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Remote Control Lawnmower

Posted: Wed Jul 14, 2004 5:47 am
by dburlesn
I added a short video of the prototype to the web page today.<p>http://www.stuartmperry.com/rc-mower/mower3.htm<p>I have already taken this version apart to add height control.<p>I also choose to relocate the motors, and batteries, and shorten the wheel base.
overall length is up however.<p>Any suggestions?<p>Thanks<p>David

Re: Remote Control Lawnmower

Posted: Wed Jul 14, 2004 7:13 am
by rosborne
Yes, bring it over to my house for a demo. ;)
-Rick

Re: Remote Control Lawnmower

Posted: Wed Jul 14, 2004 8:39 am
by myp71
Does it have a kill switch on the remote?So you can park it back inside the garage when done. :) <p>
~Ryan<p>[ July 14, 2004: Message edited by: My-P71 ]</p>

Re: Remote Control Lawnmower

Posted: Wed Jul 14, 2004 9:43 am
by jollyrgr
I have a couple suggestions just in case you did not include them. There should be a PULL HERE TO STOP flag or similar warning that kills the engine and electric motors. Thus if it gets away from you either because of electronics failure or some idiot with a different remote overriding your signal you can kill it instantly. <p>Did you include a fail safe so that if the remote signal stops the engines shut down? If I were building the unit I would include a "dead man" option so that total loss of signal causes the wheels to stop instantly and causes the mower blade to stop a couple seconds later.<p>If you plan on a different setup, I would make a couple changes to the overall design.<p>1.) Move the drive wheels to the front and put two castering wheels in the back instead of a single wheel. Add or reinstall the original handles so that you can tilt the front of the mower up should the wheels continue to run in a failure mode. Thus you can stop the mower from moving if it "runs away" and can move the mower around without using the remote.<p>2) Use the gasoline engine to drive the wheels instead of the electric motors. Use two belts, one with a twist for "reverse", and a idler pulley to switch between the two belts. Both belts would run "slack" and the drive axel would be solid. Move the idler pulley one direction to engage one belt, the other for the reverse direction. For steering, use a caster (or casters) that are "locked" to a shaft. Rotate the shaft(s) with a geared motor or chain drive. <p>3) There should also be a bumper on the front and back that when hit either reverses/stops the drive motors or kills the blades or both.<p>I'm not "dissing" your project, just throwing out ideas for a better or alternate design. I think your project is quite nice. If it were on the market, I'd consider buying one for my parents.

Re: Remote Control Lawnmower

Posted: Thu Jul 15, 2004 4:11 am
by Mike
Those little things are cool!! I saw a little Toro one cutting somebodies grass at some house we drove by.

Re: Remote Control Lawnmower

Posted: Thu Jul 15, 2004 4:14 am
by Mike
oh wait, that one you have to remote control. The one I saw had sensors and stuff on it to stop at the edge of the grass.

Re: Remote Control Lawnmower

Posted: Thu Jul 15, 2004 4:17 am
by dyarker
Massively cool :cool: 9hours at that point, and under a kilobuck.<p>I'll agree with kill switch, and auto shut-down on loss of receive RF.<p>Turns well considering long wheel base; and you said you're shortening it.<p>I can't see alternator in photos, but its probably my eyes.<p>I don't agree with Jolly about powering wheels with gas engine. Too many high powered selinoids pushing on belts. A bear to keep adjusted. Rule number 2 applies, it is your mower not mine and not Jolly's.<p>Impressed,

Re: Remote Control Lawnmower

Posted: Thu Jul 15, 2004 9:33 am
by dburlesn
This is the third one I have made.
#2 was gas engine with belt running to a gearbox with counter rotating shafts for the outputs.
One shaft drove a chain running to a worm gearbox that drove one wheel. The other, shaft, another gearbox, another wheel. One wheel for forward, one for reverse. Each gearbox had a built in engage/ disengage lever. Two really big RC servos moved the levers. For steering I used a power window motor assembly. I then hooked up a RC servo to the throttle. I ran everything with a Basic Stamp 2sx. My RC receiver outputs went to the Basic Stamp and it drove the Servos. Everything worked but it was only good for level ground. I will try to find pictures of it. It was very complicated and took several years of off/on work. I had well over 100 hours in it, and $1,000.00 plus. maybe two thousand. What with changes, purchasing new parts, gears, chains etc. etc. etc. And I was NEVER happy with it.
So one day I saw some motors on ebay and built this as a test to see if the motors, batteries, etc. would work well enough to put any more time into it.<p>
This mower was built for mowing fence rows at my mom's house. Plus mowing under low trees, hill sides, grass that is very thin and has little rocks that the blades pick up and pound your legs!!<p>
oops got to go ..... more ramblings in a hour or so.....<p>David

Re: Remote Control Lawnmower

Posted: Thu Jul 15, 2004 4:59 pm
by jwax
Question: Have you approached the goal of RC grass cutting by chopping grass from 4" to 2" as the end objective?
You'll find the gas motor, although cheap and powerful, is an altogether waste of energy while contributing to the awful acoustic, safety, and environmental damage they do.
My point being, grass can be cut all-electric, safely, quietly and efficiently.
I don't know if you have commercial intentions for your device (I had for mine), but be sure to read, follow, and comply with the Consumer Product safety rules start to finish. You'll be up against current manufacturers of 5 million/yr+ gas mowers that sell for $100. Tough market.
Have you considered low-inertia spinning discs with kick-back blades instead of the 1/4" steel bar blade standard on gas mowers? How about motors-in-hub? (The stator is the attached to the base, and the rotor is the wheel)
Please keep us posted! It's not just an entertaining robot, it's functional!
John

Re: Remote Control Lawnmower

Posted: Fri Jul 16, 2004 8:32 am
by dburlesn
I have never considered an all electric mower.
I never know how high the grass is going to be.
It could be hay !!! :)
I am using a 8hp riding engine for a 21" blade.
And If that won't do it I have a 16 HP twin waiting!<p>I have also never considered selling them.<p>Every mower I have made or am making are for my mom's 30 acres. She has fence rows low trees and wide open fields. My father built a 9 hole golf course, and after his passing, I still feel the need to keep it mowed. We have three tractors, a few riding mowers, walk behind mowers, and weedeaters. Lots of hills and hard to mow places.<p>The RC mower was never intended to allow me to sit and play, but for me to walk 10 - 20ft behind it down the fence row. Mow some banks, etc. even on the hottest days of summer.<p>As for selling it, The only time I thought of that was the other day when the lady next door started paying someone to mow her grass. I thought, she could use my RC mower because of the electric starter, and Remote Control.<p>I figured she could be 100 years old and still mow her grass. As long as her eyes held up!<p>
David

Re: Remote Control Lawnmower

Posted: Mon Jul 19, 2004 6:26 pm
by John Paul
The problem with that is you'll end up mowing you're control cable.<p>John Paul.

Re: Remote Control Lawnmower

Posted: Wed Aug 11, 2004 10:07 am
by dburlesn
Posted new pictures of new mower.
I used this one for about 4 hours now, and have many changes in mind.<p>David