The Caterpillar (production prototype)
@ May 15, 2009
- Actuators / output devices: 8 minature servos, 4x 3mm LEDs. Bi-colour LEDs on antenna
- Control method: Autonomous and IR remote. Optional serial input for Xbee
- CPU: Picaxe or Atmega 8.
- Power source: 4x AAA NiMh 800mAH.
- Programming language: Picaxe basic or C depending on processor
- Sensors / input devices: Antenna, tilt switches, IR reciever. Optional IR or sonar range finding.
- Target environment: easy terrain
| Attachment | Size |
|---|---|
| Caterpillar_Main_Board_Schematic.jpg | 542.03 KB |
| Caterpillar_sensor_boards.jpg | 908.67 KB |
| CATERPILLAR_China.BAS | 3.97 KB |
Caterpillar Evolution video shows how this project has gone from a simple hobby robot to a mass produced robot. The first clear ABS caterpillar is now up to mischief in China :D
Update 3 of July 2009
Well the first prototypes came out of the factory and of course some calibration is always required. DAGU contacted me to say they had a problem. It seems the program needs calibration to work with the new roll sensor as resistors can vary slightly even when they are all marked as the same value. Consequently the caterpillar constanly thinks it has fallen over and needs to get back up. The end result is quite funny :D
Whoops!, my mistake :0
I specified a different analog input in the schematic to what was being used in the program.It's all fixed now :D
I have posted some pictures if the new circuit boards used. The Antenna now use springs where I had wire, this is a big improvement as occasionally the wire got bent when stuck in a corner or getting back up on it's feet. Once the wire was bent it kept thinking it had hit something.
The IR sensor has been moved to the top of the roll sensor board so that it can recieve IR better.
@ Sun, 2009-07-05 00:19
nice design
@ Sat, 2009-07-04 15:38
Wow!
@ Sat, 2009-07-04 16:01
To be honest
@ Fri, 2009-07-03 19:19
Realistic.
Simply gorgeous. In the first video the caterpillar seems like a poisoned animal... its not very funny because the scene is quite realistic. In the last one the caterpillar work very good, it has realistic movements. I'm wondering which sensor(s) you use to verify if the bot is "standing" or if its lying on side.
Congratulations
@ Sat, 2009-07-04 00:56
roll sensors
Nothing expensive or fancy. The roll sensors are just 2 mercury switches set up in a voltage divider circuit to give an analog output. I'll post pictures of the boards and a schematic.
@ Fri, 2009-07-03 09:01
Funny!! Could program it as
Funny!!
Could program it as tamagotchi, where one variable was "Feed it with wine" :D
@ Fri, 2009-07-03 12:34
that could be easily done
@ Fri, 2009-07-03 08:44
LOL!
@ Fri, 2009-07-03 09:00
I was impressed
Sure I programmed it to get on it's feet, I didn't know it was capable of completely rolling over :P
It reminds me of a caterpillar being attacked by ants.
@ Sat, 2009-05-16 22:07
Congratulations OddBot!
Congratulations OddBot!
Looks really good, the antennas with the leds are great and the way the bot gets up after falling is awesome!!
I'm sure I will build one as soon as the kit is released!! ;-)
@ Sat, 2009-05-16 17:18
Curling Body
Wow - well impressed with the Fine-tuning - he is running (or is that "inch-ing" ) much faster and with real confidence.
The Curl-up response when pushed over gives perfect catapillar "stress" reaction - Super.......
@ Sat, 2009-05-16 17:27
Honestly
Although many of the moves look like they are an imatation of an animal such as the curl response it is actually a case of function following form. The body can only move so many ways and only so many moves will gain the apropriate response.
@ Fri, 2009-05-15 22:39
Congrats, next i hope to see
@ Sat, 2009-05-16 01:09
Junior... umm... er...
@ Fri, 2009-05-15 21:44
I kinda like it in orange!
@ Sat, 2009-05-16 01:05
Colour
@ Sat, 2009-05-16 11:02
Uh!
@ Fri, 2009-05-15 14:21
Well done. Good job
Well done. Good job.
BTW: In precaution I have downloaded all your schematics before Arexx NL declares it as confidential ;-).
@ Fri, 2009-05-15 15:17
Ha Ha
@ Fri, 2009-05-15 13:31
Absolutely brilliant!!I have
Absolutely brilliant!!
I have no other words!
@ Fri, 2009-05-15 13:46
High praise indeed :D
@ Fri, 2009-05-15 13:17
Great antennaeaeaaaaeeas!
I love the dual colour LEDs all around. And how they indicate what it's sensing or doing.
The tail antenna seems to be missing from the pictures. Or is it way smaller than the ones on the head?
How do you light up the LEDs on the side? Did you really run all those extra wires from the main board, or are they hooked to the servo line? Somehow.
And what would be a great, mercury-less, cheap, replacement for those tilt sensors?
@ Fri, 2009-05-15 13:37
LEDs n stuff
The LEDs on the body are driven by bits 4-7 of port C. They are single colour 3mm LEDs. The body has moulded sockets for 3mm LEDs in the body segments including holes for the leads.
The dual colour LEDs on the antenna are operated by the antenna. The green segment is wired directly to power. When the antena hit something the red segment is switched in parallel to the green segment. Because the red segment has a lower forward voltage than the green segment (typically 2.1V for red and 2.4 for geen) it drops the voltage across the green LED below it's opperating voltage causing it to turn off.
I haven't made the tail antenna yet, I am going to try a slightly different design because I want it shorter. It could even be replaced with an Amander LDR setup or my IR obstacle detector. It is not critical, just a way of telling the robot if it backed into something or being attacked from behind.
I would like to get a couple doing a sumo style battle... BATTLEPEDES or SUMOPILLARS :D
@ Fri, 2009-05-15 21:38
Interesting sensors
I did not realize your antenna were actually sensors to the brain. How cool. Walk through!
At first, I thought the ring around the wire in the diagram, was indicating some sort of shielding. It is in fact a switch. I did not recognise it in the hi-res photo. Would you describe the mechanics of the switch? Or publish a close up photo?
Or a walk through!
BTW: clever use of datasheet knowledge! Different forward voltages.... wow. Walk through!
@ Sat, 2009-05-16 01:20
Ok, ok already
@ Fri, 2009-05-15 09:44
your bugs are great
your bugs are great oddbot...
respect !
@ Fri, 2009-05-15 10:25
Respect to you too
@ Fri, 2009-05-15 09:47
That's just great...
@ Fri, 2009-05-15 08:27
Congratulations
@ Fri, 2009-05-15 08:32
Thankyou
I hope we will see edward on the shelves one day :)
@ Fri, 2009-05-15 09:40
I received some questions
@ Fri, 2009-05-15 10:30
I understand
@ Fri, 2009-05-15 07:16
Wow Oddbot !That's great!
Wow Oddbot !
That's great! I like the led's and the self-righting is awesome too.
Your my hero! Well, this and the sunscreen for thermal paste was the clincher.
Forgive my nosey-ness, but do you get some profit for each of these sold by Dagu? The idea of making this into a career is just too tempting !
@ Fri, 2009-05-15 08:24
Nosey Bugger! :P
Yes :p
My advice is to buy a Mr. Basic and show him how good you are in the competition if you haven't got anything else to demonstrate.
@ Fri, 2009-05-15 06:53
Dude that is too cute! Fun