Page 15 of 15 FirstFirst ... 51112131415
Results 141 to 148 of 148

Thread: More Mule then Rover?

  1. #141

    Re: More Mule then Rover?

    I like them wheelchair motors for projects.

  2. Re: More Mule then Rover?

    Click image for larger version. 

Name:	george1.jpg 
Views:	70 
Size:	142.7 KB 
ID:	7145
    working on cameras

  3. Re: More Mule then Rover?

    I like them wheelchair motors for projects.
    they are sweet motors, I have some with factory encoders in them.

  4. #144

    Re: More Mule then Rover?

    I like the light mount. Seems like it should get enough distance to give a more even spread than if it was just placed in front like headlights?

  5. #145

    Re: More Mule then Rover?

    I think Tician's point is that forces, over time, may fatigue the metal when all the stress is concentrated. Building a "chassis" of two long bars, and bolting things onto that, would generally distribute the stresses better. If stresses aren't big enough, then it kind-of doesn't matter, which seems to be your assessment?

    I have no idea whether your mule is actually close to a critical point or safely designed, I'm just interesting in running the numbers pointed out by Tician.

    I looked up 1/2" steel bolts. Safe working load for a 1/2" bolt (grade 2/5/8) is 940 pounds shear, 760 pounds tensile. (Catastrophic failure, i e immedite breakage, load is about 10-20x higher, depending on grade.) Will your bot weigh 760 pounds or more? Will it rock left/right such that weight is unevenly balanced? Will it get stuck and apply more torque, or bump into uneven terrain so the load is increased by inertia? If so, 1/2" bolts may fail over time. The table I used:

    "hardened steel"
    If durability under bending stress is what you want, hardened will crack sooner than less hard steel. It of course depends on the specific loads, but too much carbon makes it brittle. There is also tempering where you harden, then "back off" by relaxing in medium heat for a bit, which gives a better trade-off between brittle and touch. Maybe that's what you're using?

  6. #146
    Join Date
    Jun 2011
    Rep Power

    Re: More Mule then Rover?

    I bet it will survive the few years before his next iteration!

    Looking marvelous as always, Tommy!

  7. Re: More Mule then Rover?

    I like the light mount.
    jwatte, a work in progress, the parts I have done so far are the snow plowing attachment, but I want the lighting and cameras systems
    on the main unit(back section not made yet).

  8. Re: More Mule then Rover?

    the best I can do is 300lb per tire.

    If I had to question something, it would be the main axle brackets.
    but the last frame used the same setup and held for four years.

    Click image for larger version. 

Name:	weak2.jpg 
Views:	71 
Size:	81.3 KB 
ID:	7146
    Last edited by Tommy_T; 01-28-2018 at 12:54 PM.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Project Second Rover Build
    By Sundsted in forum Rovers
    Replies: 3
    Last Post: 07-17-2010, 03:04 PM
  2. First rover bot project!
    By Carlcox89 in forum Rovers
    Replies: 4
    Last Post: 07-01-2010, 05:55 PM
  3. Fit-Bot - a Fit-PC based rover
    By coppertubing in forum Robot Computers
    Replies: 9
    Last Post: 10-06-2009, 08:32 AM
  4. Xan's Rover with Arm
    By Xan in forum Rovers
    Replies: 14
    Last Post: 07-18-2009, 01:16 AM
  5. Discussion Rover Kits
    By LinuxGuy in forum Rovers
    Replies: 0
    Last Post: 04-02-2008, 04:48 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts