Dump truck

[Zerobricks]

Here's my new rather simple MOC. Because doing a simple dump truck is well....simple, I decided to spice things up by adding suspension and using only 2 motors to do 3 functions.

So how can you use 2 motors for three functions? The answer is rather simple. I used a differential connected to steering system. As soon as the steering rack reaches its maximum position, the power is diverted to the LA, which lifts the bed. In order to make sure that the steering will always work before the LA i Used some friction pins parallel to the LA functions, to make sure the differential will always steer first.

The brown gears are from the drive motor. The red ones are froms teering motor. The green diff splits the power where it is needed.

After building this central gear system, there was another problem to solve. The LA is stuated in such manner, simply pushing agaisnt the bed would be very inefficient when trying to lift heavy loads.

After some trial and error i came up with this special linkage, which follows the circular path of the bed, therebye helping it lift, instead of just pushing against it.

The LA in green pushes the brown link, which in turns lifts the bed. The small blue and yellow links are used to make the brown link follow a certain path in which it not only pushes, but also lifts the bed, therebye creating more force.

After adding a tiltable cab, battery box and suspension the truck was done:

I used independent suspension for first and rear axle, whilethe second driveaxle uses double tyres and live axle suspension. The second axle is also configured in such way to carry most of the rear weight.

The cab can be lifted to reveal the receiver.

And a short video of the truck in action:

http://www.youtube.com/watch?v=R9wvAlX7Z-U

All in all its a nifty little truck and very fun to drive arround and dump stuff out, especially bricks. Also by just using 2 motors and only one IR channel, this allows for more RC models to be driven at once like on exhibitions, etc,...

I also made the model in LDD if anyone is interested:

http://www.brickshel...ruck/dumper.lxf

P.s. MOD its dump truck, not Sump truck, please correct the topic name.

Edited February 10, 2013 by Si-MOCs

[MrNumbskull13]

Hey Zblj, you're a great lego technic creator and all your trial trucks and truck vids have inspired me but I thought that idea with the differential was really clever! Overall I'd say this is a simple yet clever, compact, fun, realistic MOC, keep up the great work! :)

[timslegos]

The special linkage looks like it works really well, nice job.

tim

[Ramacco]

Sump Truck = Simple Dump Truck? Thought that first..

Nice model! I'm using an almost same technique in one of my robots which can grab and raise with only one motor.

[Alasdair Ryan]

I was not a fan of the cab.......

I am not too sure if the wheels will hit the cab when the truck steers.

Mod Download

[Carsten Svendsen]

That looks great. What a clever idea of lifting the bed

[DLuders]

@ Zblj: I really like that linkage design! :thumbup: I have been trying to build a powerful dump bed Linear Actuator lifting mechanism to lift heavy loads like that, but I never could get it right. Your design is simple yet elegant. The LA in your video really shows its power. Would you mind if I incorporated your linkage design into a MOC I've been wanting to build for years?

[Zerobricks]

@ Zblj: I really like that linkage design! :thumbup: I have been trying to build a powerful dump bed Linear Actuator lifting mechanism to lift heavy loads like that, but I never could get it right. Your design is simple yet elegant. The LA in your video really shows its power. Would you mind if I incorporated your linkage design into a MOC I've been wanting to build for years?

Sure use it! Its quite powerfull, yes and you may need to fiddle arround the hit te perfect link lengths, but once all is alligned it works flawless. So again USE MY IDEAS, and i mean everyone, thats why i share them and the LDD models!

[jorgeopesi]

Nice and clever linkage .

[DLuders]

Zblj's Dump Truck has been posted on Technicmad's Rebrickable. Thanks for sharing your model, Jernej!

[dvsntt]

The use of the differential was a really clever idea. I like that function.

[jadedomg]

I love dump trucks! I might have to pull apart a few sets to build this one to have on my shelf for a little while.

[Alasdair Ryan]

I love dump trucks! I might have to pull apart a few sets to build this one to have on my shelf for a little while.

You could use the 8109 cab like I did in my mod.