walking robots, SumoBot, and other fun stuff.

So, I wanted some way to be certain that all of the parts from the radio control system stayed together and nothing got damaged or tangled etc.

I looked on the internet for any project I could find involving two servos.

The first thing I found was this walking robot on Instructables:
"http://www.instructables.com/id/A-Servo-based-4-legged-Walker/

This walker uses a micro processor to control it and therefor simply walks forward at a set pace. Since I don't have the Adruino processor, I used the radio system in it's place, hoping that I would be able to control the thing "by hand." As it turns out, it was extremely simple to control. Move one stick on the controller all the way in any direction and then rotate the stick in a counterclockwise direction around it's limits, and the thing will walk forward. Rotate the stick clockwise and it will walk in reverse.

I will add a video once I get it off the camcorder.

I played with that for a while but got quickly bored with it, and decided I wanted to investigate the continuous rotation mod for servos...

Here is a tutorial:
http://www.instructables.com/id/How-to-modify-a-servo-motor-for-continuous-rotatio/

As it turns out, modifying the two servos that I have was not as difficult. I did not have to glue any gears together and I did not have to cut the top off the pot (double click 'potentiometer' for a definition). All I had to do was sand off the 180 degree stop tab and slip a piece of plastic out of the output shaft.

Now that I had two continuous rotation servos and a complete radio control system, I simply HAD to build a crude, two-wheeled sumobot.

I will add a video once I get it off the camcorder.

It worked but I wanted to try different things so I destroyed it and started over several times. I have used several different wheels including some MASSIVE washers, wheels off a child's toy, and considered CDs.

I think the next step will be a much wider base with CDs for wheels and the entire body of the 'bot hanging beneath the 'axle', devoid of a third wheel.

I will keep you posted.

Mike from DC.

Turkey Day

No, not my birthday, that's the wrong turkey!

Just wanted to wish those few people who actually watch my blog:

HAVE A VERY WONDERFUL THANKSGIVING!!

Michael and Christina, from DieCastoms!

Magum Opus has a radio!

Two things..

First, a friend referred to my project as my "Magnum Opus" the other day. It means one's "greatest achievement." I thought it sounded really cool so I think I might letter it on my truck. It will be in red fancy lettering, looking like a signature or autograph, under the window on the driver's door. "S. Christopher" will be in the same place on the passangers door, that way I will always be traveling with "Saint Christopher," the Patron Saint of Travelers at my side.

The other thing is..
I HAVE R/C NOW!

Dad brought home an old Futaba airplane transmitter and receiver, servos, battery packs, and a charger. For those of you who may know something about the equipment, here are the specs:

Transmitter (Tx)
FP-T4NBL "Attack 4"
4 Channel, 72.630MHz (channel 42)

Battery Pack (Tx)
Futaba NT-8JY
9.6VDC - 500mAh

Reciever (Rx)
Futaba FP-R114h
4 channel digital proportional, 72.630MHz

Battery Pack (Reciever)
Futaba NR-4J
4.8vdc - 500mAh

Charger
Futaba FBC-8B(4)
9.6VDC - 50mAh (Tx)
4.8VDC - 50mAh (Rx)

Servo
Futaba FP-S148

Servo
Aristo "Elite-1"
ARI-03-400

The system is currently set up for channel 42, 72.630MHz, which is for air use only and not legal to be used on land or sea vehicles. It will be fine for now for testing and whatnot but the channel WILL have to be changed before I can start making appearances with the truck. I SHOULD be able to just buy a pair of quartz crystals and plug them in to change the channel. That shouldn't cost much.

Either of the servos included will run the throttle, but neither are strong enough for much of anything else.

Long awaited videos of the truck engine running

Here are a few pieces of video I took about two weeks ago of the engine for the truck.

The engine is an X6 Pocket Bike engine. It is 49cc 2-stroke and is running on about an ounce of 40:1 two-stroke mixed fuel. The engine is being started with a set of "self contained jumper cables" or a "jumper pack" in some shots, and pull started in other shots.

Several times during the videos, I lift the engine off the ground and it promptly stalls.. This is because the fuel is gravity feed, thus the engine runs out of gas any time it is higher than the gas tank. In the final build, the gas tank will be mounted inside the top of the sleeper cab. This will provide the same gravity feed that was present in the motorcycle (X6 Pocket Bike) that the engine came out of originally.

In the video the exhaust port is open so you get the full sound of the 2-stroke, but with the muffler in place the engine is surprisingly muted and quiet. I have no clue if I will make any attempts at manipulating the sound or not. I was considering injecting motor oil or "smoke oil" into the exhaust to simulate a hard working diesel engine.

Hope you enjoy these videos!



By the way, the large silver item to the right of the engine is an 8:1 reduction "Constantly Variable Transmission" or CVT. It is from the pocket bike and houses the clutch. There is also another reduction between the secondary pulley and the chain sprocket output shaft. The total reduction is unknown at this time, but so is the engine's total RPM so I can't do any calculations anyway. The rear tire on the pocket bike is roughly the same diameter as the tires on the truck so I expect the same speed if nothing else is changed. For this reason, I want to add MORE reduction to the drive train to generate more pulling power and less overall speed. My target is a top speed of 15 miles per hour, and as much as it can possibly pull.

Here is another video:

OMG! SERIOUS SPONSOR!!!!!

I have just had an offer from an old friend to donate LABOR AND MATERIALS for a CUSTOM COMPLETE Fibreglass body for the truck!!!!

In exchange for his services, C will be getting his business name (of his choice) lettered on the cab doors!!!!

I will have to build the chassis and fit the engine and build a wooden form for him to glass over. He has offered to do opening doors as well. I will be doing all fitting work, but he will be making the cab itself.

This is one of the BIGGEST contributors to the truck to date!

I will write more on this post after C and I work out some more details.

Please note that those of you on the email list will NOT be notified of edits to posts, so always check the blog directly when you see that a post has been made. I have a nasty habit of posting and then editing.

THANKS C!

Mike from DC

SSSPROOIING!!!!

So I got this box... plain brown cardboard, not even large enough for a hard cover book... The Post Office stuck a tag over the return address so I have no clue who it is from.. Let's open it...

SSSPROOIING!!!!

I HAVE TRUCK SPRINGS!

Ok, ok, so I opened it three days ago and am just now getting around to posting. Hush.

I had no idea how stiff a 43# rate spring would be, but now that I have one, i can tell you that I can just barely compress it all the way in one bare hand. All 6 were in the box and all are identical. I may slightly redesign my suspension for their use, but they are almost perfect for my application.I think I whould have ordered them just a little longer, but I can deal with it.

Pictures to follow when I get around to taking some.

Mike from DC.

Live Help and IRC Chat rooms added to DieCastoms.BlogSpot.com!!

As a sort of experiment, I have added a Live Help!!!! function to DieCastoms. It only will work when I or my wife are logged into the system, but feel free to try it! We would love random chats from our visitors even if you aren't in need of assistance!! A permanent link to the Live Help!!!! feature can be found at the upper right of the page, below out logo.

We also have added an IRC channel to the BOTTOM of the page. This is a Java applet and has an expired security certificate. I am aware of that. I got the applet from a trustworthy friend, however, who has been using it for several years. It is safe.
For those of you who have other IRC clients that you would like to use, our room/channel is #DieCastoms and is on the server centralchat.net

We look forward to hearing more from our readers!

Thanks for visiting DieCastoms!

Mike, from DC.

Just a quick post,

the fan in my Toshiba Portege Laptop has crapped out. I cannot run the laptop WITHOUT the fan (because my wife won't let me), so posts here may be few and far between... as if that would be anything new...

Ah well. Them's the breaks.

Mike, from DC.