RC Lawn Mower

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Born On:
15:05, 22 April 2010 (CDT)
Last Updated:
14:30, 20 January 2012 (CDT)


Remote Controlled (RC) Lawn Mower that Ratmandu was talking about.
See example here: http://members.iinet.net.au/~tnpshow/RCLM/intro.htm

We have a mailing list for the mower here: http://lists.makerslocal.org/mailman/listinfo/rcmower

Pictures of the progress we're making are available here: RC Lawn Mower/Pictures

Volume 22 of Make Magazine Features a DIY RC Lawn Mower: http://www.makershed.com/ProductDetails.asp?ProductCode=9780596807177


RC Lawn Mower/Status Archive

  • Transmitter
    • Transmitter is the 8UAFS <-- manual
    • We are able to set the failsafe on any channel. Omegix learned how to do this. --Omegix 21:14, 2 November 2010 (CDT)
    • Soldered together the battery charger for the transmitter. receiver is powered by standard 9V disposable battery. --Omegix 21:14, 2 November 2010 (CDT)
    • According to other Futuba manuals, the typical Failsafe Channel is #3. The NOR failsafe mode will keep the PWM signal at the last good received state. The F/S failsafe mode will change to a predetermined position. Currently it is set in F/S mode, when it looses signal, it goes to a pretermined position of balls-out (See naval history for meaning of balls out).
  • Motor Control RC_Lawn_Mower/Motor_Control
    • The position that would usually correspond to "off" doesn't work with the motor controllers we're using. This PWM position is hard set in the RC receiver. Instead we'll have to devise a kill switch. Preaux recomments a knife switch on the battery terminal hooked up to a servo. When the remote is communicating, it will send a position to the servo. When the remote stops communicating, the RC receiver will output a default position (like what it's doing with the motors) which we'll make sure will lift the knife switch and kill power to the system. --Omegix 13:40, 18 October 2010 (CDT)
    • The RC system is failing in full throttle forward. Need to investigate failsafe outputs of the controller, reciever, and potentially the motor control board. It's unlikely that it's the MC board. Omegix 10:49, 13 October 2010 (CDT)
  • Wheels
    • Don and Ratmandu connected a spoke between the cog and the wheel to give at least one of the wheels the ability to turn in reverse. This is a great solution compared to welding the fly wheel shut permanently. Omegix 10:53, 13 October 2010 (CDT)


  • Purcahse parts to make a motor controller to replace the victor 883
  • Need to attach last scooter motors\wheels to chassis
  • Purchase 22" metal plating to stretch across the back of the chassis. This is where the circuitry and batteries will be mounted.
  • Purchase Another length of Square tubing.
  • Purchase replacement motor: Ebay


Motors \ Wheels are welded to chassis. See status section for date
Battery Charger, Batteries, and initial motor test completed (one motor not working). Motor Test Video July 26th
Preaux welded steel tubing mounts to the frame where the rear wheels will mount June 26th, 2010
Pumped up tubes with bicycle pump (in jeff's car) May 24th
Purchased tubes for the bicycle wheels. Took measurements and marked the steel tubing that will attach the chassis frame to the lawn mower May 22nd
Omegix Continued Ratmandu's angle grinding effort to smooth out weld spots on the chassis May 19th, 2010
Had our first build on the weekend of May 14th
  • On Friday Ben and I picked up two 8" diameter swivel castor wheels for the front of the mower.
  • Scott showed us how to use the portable band saw to cut 45 degree angles into the steel tubing to make the frame fit together the best. He then put tack weld spots where the pieces met to hold the chassis frame in place.
  • Ratmandu finished the welding job on the rectangle chassis over the weekend.
  • The bolt on the height adjuster is 1/2 inch. The threaded portion is too small to go all the way through the square tubing. Someone suggested we replace the current bolt that came with the mower (the one attached to the height adjuster) with a longer bolt.
May 14,2010
Had our first meeting may 8th. Came up with a design similar to the one in the example link above, except no castor wheels in the front and using bicyle wheels in the back, attached to the motor via bicyle chain. Currently looking for metal for the chassy. Omegix 12:10, 10 May 2010 (CDT)


Potential Materials

  • Bicycle Gear Chains
  • Bluetooth to Serial module (for controlling via internet)

Materials On Hand

  • On Switch (provided by Preaux)
  • Big Red Momentary Kill Switch (provided by Preaux)
    • Could put this in between the wire connecting to the spark plug
  • Two 8" swivel castor wheels ($14 each)
  • Metal Bars for chassis (See metal chassis from example above)
    • Purchased 20' of 1" 14 gauge square steel for $18. ($14 for the bar, $3 to have it cut)
    • Two 48"
    • Two 22"
    • One Solid piece of whatever was left.
  • Two Bicycle Wheels
    • Two tubes purchased for the wheels. ($6 each)
  • Lawn Mower (retrieved from Makers Local craigslist add: http://huntsville.craigslist.org/wan/1715017438.html) ($30 for two mowers)
  • Sea Foam (engine cleaner. the mower took a bit to stay running the first time we cranked it). $10
    • Omegix has in the trunk of his car.
  • Motor Control
    • The Current Victor 883 on the board has a burned out FET, causing the motor to only spin in one direction. Ratmandu said he might be able to fix it with tools like what he has at work, but not with the soldering tools at the shop.
      • Replacement FET didn't take, purcahsed three MOSFETS like the ones originally installed on the Victor 883. $12.
    • PreauxPhoto has one of these available: http://www.firstwiki.net/index.php/Victor_884
      • This microcontroller will take in PWM and output enough current to drive larger motors
  • Motors
    • Purchased another 24V 13.7A motor identical to the working one we got from Micheal Spiceland / Opticron. $33
    • PreauxPhoto has 12V DC Motors
  • Battery (for powering the electric motors)
    • Spacefelix said he would donate his battery in the storage room to the project if we wanted it
  • Battery (for powering the electronics)
    • Preaux has provided a special battery that is resistant to loss of power due to vibrations, etc)
    • Currently in Omegix car trunk. Omegix 12:40, 26 May 2010 (CDT)
    • battery dimensions: 4.5"D x 8.5"W x 5.5"T
  • RC Transmitter and Receiver Unit (hobby RC receivers output PWM signal)