Repkovsky

And you can find the stud.io model here (great page https://fogeyman.tistory.com/1158).

Thank you! Maybe that is because I was less constrained by time and allowed building techniques than LEGO designers. Thanks! 42128 is great set for building alternative models, but the color scheme is indeed a bit crazy, adding another level of complexity to building nice-looking MOC :). I think most of the AFOLs community does... Yeah... I didn't want to build yet another cab-over-truck design, since there is a couple of such alternatives to 42128 already. As a result, I decided to build smaller truck with lower cabin, but that constrained a room for engine very much. Even with this location, steering was quite hard to accomplish, as there is small room under the engine.

As the new 42144 Material Handler was often compared to 42128 Heavy Tow Truck in terms of number of elements and price, I decided to make an experiment and build Material Handler from 42128 to see if the similar functionalities can be achieved using its parts only. As a result I was able not only to reproduce Material Handler, but also introduce some improvements and build Dump Truck using remaining parts. Two thin pneumatic cylinders were used in the upper part of the boom, which actually better resembles design of most material handlers. Small pneumatic cylinder was replaced with small linear actuator, which makes the grabbing far more robust. To keep the location of all controls at the back of superstructure, the drive of small LA is transferred all the way from knob at the rear wall of superstructure, through the middle of body and boom, to reach the grabber at the end of upper arm. Upper arm has full range of 90 degrees movement, thanks to the special orientation of universal joints. HoG steering is located opposite to the steerable wheels. 4 outriggers and cabin raising are operated similarly to 42144. Dump truck has 4-piston engine connected to rear wheels using differential. Cabin has openable doors, dump is raised using two small linear actuators. More pictures at https://bricksafe.com/pages/Repkovsky/42128-material-handler--dump-truck-moc-123531 Instructions are available to buy at https://rebrickable.com/mocs/MOC-123531/Repcovsky/material-handler-dump-truck.

I think below picture shows their independent movement. What is more, if you look closely you can see small turntable in the center between 5x7 frames.

I think steering is now much easier and more responsive - at least for me smartphone app has an annoying lag when it comes to controlling Large Angular Motor. The problem is actually in the motor itself and quite large momentum required for turning the hauler. It is rather hard to perform precise turning for the given angle with such high friction and load. In the case of Bluetooth remote turning is always set to maximum range, so precision is not required and motor can be rotated faster and more robustly.

I have written a Pybricks code for controlling 42114 using 88010 Bluetooth Remote. Both manual and automatic gearbox modes are available, so the functionality is similar to the one offered by the smartphone app. Detailed installation instructions, operation manual and the code itself can be found at https://github.com/repkovsky/technic/tree/main/42114-volvo-articulated-hauler, below I attach a little demo. @Tcm0 I noticed you are collecting remote control programs for Technic sets on your Github, you can include also link to this one, if you want :).

Yes, this is because there are 5 gears inside instead of just 3, so the risk of slipping or damaging 8-tooth gear is much lower as the forces are spread to more elements.

Big tyres of 42081 Volvo Concept Wheel Loader inspired me to rebuilt it into off-road truck. Availability of linear actuators suggest some lifting, so tow truck seems to be good idea. The result is Off-road tow truck TAUROX (to continue the original mythology- and astronomy-originated names ZEUX and PEGAX). There are two version of the truck - alternate built with no additional parts, and extended 4x4 PF-powered RC version, where I tried to minimize additional elements (as a challenge). This was not easy to do, since 42081 has very small number of gears and other elements specialized for building drivetrain for off-roaders, but essentially it worked. Pendulum suspension with torsion bars is used both in front and rear axles, and designed to avoid stressing bars (9-axles) in neutral position. As in the RC version motors are located in the central part and so is the HoG steering in non-RC version, the axles used as an rotation axes in pendulum suspension are used also for passing the propulsion/HoG steering. This introduces friction, which could be avoided by using turntables for supporting the pendulum suspension and passing the driving/steering axle through the middle of turntable. But as I wanted to avoid using additional parts, there is an alternative solution based on regular liftarms and pins only. Final drivetrain in RC version is rather simple and works well for moderate load, but I think there may be enough space for adding central differential, or strengthening front/rear gearing. HoG control version: RC version (2xPF-Large, 1xPF servo) In both versions boom is operated manually, as well as lowerable hook: Little demo: More pictures can be found at BrickSafe: https://bricksafe.com/pages/Repkovsky/48081-off-road-tow-truck-taurox-moc-79275 Instructions for building are available at https://rebrickable.com/mocs/MOC-79275/Repcovsky/off-road-tow-truck-taurox/. They have about 300 pages each, and are divided to submodels to make building easier, more complicated steps have additional arrows to improve clarity. Here is a sample of instruction https://bricksafe.com/files/Repkovsky/48081-off-road-tow-truck-taurox-moc-79275/taurox_rc_sample.pdf. Any comments are welcome.