Ajax Harbinger of the Robot Apocalypse

Let's Make Robots Robots
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Ajax is my first robot, he is based on the LMR "start here robot" with a few extra features. Ajax is 32 centimeters tall and about 1 kilogram in weight. His body is made of MDF (dense cardboard) and his head is the cap from a spray paint can. POWER: 4 AA NiMH batteries. DRIVE: 2 GM9 geared motors. MICROCONTROLLER: PICAXE 28X1 PROGRAMMED: PICAXE Basic SERVOS: 3, one for his head and one for each arm. SENSOR: SHARP IR range finder. CONTROL: IR remote control sensor. SOUND: Piezo speaker. BLING: Four LEDs, based on the tech tip from TomPhysics. Ajax can perform 6 functions they are: STOP - Do nothing. BIT - Built In Test, moves around and waves its arms and head to show it is up and running. DRIVE - Can be driven around using the remote control like a toy car. GUARD - Scans an area saving range measurements to memory and then alerts if any of the ranges change. WANDER - Move around at random, trying not to bump into anything. SING - Play one of the four tunes that are built in to the PICAXE 28X1. Ajax has been a lot of fun to build and program, I am looking forward to building my second robot soon. Attached as a file below is Ajax's source code, it should be readable in any plain-text editor.

Wanders around without bumping into walls, guards small area, sings.

  • Actuators / output devices: 2 GM9 motors and 3 servos
  • Control method: IR TV remote control
  • CPU: Picaxe 28x1
  • Operating system: Picaxe basic
  • Power source: 4 AA NiMH
  • Programming language: Picaxe basic
  • Sensors / input devices: SHARP IR sensor, IR remote control sensor
  • Target environment: indoors
This is a companion discussion topic for the original entry at https://community.robotshop.com/robots/show/ajax-harbinger-of-the-robot-apocalypse
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Plenty of character to this build

There’s some interesting ideas for the rest of us who want to build something a bit beyond a SHR. Perhaps you should add some cliff detection sensors to save him falling off the desk. Nice build and good to see you again after a break. I think this explains why we haven’t seen you for a bit.

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Hey Merser

Hi Merser, great to see you again.  Ajax was just full of “lessons” before I was done with him.  His IR sensor is mounted too high and so he can ‘trip’ over low objects like some chair legs.  Also he detects obstacles to one side much more quickly than on the other.  There was a good tech tip here somewhere that warned of that.  While its cute to mount the sensor horizontally to look like eyes, you are probably better off mounting it in the vertical position.  My current intention on robot #2 is to mount two IR sensors in servos low on the base and angle them down.  They will scan as the robot rolls forward and look for …low obstacles and edges.  I will use IR sensors and sonics at middle and head to try and get a robot that can miss most of the furniture.  I am still catching back up on my LMR reading, looking forward to reading your posts.

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Ajax

Nice presentation!  I like Ajax!