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Holonomic in the Hizzouse

Partially assembled top view
Partially assembled view from above

I’ve spent months planning my next CATPOO and it’s all printed out. All requisite parts are either here or on their way in the mail.

Highlights include:

  • Omnidirectional wheels for holonomic goodness
  • Infrared night vision camera
  • 16x High intensity IR LEDs
  • 7″ LCD with touchscreen
  • External USB and network ports
  • Wireless AP support
  • Rear motion sensor for Spidey Sense
  • Forward and rear proximity sensors
Front view showing IR LEDs and camera
Front view showing IR LEDs and camera

Once I get the few minor parts remaining from Pololu, I’ll be ready done with the building in a day. If you think you might need it, and it’s only a $1 or $2, just get it. Waiting three days to finish the build because I’m short on 1″ #4 screws is a terrible experience.

Once built, I’m nervous when it comes to figuring out how to coordinate all four servos to move in a straight line. Previously, I ran into trouble with getting the forward and reverse speeds to be equal. It could also be related to the servos I’m using. I plan to isolate whether it’s my fault, the motors’ faults, or a combination of both. I’ll have eight servos soon.

If I can’t get four functional servos out of that, I’m smashing the servo controller I have a sledgehammer and switching to stepper motors. I didn’t want to spend the money or effort, but it’s looking like that’s the direction I’ll be going.

It’s Alive!

Finally! After over a year off and on, I finally have all the parts and necessary free time available.

Milestone Highlights

  • The basic robot is now working with the two servos to maneuver with
  • The night vision camera is working (at about half the full brightness)
  • Video lag to web UI on a smartphone is less than one second in bright areas, twice as long in dark (due to exposure times delaying transmitting next frame)

Next Up

  • Add in more sensors (highest priority is the proximity sensor for the front)
  • 5″ LCD screen for the top for debugging and status output
  • Integrate the momentary switches with built-in LEDs to perform operations (ex: reset networking, turn on/off IR lights, etc.)