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The Earth Explorer Project


A slight diversion

I took my robot down to my dad's house on one of my trips. I was bored and I sat there looking at my robot base which is made out of go-cart parts. I was also thinking about my 2-cycle engine... Hey! I could build a go-cart!

So the base and the alternator test bed got disassembled for this new project. I won't go into the details, but the results were very painful. But the outcome was that the base was not in one single piece anymore.


A call to arms

We had a message on the TCRobots list server stating that the MISFITS science fiction group wanted us to bring our robots over to show them off. I had to reassemble the Earth Explorer in order to demo anything. So I started rebuilding it and decided to make some improvements as I went. I needed to move the motors over to make room for the encoders. When I did, the reduction shafts weren't long enough. So I made some new ones that extended almost to the center of the body. I added a support block in the center which supported the inboard end of each shaft. I ended up with three bearings on each shaft when I only wanted two. That is because if I only used two, there was nothing to hold them in. So I left both original bearings and added the third.

I also noticed the conduit clamps which held the axles on were very bent up. That is because they were taking alot of force since everybody insists on riding on the thing. So I took Gary Croll's suggestion and used 1/4" "U" bolts to hold the axles. Eventually I need to add some kind of chain tightener, but that is for some day when I am bored.

So I transported the Earth Explorer and Research 2 robot down to the meeting and showed them off. Rand also took his sumo robots and gave a talk on them.

There are some pictures from the MISFITS meeting in the August 2000 meeting pictures.


This is how it looked after it was reassembled.


Enough is enough

I think it got disassembled for another go-cart experiment, but I won't go into that. I decided I needed to paint this thing. So I took it all apart. I also decided to fix a few things while it was apart. I finally got around to filing flat spots on my shafts like Alan and Brynn kept telling me to do. That solved two problems. First, it helps prevent the sprockets from slipping on the shafts. Second, it keeps the shaft from getting messed up from the set screws. This means I can actually get the sprockets off without pounding on them.

I decided to paint the outside yellow. I like yellow. I decided to paint the inside black, just for contrast. Turns out I should have painted both the inside and outside the same color. It would have saved me about an hour of masking with masking tape and newspaper. I also painted the motors while I was at it. They look brand new. They were starting to rust before.


It looks much better after the paint job.


Rest of the body

I needed to finish the body. So I made a top box. I thought about just bolting it down. But I figured it would be handy if it were hinged on the back or one side for easy access. I made the box the same size as the lower box, just to be symmetrical.

Oh, I forgot to mention that I bought some new batteries. I was using 12V 7AHr batteries. I built the bottom box to accommodate their size. That way the top was completely flat so I would have various options for adding a top. But I found some 12V 17AHr batteries for $9.99 at Northern. I couldn't resist so I bought two. Unfortunately they are taller than my box, by about an inch. But I am going to use them anyway.

So I made the top and bolted on a big piano hinge I found at Axman. I made battery boxes to keep the batteries from bouncing around. I was going to bolt the electronics inside the upper box but I decided it would be hard to work on them in such a confined space. So I made a panel that lays across the bottom box. I also hinged this panel for easy access to the drive train.


The new pieces before painting.


Assembled robot with the electronics panel down.
You can see the batteries protrude through the panel.


Assembled robot with the electronics panel up.
You can see the battery boxes and the DC/DC converters.


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