding stereo images and then look for matches. Below, you will see the original stereo pair (scaled down for this display), a 16 color segmentation that uses 4 luminance and 4 chrominance levels (2 bits Y, 1 bit U, 1 bit V - "211"), and a 16 color segmentation that uses 4 U and 4 V levels (2 bits U, 2 bits V, and no luminance component - "022").

The 211 approach seems to provide reasonable feature definition, but correlation of colors between left and right images isn't actually so great. The 022 approach doesn't seem to be making very good use of the range of colors, but the feature correlation almost looks usable. So the next step is to find a segmentation of the UV-only space that more efficiently maps actual colors. Along these lines, we divided the U and V color spaces into 16 segments each, and then built a tool to display the U vs V histogram in 2D.

The next step is to define a segmentation that looks for clustering or local maxima in the 2D histogram. So stay tuned ...
(Posted Wed, 20 Aug 2008 15:39)

Inertial Navigation + GPS + MicroSD Expansion Card for SRV-1 Blackfin Camera - 19 Aug 2008

This is very cool ! One of the developers working with the SRV-1 Blackfin Camera on the MIT SPHERES program has designed a new expansion card with support for a full suite of inertial sensors, compass, gps, and MicroSD storage.

Designated the SRV-1X, it includes:

16-bit dsPIC signal processor
34 GPIO (10 can be configured as 12-bit analog inputs)
MicroSD socket for up to 1GB storage
Open Source Firmware
Interface to SRV-1 Blackfin via 32-pin expansion bus

Optional features include:

GPS - select between Trimble Lassen iQ and u-blox LEA-5S
3-axis accelerometer
up to 3-axis gyroscope
2-axis magnetometer

The base board with dsPIC and MicroSD socket will cost $75, and additional sensors range in cost from $25 to $149. First boards will be available around August 26, and initial quantity is limited. Full pricing, specifications and ordering instructions are found at http://www.pericynthion.org/srv1x
(Posted Tue, 19 Aug 2008 10:58)

Progress with SRV-1 Blackfin Stereo Vision System - 11 Aug 2008

Sentience stereo vision software developer Bob Motram has been working for a few weeks with one of the prototype SRV-1 Blackfin stereo vision systems, and he has already developed a slick calibration procedure to correct for wide-angle lens distortion, as described here -
http://streebgreebling.blogspot.com/2008/08/surveyor-project-calibration.html

Initial tests of stereo correspondence procedures have started, as discussed here -
http://streebgreebling.blogspot.com/2008/08/visual-disparity.html

You can track Bob's progress via his blog or via his source code.
(Posted Mon, 11 Aug 2008 13:01)

Live Internet control of SRV-1 Blackfin Robots - BP Explorer - 11 Aug 2008

This is a fantastic demo of SRV-1 robot remote control through the Internet - www.bpexplorer.com.au

The images above show some fixed camera views of the "set" as well as snapshots captured by one of the robots. Five robots are available for control at any time, though sometimes the queue to access the site is quite long. The BP Explorer demo is intended to highlight some of BP's green technologies, including the solar panels that are used to recharge the robots. Kudos to the amazing job Ogilvy New Zealand did in putting this together for BP Australia.
(Posted Mon, 11 Aug 2008 11:34)

Unexpected application for SRV-1 Blackfin - MIT SPHERES - 29 Jul 2008

The SPHERES program at MIT's Space Systems Lab was developed to allow researchers to test control algorithms for satellite formation flight and constellation building in a long-term test environment on the International Space Station. Each SPHERES satellite is about 1ft in diameter and is fully self-contained with a flight computer, inertial sensors and a reaction control system using carbon dioxide gas. Three are flying on the Space Station right now, while three more are on the ground for testing and continued development.

The MIT group is using the SRV-1 Blackfin board sets to provide a vision system to SPHERES, which will allow several satellites to autonomously dock to several free-floating flexible beams, pick them up and connect them together forming a structure.

A full description of the program including videos is found here - http://ssl.mit.edu/spheres/
(Posted Tue, 29 Jul 2008 11:50)

SRV-1 Blackfin Stereo Camera with pan/tilt and robot mount - 23 Jul 2008

Mounting the stereo camera on a pan/tilt assembly attached to a robot base proved to be quite simple. We are using the Lynxmotion BPT-KT pan/tilt head with a couple of extra holes for 1/2-inch hex standoffs. The BPT-KT is a nice stable unit with good HS-422 servos.

We use 1-inch standoffs with a couple of aluminum strips to attach the pan servo to the top of the SRV-1 robot base. The 1-inch x 2-inch mounting pattern for the standoffs is identical for the original SRV-1 base and the new SRV-1Q base.

The servos are driven directly from the stereo camera board using TMR6 and TMR7 of the left Blackfin and can be controlled directly via the 's' command in the control protocol with no modification to firmware. Only change from the original SRV-1 setup is longer motor and battery power wires.
(Posted Wed, 23 Jul 2008 13:40)

Robot Magazine interested in SRV-1 Blackfin university users - 18 Jul 2008

Tom Atwood, Editor-in-Chief of Robot Magazine, is interested in talking with university instructors, researchers and students who are working with SRV-1 Blackfin robots and controllers to feature their work in the magazine's "Robot Spotlight" section.

If you would like to participate, please send an email to support@surveyor.com with your contact information and a brief description of your SRV-1 Blackfin usage. Your submission doesn't have to be limited to university applications, as other uses might catch their interest, but this seems to be their primary focus.

(Posted Fri, 18 Jul 2008 20:43)

First frames from prototype SRV-1 Blackfin Stereo Camera - 14 Jul 2008

left right

Prototype boards just arrived and first tests were successful, with both cameras transmitting through the shared Matchport (simultaneous feeds shown above in left and right windows). We still need to test the servo or h-bridge interfaces, but the voltages look good. Only issue is that we have to manually reset both processors after power-up - most likely issue is a collision on the SPI channels as both Blackfins simultaneously boot from SPI flash. Not certain yet how we want to deal with that ...

Discussion on this project continues on the Surveyor Robotics Forum.
(Posted Mon, 14 Jul 2008 20:46)

Surveyor Corp and Inertia Labs team to build new quad-motor version of SRV-1 Blackfin Robot
- 13 Jul 2008

The new quad-motor version of the SRV-1 Blackfin Robot is now shipping. Created through cooperation between Surveyor Corporation and Inertia Labs, the new robot is smaller and lighter than the original SRV-1, measuring 5 x 4 x 3-inches @ 13-oz (12 x 10 x 8-cm @ 350gm) with a more compact Li Poly battery pack and quad-motor drive with tank-style treads.

Inertia Labs is the highly regarded developer of Antweight fighting robots as well as full-sized BattleBots champions Toro, Matador and T-Minus. They are very skillful robot designers and fabricators.

The new SRV-1 Blackfin Robot, designated SRV-1Q, is now available directly from Surveyor, Inertia Labs, and resellers worldwide.
(Posted Sun, 13 Jul 2008 20:31)

Prototype layout is finished for stereo Blackfin camera board - 07 Jul 2008

Prototype boards should be here by end of next week. Here are the Eagle files:

http://www.surveyor.com/blackfin/bfin-stereo-v1.sch
http://www.surveyor.com/blackfin/bfin-stereo-v1.sbrd

There is a continuing discussion of this project on the forum.
(Posted Mon, 07 Jul 2008 08:00)

Some thoughts about a stereo version of SRV-1 Blackfin Camera - 01 Jul 2008

There has been an active discussion on the Surveyor Robotic Forum about the possibility of a stereo version of the SRV-1 Blackfin Camera - http://www.surveyor.com/cgi-bin/yabb2/YaBB.pl?num=1210703461. It looks like we will be moving ahead with this project and welcome comments on the design (to be published in Eagle 5 PCB format).

Here is a mockup of the stereo board set created by setting 3 existing SRV-1 radio boards side-by-side. I believe this is pretty close to how the final layout will look.

The dimensions seem reasonable - overall board size will be 6" x 2.5" (155 x 65mm), with the lens centers separated approximately 4.5" (115mm). Here are some current thoughts on the design:

maintain the current mounting pattern (1" x 2") in the center section, but maybe add some mounting holes under the cameras
provide a mounting hole for the wifi antenna
possibly provide an H-bridge motor drive and a pair of transistor drivers from each camera, duplicating the existing radio/motor control functions
define a different 32-pin header to bring out signals from both cameras and possibly the Matchport
interconnect the two cameras via SPI and GPIO. Also, camera #1 will connect to Matchport serial channel 1 (port 10001), and camera #2 will connect to Matchport serial channel 2 (port 10002).
add a 5V regulator for driving servos (e.g. pan/tilt)

As soon as the new Eagle 5 arrives (maybe today), we will start working on this. The main question will be how to allocate signals to the board's expansion header.

Part of the concept is to design this as a drop-in replacement for the existing SRV-1 controller, so users who already have the SRV-1 Blackfin can use their existing Blackfin camera and Matchport and will need only an additional Blackfin camera along with the stereo board. For new users, a complete stereo camera setup with both cameras and Wifi will probably cost in the ballpark of $550.
(Posted Tue, 01 Jul 2008 12:00)

Archiving and command line options added to SRV1Test.java TCP/UDP console - 19 Jun 2008

We have made a few changes to the SRV1Test.java console application, adding the ability to use the command line to override default configuration variables and archive the incoming video frames:

The default values are -remote_addr 169.254.0.10, -remote_port 10001, -protocol TCP, -local_port 10001.

The -archive option causes SRV1Test to capture all incoming frames to the specified directory. Each frame will be stored with a sequential time tag, so you can use any of a variety of conversion programs to transform the JPEG frames to a movie format such as Quicktime, AVI, MPEG, Flash, e.g.

Here's the download link for SRV1Test.java:

http://www.surveyor.com/blackfin/SRV1Test.java
(Posted Thu, 19 Jun 2008 16:30)

New Java-based test application for SRV-1 Blackfin - supports UDP & TCP connections - 12 Jun 2008

We now have a simple java-based test application for UDP and TCP connections with the Matchport and SRV-1 Blackfin.

SRV1Test.java source code is found here:

        http://www.surveyor.com/blackfin/SRV1Test.java

The protocol, IP address, and ports are hard-coded in the first lines of the SRV1Test.java source code:

and provided the Java SDK is installed, the application is easy to compile and run:

        javac SRV1Test.java
        java SRV1Test

The program quickly connects to the designated SRV-1 Matchport and begins to pull frames. While connected, the user can send SRV_protocol commands in ASCII or Hex and view the results.

The Matchport can be configured for a UDP connection via the Matchport's web interface -

Note that in UDP mode, the Matchport does not support hardware flow control, and we have seen that it can't keep up with the 2500kbps interface, though it works fine at 921kbps. We are looking at ways to overcome this flow control issue in the SRV-1 Blackfin firmware, but for the moment, please note this limitation.

Again, here is the source code download link:

        http://www.surveyor.com/blackfin/SRV1Test.java
(Posted Thu, 12 Jun 2008 12:49)

Default Matchport configuration for SRV-1 Blackfin is now 2500kbps - 24 May 2008

The special version of Matchport firmware (matchport-6500GE.rom) that Lantronix built for us has proven to be very robust, and in many ways, superior in performance to the default 6.6.0.0 firmware. As such, shipments of the SRV-1 Blackfin robot and SRV-1 Blackfin camera w/WIFI will henceforth be preconfigured with this 6500GE firmware on the Matchport and 2500kbps firmware on the Blackfin.

Note that if you check the Matchport settings through the web interface, it will show the CPU Performance as medium and the baud rate at 9600. You can ignore these settings. In case you inadvertently reset the Matchport, you can recover the settings via telnet to port 9999, using the instructions shown here - http://www.surveyor.com/cgi-bin/yabb2/YaBB.pl?num=1209480141

(Posted Sat, 24 May 2008 18:01)

Microsoft Robotics Studio 1.5 - test version of SRV-1 Blackfin support - 15 May 2008

We just posted a test version of SRV-1 Blackfin support in MSRS 1.5 on the Surveyor Robotics Forum - see http://www.surveyor.com/cgi-bin/yabb2/YaBB.pl?num=1210870698.

The "Teleoperation" service provides a nice joystick-like control interface and easy configuration. Many thanks to Trevor Taylor of Software Technology, Australia, for providing this support.

Trevor also provided support for the original ARM7-based SRV-1, as documented in his new book - "Professional Microsoft Robotics Developer Studio". Additional information on Trevor's work can be found here - http://www.soft-tech.com.au/MSRS/.
(Posted Thu, 15 May 2008 13:36)

Update for SRV-1 Blackfin command protocol specification - 11 May 2008

The command protocol specification for SRV-1 Blackfin firmware has been updated to include latest additions, and reorganized semi-alphabetically to be more readable / usable.

Latest version is found here -
http://www.surveyor.com/SRV_protocol.html
and here -
http://www.surveyor.com/blackfin/SRV_protocol_bf.html

(Posted Sun, 11 May 2008 12:13)

New Matchport / Zigbee radio board for SRV-1 Blackfin - 08 May 2008

Abe Howell's Robotics - www.abotics.com - has developed a new radio board for the SRV-1 Blackfin which hosts either the Lantronix Matchport 802.11b/g or Digi/Maxstream Zigbee 802.14 radio, and interfaces to a second microcontroller operating at 5V. As many microcontrollers operate at 5V instead of the 3.3V we use for the Blackfin, this level shifting a very nice feature.

The new board is open source, with all schematics published on the Abotics website, e.g. http://www.abotics.com/ExpressPCBs/OPEN_ROBOT_MATCHPORT_BOARD_SCHEMATIC.pdf and an assembly manual is provided here - http://www.abotics.com/MatchPort_PCB_Assembly.pdf.

Visit http://abotics.com/open_robot.htm for more project details.

We're really happy to see this board, as a number of our users are interfacing the SRV-1 Blackfin camera to other robot platforms with 5V logic. Also, this represents the first 3rd-party add-on board for the SRV-1 Blackfin, and we hope to see this trend continue.
(Posted Thu, 08 May 2008 20:23)

new visualization tool for color segmentation on SRV-1 Blackfin - 06 May 2008

A new version of test firmware has been posted, as described here on the Surveyor Robotics Forum. It adds a new visualization tool for color segmentation, allowing the user to view in real time the actual matches in color bins defined by the 'vc' or color command. For example, in this new firmware, if we defined the following colors -

vc0075225025100025100 (green)
vc1075225025100175250 (orange)
vc2075225100150175250 (red)
vc3075225150225025100 (blue)

and then issued the new 'g1' command, all of the pixels matching one of these color bins would be assigned a solid color (the midpoint of the range), and remaining pixels that don't match any colors would be painted black.

For example, using the above set of colors, we printed out this graphic from http://en.wikipedia.org/wiki/YUV

put the printout in front of the camera, and looked for pixel matches. Here's the image before color segmentation was enabled -

and the same camera view with color segmentation enabled -

Here's an archived video showing the tracking of an orange golf ball in real time - note how my fingers block out part of the shape. Clearly, the color ranges have not been optimized, but you get the idea -

http://www.surveyor.com/images/orange-ball-tracking.mov

This color segmentation visualization tool should help considerably in dialing in color ranges for object location / tracking tasks.
(Posted Tue, 06 May 2008 12:34)

Report from Maker Faire - 04 May 2008

We spent the day yesterday at Maker Faire, probably the largest DIY techno / craft / electronics gathering of its kind (60,000 projected attendees) anywhere. Lots of robots, a giant mousetrap, steam punk, an electric cupcake parade, r/c battleships battling with BB's, 800kV Van de Graff generator, flamethrowers, 20-ft homemade rockets, etc. Felt just like home ...

Main purpose of attending was to support demos given by Team FREDnet for their Google Lunar X-Prize entry - they had a small swarm of SRV-1 Blackfin robots available for test drives, including a couple of prototypes of a quad-motor version we're developing with Inertia Labs.

An SRV-1 Blackfin was also spotted in the RoboRealm booth, and there may have been other SRV-1's at the show.

At the other end of the faire from the FREDnet project, we got to hang out with Chris Anderson, editor-in-chief of Wired Magazine and author of The Long Tail at the geekdad.com booth. Chris is the creator of the DIYDrones, a very popular destination for UAV developers. In particular, Chris has been working on a couple of entry-level robotic blimps, and he asked us to bring YARB 1.0 to share the booth with BlimpDuino . There seems to be a lot of interest in robotic blimps, and it was fun to talk with Chris about a divide-and-conquer strategy for this as-yet-non-existent market.

The Maker Faire is still running today, though YARB 1.0 won't be there. Next time, we'll plan for a longer trip plus a logo on the blimp (as it was featured but unidentified in a G4TV interview).
(Posted Sun, 04 May 2008 13:20)

CIS1.5 Introduction to Programming using C++ (robotics application) - Brooklyn College (City University of New York) - 04 May 2008

Brooklyn College has built cross-platform (Win, Mac, Linux) console support for the SRV-1 Blackfin and ARM7 for use in their course - CIS1.5 Introduction to Computing Using C++. This is part of a larger robotics education program called robotics.edu, which is a shared spaced for curricular materials used in educational robotics classes for middle school and undergraduates students. A complete lesson plan for a teleoperated robot lab, vision processing lab, and advanced vision processing is found here - http://agents.sci.brooklyn.cuny.edu/robotics.edu/bcsoftware.php.

(Posted Sun, 04 May 2008 11:22)

RoboBrain - new console on Mac OS/X for SRV-1 Blackfin - 04 May 2008

Voxatec (Switzerland) has created a very nice SRV-1 Blackfin console for Mac users which provides a virtual joystick, real-time video display, C program editor and C program upload. It is available both as an application bundle as well as an open source X-Code project. This a very nice interface that's optimized for Mac users, and the developer has plans for further feature extensions. Make certain to visit the RoboBrain website - www.voxatec.com

(Posted Sun, 04 May 2008 10:46)

Mobot '08 at CMU - congrats to John Palmisano and Pikachu - 20 Apr 2008

At the 14th Annual Mobot Race, hosted this past week by School of Computer Science of Carnegie Mellon University, Society of Robots founder John Palmisano used the SRV-1 Blackfin camera with his ERP (Experimental Robot Platform) to win 2nd place overall and gain a Judge's Choice Prize for most innovative design.

Details of the design are found here - ERP (Experimental Robot Platform).
(Posted Sun, 20 Apr 2008 12:40)

exposure control for the OV9655 camera module - 13 Apr 2008

After deriving a stable set of register settings for the OV9655 camera module last fall, there hasn't been much done with the settings except for addition of a command to invert the image orientation. It has seemed that the "shutter speed" as well as gain control are a bit slow, so I started to tweak some registers today and got some encouraging results.

The formula provided by Omnivision for exposure time calculation is as follows:

Exposure time = 1/PCLK x 2 x 1520 x (Exposure line + Dummy line)
    Where
        PCLK => Pixel output clock
        Exposure line = (0xA1[5:0] x 1024) + (0x10[7:0] x 4) + 0x04[1:0]
        Dummy line = (0x2E[7:0] x 256) + Value of 0x2D[7:0]

The default settings are reg 0xA1 = 0x40, reg 0x10 = 0x40, reg 0x04 = 0x03. I experimented with reducing the value in the high order bits (reg 0xA1) from 0x40 to 0x20 to 0x10 and finally to 0x00. My guess is that there is a bounds checking in the firmware which sets a lower limit, as changing from 0x10 to 0x00 seemed to make no difference, but the change from 0x40 to 0x10 was noticeable, with reduced motion blurring and somewhat faster gain control response.

The register settings are found in ov9655.h in the data structure:
        static unsigned char ov9655_setup[] {};

As noted, the current default setting for register 0xA1 is 0x40. I would be interested in hearing from others who want to experiment with these settings. The next step is to look at the gain control registers - it appears that registers 0x13 and 0x14 provide significant control of that function.

By the way, the register definitions for the OV9655 are found here - http://www.surveyor.com/blackfin/OV9655-datasheet.pdf
(Posted Sun, 13 Apr 2008 14:33)

more robot Lisp ... - 12 Apr 2008

The basic motivation in adding Lisp to the SRV-1 firmware is to create a mechanism by which the robot processors could build adaptive world models and reason their way through that world. Our first attempt to integrate Lisp into the Blackfin firmware didn't go so well, though it exposed several problems - limits to the code size supported by the version of ldr-utils we use to build the .ldr firmware images, issues with the old Blackfin toolchain we were using and recommending (2006R2_RC6), and limits to extensibility as well as memory issues with the lithp code itself.

After a long week of head-pounding, these issues seem to have been resolved - we have a new version of ldr-utils for Linux and Windows, we have successfully switched over to the 2008R1_RC8 version of the Blackfin toolchain, and another Lisp interpreter which may prove adequate for our near-term requirements has been integrated into firmware.

Specifically, this version of Lisp was created by Dr Gregory Chaitin of IBM Research to develop proofs for theorems in set theory. It was originally written in Mathematica and then converted to C. Though not aligned with any particular Lisp dialect, it is compact, fast, and easy to use. Descriptions of the code are found here -

http://www.umcs.maine.edu/~chaitin/lisp.html
http://www.umcs.maine.edu/~chaitin/rov.html (sample code at bottom of page)

The interpreter in the latest firmware has not yet been connected to SRV-1 robot functions (other than memory and console), but robot functions will be added in the coming week, and stack monitoring as well garbage collection are planned. The interpreter can run programs from the flash buffer or operate interactively. The interactive mode is interesting, as we can configure the interpreter to load Lisp libraries from flash and then operate as the robot command processor. One thought is to add a natural language capability to the command interface.

This experiment is just in its earliest stages, and we may discover that the Chaitin Lisp is similarly too limiting, requiring that we consider an Lisp implementation more fully defined such as PicoLisp or TinyScheme. For the moment, however, this seems like a reasonable starting point.
(Posted Sat, 12 Apr 2008 13:00)

Just added a small Lisp interpreter to SRV-1 Blackfin firmware - 02 Apr 2008

I have been exploring some alternatives to the C interpreter currently built into the SRV-1 Blackfin firmware as our onboard behavior scripting engine, and came across a very compact LISP interpreter called Lithp, written by Scott Anderson. Tucked into the SRV-1 firmware, the code takes just a bit more the 6 kbytes of program space, and while it hosts only a fairly limited subset of Common Lisp, the code is very clean and easy to extend, and it already has a lot of capability.

The code is described here -

        http://www.umlautllama.com/projects/lithp/

and full documentation is found here -

        http://www.umlautllama.com/projects/lithp/lithp.pdf

The interpreter runs a program that has been transferred to the onboard flash buffer either from flash memory, via XMODEM transfer, or directly entered through the onboard line editor. The 'P' command launches code execution. The SRV-1 firmware has now been split in to separate versions to support either the C interpreter or Lisp interpreter, but not both in the same image. The download link for the test version of firmware is found in this forum thread -

        http://www.surveyor.com/cgi-bin/yabb2/YaBB.pl?num=1207001321

To get this to run, some new memory management functions were added and the processor stack was moved. We are just at the beginning of the testing cycle, so some revisions should be expected. Also, none of the core motor, sensor or vision functions have been linked to Lisp calls, though that should follow shortly. One of the goals is to link Lisp functions to the neural net library now built into the firmware - some interesting possibilities for SRV-1 behavior development should emerge once we figure out how to tie those pieces together.
(Posted Wed, 02 Apr 2008 16:02)

2.5Mbps test firmware for Matchport & SRV-1 Blackfin - 31 Mar 2008

We have test build of firmware from Lantronix which enables us to run the SRV-1 Blackfin with the Matchport at 2.5Mbps. This is a special build that is available only to SRV-1 users, and all support for this version of firmware needs to go through Surveyor, not Lantronix.

Configuration instructions are found here -

http://www.surveyor.com/cgi-bin/yabb2/YaBB.pl?num=1207001321
(Posted Mon, 31 Mar 2008 18:15)

3.6mm f2.0 lens is now standard with SRV-1 Blackfin camera - 25 Mar 2008

We have made a small change in the standard configuration of the SRV-1 Blackfin camera board. The standard lens is now the 3.6mm f2.0 previously offered as an option, replacing the 6.3mm f3.2 lens that originally shipped. The 3.6mm is a very nice lens, with much better light gathering than the 6.3mm.

We are still offering the 2.2mm f2.5 wide angle lens as an option, combined with a right angle adapter to lay the OV9655 camera module parallel to the Blackfin processor card.

(Posted Tue, 25 Mar 2008 00:40)

YARB 1.0 web page; perhaps some blimp kits in the future - 23 Mar 2008

To chart our robotic blimp development, there's now a web page devoted to YARB 1.0 (and successors), which includes some links to other interesting blimp sites.

http://www.surveyor.com/YARB.html

There has been a fair amount of interest in this project, so we are starting to give some thought to offering a blimp kit to SRV-1 users. While we will continue to provide complete DIY information for low cost solutions, our current concept is to standardize on a somewhat higher-end platform with brushless motors and shrouds for the propellors. We're talking with a few potential suppliers, and will post additional info when available. Please send an email to support@surveyor.com if you have an active interest in this project.
(Posted Sun, 23 Mar 2008 22:28)

robotic blimp (YARB 1.0) update - sensors added - 17 Mar 2008

The blimp now have some additional sensors - a pair of Maxbotics EZ0 ultrasonic ranging modules and a Honeywell HMC6532 I2C compass. Also, the camera module now points downward about 30-degrees via a simple extender. The camera angle is pretty good now - the wide angle lens has a field-of-view of approx 120-degrees, so the bottom of the frame captures the scenary almost directly below.

At the moment, the sensor data is unfiltered, which allows us to get an idea of how much variation there might be. The ultrasonic data is pretty solid - the forward looking readings bounce around a bit, but the download readings are fairly consistent. However, I think we will change to a narrower beam module - probably the EZ1. Also, it would be nice to have a couple of side-looking modules to enable some degree of mapping capability.

The compass is less consistent, and it turns out that we're getting magnetic field interference from the motors when they are running. At the time I recorded the video clip below, I wasn't paying attention to the readings, but subsequent tests show that the readings are varying by as much as 15-degrees when the motors are powered. Either we will have to move the compass, or add some compensation in software.

Here's a snapshot of the gondola with the additional sensors -

The plan is to make changes in the sensors to clean up the data, and then to write a script using the onboard C interpreter to let the blimp wander around on its own, perhaps following a course based on heading. After that, we will add some logic to use the camera to lock onto an object and follow it around while maintaining altitude and avoiding collision - that will be a bit more challenging.

Here's some video captured from yesterday's test session. The caption overlay shows heading, forward distance and height above ground in inches.

(Posted Mon, 17 Mar 2008 21:35)

YARB 1.0 (Yet Another Robotic Blimp) - first untethered flight - 13 Mar 2008

In my never-ending quest to defy gravity with the SRV-1 Blackfin, I installed the camera board and radio on a 66-inch helium blimp (ordered without their motor controller for a $100 savings) - interfacing the H-bridge on the SRV-1 combo radio/motor board directly to the two prop motors and one of the Blackfin's timer channels to the servo which vectors the prop thrust.

Here's SRV1Console with some different buttons that control the vectoring of the props and invert the video (the Blackfin board is suspended upside-down from the blimp gondola).

Using SRV1Console's archiving feature, I captured the video feed while piloting the blimp around the hallway and front room from my office. The blimp is surprisingly easy to pilot - this was my first attempt, and I didn't break anything, though there were some close encounters. The camera's a bit out of focus in the following video and the afternoon light washes out the scene somewhat, but you get the general idea.

Next step is to add ultrasonic sensors and a compass in order to start programming some autonomous exploration. This promises to be a very interesting project.
(Posted Thu, 13 Mar 2008 20:01)

new test version of SRV-1 Blackfin firmware - 05 Mar 2008

A new test build of firmware has been posted, as discussed on the robot forum -

http://www.surveyor.com/cgi-bin/yabb2/YaBB.pl?num=1204750102

and posted to SVN at

https://ssl.untyped.com/svn/repos/surveyor.com/srv-blackfin/trunk/SRV/

The following changes/additions to srv-blackfin-022608 are included in this test version -

added 'iR' command to read two bytes from i2c device ('ir' command only reads single byte). corresponding C-func is readi2c2();
added silent_console flag to disable console output during execution of interpreted C programs
changed C-func blob() to retrieve multiple blobs - blob(colorbin#, blob#). first call to blob(color, 0) will trigger new blob search, with blobs sorted by size. cnt = blob(color, 1) will retrieve the 2nd largest blob, etc.
added C-func imgrcap() to capture a reference frame and imgdiff() to compute difference between reference frame and current frame
added bp.c backprop neural net library, but haven't connected it to any inputs or outputs yet

Also, there are some new file transfer scripts for srv1.ldr and C-test.c - take a look at send-ldr.sh and send-c.sh, but make certain to change IP addresses before using these. I believe that lsz be used interchangeably with sx. By the way, if anyone knows of Windows versions of sx or lsz, please let us know.
(Posted Wed, 05 Mar 2008 17:21)

another fun SRV-1 Blackfin firmware extension - real-time frame differencing - 26 Feb 2008

Just added a couple of functions for storing a reference frame and differencing that reference frame against the most recently captured frame. This will be useful for laser range finding, by comparing frames with and without the lasers on, and it will also be quite useful for motion detection.

Here's an example frame sequence:

#1 - normal capture

#2 - normal capture with lasers on

#3 - reference frame captured with lasers off, frame difference shown

#4 - lasers now on, frame difference shown

Here's a motion detection example:

#5 - normal view before capturing reference frame

#6 - differencing enabled, no motion

#7 - differencing enabled, motion detected

More details on this test version of SRV-1 Blackfin firmware are found on the Surveyor Robotics Forum and code is posted to our SVN repository
(Posted Tue, 26 Feb 2008 16:21)

SRV1Console java source code posted - 21 Feb 2008

SRV1Console.java can now be downloaded from

http://www.surveyor.com/blackfin/

To compile -

javac -classpath .:ImageButton:RXTXcomm.jar:wstreamd_embed.jar: SRV1Console.java

Please note that this code is GPL open source, so modifications and extensions are meant to be shared.
(Posted Thu, 21 Feb 2008 12:32)

Test firmware; revised (simplified) bundling of SRV-1 Blackfin board set - 20 Feb 2008

In response to user requests, we have recently added a number of features to the SRV-1 firmware, including a failsafe mode as well as support for servos and electronic speed controllers, ultrasonic ranging modules, accelerometers, and I2C devices, as discussed here on the robot forum. While the firmware is available for testing, it hasn't yet been formally released, as a few image processing functions still need to be added, but this is expected to wrap up by the end of the month.

Many of the firmware requests are coming from users who are building their own motorized robot bases or UAVs, and we are finding an increasing number of users want the SRV-1 Blackfin board set without the motorized base. We are glad to see this trend, and to accommodate this, we have reorganized our SRV-1 board bundle to include all of the electronics of the SRV-1 robot except for the battery and motorized base, i.e. the SRV-1 Blackfin Camera board (500MHz BF537 Blackfin and OV9655 1.3Mpix camera), combo radio/motor board, Lantronix Matchport WiFi module, antenna, and 2 laser pointers.

A complete description of the bundle is found here.
(Posted Wed, 20 Feb 2008 10:25)