Sixth Sense GarffitiBot - First Dry Run - Blog17

23 Mar 2019

This is a big day - the GraffitiBot made its maiden voyage!

This was just the first attempt at programming an autonomous route that would test the steering and the main drive.

It is literally a dry run, there are no pumps or even reservoir on board.

I could spend some time to make it look more impressive and get some better camera angles, but I need to start working on the hydraulics - the nozzles need a lot of work, not to mention the software.

Getting this far has taken a lot of work, but see it run is what is all about.

Relevant Links

Sixth Sense Design Challenge: About This Challenge

Sixth Sense Design Challenge: Technical Documents

Sixth Sense Design Challenge

KMT32B Magnetic Angle Sensor

GraffitiBot Project Blogs

Sixth Sense GraffitiBot - blog 1

Sixth Sense - Kit Unboxing and Other Parts - GraffitiBot blog 2

Sixth Sense - Sensor Circuits - GraffitiBot blog 3

Sixth Sense - Interfaces - GraffitiBot blog 4

Sixth Sense GraffitiBot - System Interconnect - blog 5

Sixth Sense GraffitiBot - Wheels & Motors - blog 6

Sixth Sense GraffitiBot - ST Sensor Tile App - blog 7

Sixth Sense - Load Cell PCB - GraffitiBot blog 8

Sixth Sense - Magnetic Angle Sensor - GraffitiBot - Blog 9

Sixth Sense - LCD Interface - GraffitiBot - blog 10

Sixth Sense - Pump Controller - GraffitiBot Blog 11

Sixth Sense Main Drive Motor - GraffitiBot - blog 12

Sixth Sense Motor Controller Mods - GraffitiBot blog 13

Sixth Sense - RTD - GraffitiBot Blog 14

Sixth Sense Mechanical Design - GraffitiBot Blog 15

Sixth Sense GraffitiBot Motor Wiring - Blog 16

Sixthe Sense GarffitiBot - First Dry Run - Blog17

Sixth Sense GraffitiBot Hydraulics - Blog 18

Sixth Sense GraffitiBot Printing Graffiti - Blog 19

Sixth Sense GraffitiBot - Summary - Blog 20

Top Comments

jw0752 over 3 years ago in reply to dougw

Hi Doug,
If you can decrease the ID of the hose you are using the increased flow rate might purge the bubbles.

John
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shabaz over 3 years ago

Hi Doug,

This is looking great! Good luck with the hydraulics!
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14rhb over 3 years ago in reply to dougw

That comment was so funny
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dougw over 3 years ago in reply to jw0752

That is a good idea.
My biggest problem is purging the air from the lines and keeping it out.
The nozzles restrict flow enough that air bubbles aren't forced through the hose very well.
Air also defeats any siphon as well, but when air is properly purged, the siphon effect is not very apparent.
There are several other more pressing problems.
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jw0752 over 3 years ago

Hi Doug,
If you haven't already considered this you might want to use a duckbill check valve on your jets. They provide a slight back pressure so that there is less chance of a gravity siphon. Here are some that are used on the oil lines of a chain saw.

https://www.ebay.com/i/253803363604?chn=ps

John
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