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---++ GPS & Wifi Mods to R118

Robot 118 is a P3-AT equipped with Gyro, TCM2, DPPU PT unit, and Bumblebee stereohead.

Robot 118 was modified to carry a GPS on a tripod mounted to the top-plate. This gave the GPS sufficient hight to get a very reliable signal. The GPS was connected to ttyS3 (com port 4). Note that Com port 4 needs to be initialized to use IRQ 5 before it can be used.

The extra payload mounting opportunities offered by the tripod were exploited to move the WiFi AP from the top-plate onto the tripod body, for a less crowded top-plate and probably better WiFi range.

These modifications to Robot 118 were tested using an modified stereoServer/clientDemo that stores GPS and TCM2 data in addition to the odometry and stereodataset file information.
---++ Tripod

The Tripod is an aluminum light stand with telescoping center column and legs. The leg ring is pushed down as far as possible to create a space under the tripod and elevate the center column. The legs are mounted as follows: one centered on the back rim of the top-plate and one on each side of the top-plate. This leaves the front clear for the DPPU to rotate the stereocamera unobstructed. Holes were drilled into the top-plate and angle brackets used to anchor the tripod legs. Only the mid-back hole required that the top-plate be opened. The electronics were covered during this last operation to prevent any drillings from fouling up the works.

A ferrule mounted to a horizontal plate was used to secure the GPS to the top of the center column. The horizontal plate was secured to 2 of the 4 moutning holes under the GPS. The height of the GPS was about 5 foot and was selected somewhat arbitrarily.

The Wifi AP was secured to the center column about half way up using cable ties.

   * Base of the Tripod achored to top-plate

<br /><img width="576" alt="R118-mod3.jpg" src="%ATTACHURLPATH%/R118-mod3.jpg" height="482" /> <img width="602" alt="R118-mod2.jpg" src="%ATTACHURLPATH%/R118-mod2.jpg" height="480" />

   * Complete system and closeup of Tripod

<br /><img width="329" alt="R118-mod1.jpg" src="%ATTACHURLPATH%/R118-mod1.jpg" height="934" /> <img width="325" alt="R118-mod4.jpg" src="%ATTACHURLPATH%/R118-mod4.jpg" height="933" />

---++ Software

The GPS was tested using the serialGPS object. The source files for this homegrown GPS interface are serialGPS.cpp/.h.

See the software section for more details on this.

-- Main.DamianLyons - 2011-07-11

Attachments

Topic attachments
I	Attachment	History	Action	Size	Date	Who
jpg	R118-mod1.jpg	r2 r1	manage	68.7 K	2011-07-11 - 18:44	DamianLyons
jpg	R118-mod2.jpg	r2 r1	manage	151.9 K	2011-07-11 - 18:44	DamianLyons
jpg	R118-mod3.jpg	r2 r1	manage	151.5 K	2011-07-11 - 18:43	DamianLyons
jpg	R118-mod4.jpg	r2 r1	manage	52.6 K	2011-07-11 - 18:45	DamianLyons

Topic revision: r1 - 2011-07-11 - DamianLyons