Brian's ROACH Page


RObotic Automation Control Hierarchy

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New Pictures

Here you can see the white camera, and conical lense hood of the IR pyroelectric sensor on the pan/tilt head. The pan (stepper)/tilt (servo) mechanism is partially obscured.

You can see the main power batteries arranged in a triangular configuration. The SRAM backup power is supplied by 4x1.2VDC NiCd batteries located in the center of the triangle. Video system power is supplied by a 12 volt battery pack on the underside of the robot.

At the rear of the robot are two BNC connectors. The one closest to the camera is for the video transmitter (not mounted yet), and the antenna mounted farther away from the camera is for the radio modem (currently mounted under the upper shell).


Latest News

The ROACH is rapidly nearing completion. All major structural areas have been finished. The locomotion, and pan/tilt interface are tested and working. The shaft of the stepper motor is directly bound to the sensor array which greatly limits phase stepping strength. This approach also adds an annoying overswing. I am considering replacing the stepper motor with a gear reduced DC motor, or stepper motor. 
Check out the ROACH's Software page


Status

1-1-98 The ROACH project has been completed. The information generated from ROACH research has allowed me to move on to bigger and more complex robotic systems such as the Mowbot, and Blue Cube. In retrospect, the robot base could have been better designed, and use lighter batteries to reduce motor current draw. The IR sensors used worked far better than expected, and will be considered for use in further projects (thanks MIL!) the 68HC11 is a great low-end micro, and is an excellent teaching tool for embedded systems when power conservation, and size are the most important factors. PS. The Proxim Proxlink board is still available from Timeline

4-4-97 I was having a few problems with the servo->sensor array linkage. The joint didn't appear to be strong enough to support the full weight of the sensor array, but I fixed it! I hacked apart an old printer to find a very specific part. It originally housed two gears that meshed together within a metal 'U'. Three hours of cutting and machining with my Dremel tool and it was in place. I can finally continue mounting the sensor array! I have decided to mount the sensor array to the pan-tilt mechanism with 'carpet tape' for safety reasons. After all, I don't want the entire thing to snap off if it hits something.


To Do

  • Do power/weight/component AH calculations
  • Permanently mount motor power cells to base.
  • Design, build docking station, connector mating system.
  • Purchase Dinsmore 1490 digital compass, mount on 6.270 board. 

  • Before 


    After

    Here you can clearly see the old weak servo/stepper link, and the secure, yet kludgely looking support fixture. It only looks bad, it's really quite strong.


    Favorite Related Links

  • Another robot named ROACH.
  • A real Robo-Roach!
  • Some confrencee's experiences/code for AAAI '93, pay special notice to the Subsumption code in Jeffrey Graham's experiences.
  • MIT's Cherupakha FTP site.
  • NASA's Inteligent Mechanism Group.
  • MONDOTronics web page
  • Brandeis University's Maja Mataric (formerly of MIT's Insect Lab) now has her own Robotic Interaction Lab.
  • A very informative Cognitive/Agent Architecture page at U-Mich.
  • A really cool Polypod robot locomation implimentation.
  • Tons of info on Ultrasonic position mapping.

  • Last update 3-16-1998

    Brian Rudy