The challenge

• Incorporate 5 motorized and remote controlled functions in a 1:14.5 scale model.
• Make the rear axle pendular while steered and driven

Video below.

Functions

• Forward/reverse
• Steering
• Boom lift
• telescopic boom
• Bucket tilt
• Pendular rear axle
• Quick coupler

The front axle. In real frontloaders the quick coupler is very close to the front axle in order maximize lifting power without the machine tipping over. In order to achieve that in my model I used the frame from the steering ball joint instead of the ordinary 5x7 frame typically used around the differential.

The rear part with the pendular suspension. The L motor is for lifting the boom. The clutch gears enables two functions over one axle, in this case used to transfer steering and drive to reach the rear axle.

The chassis almost complete. Some of it has been rebuilt. 

I am very happy with the results, with two important exceptions; first, I more or less had to use a worm gear in the drive train which made it very slow and, second, the rear wheels’ steering is very inaccurate since the steering transmission passes two “pairs” of 8-tooth gears along the way.