long story short: in the end i managed to build a bike that has the above features, but has simply become too heavy to load anything on it. plus steering is something you really have to learn with this monster:
Step 1: Research
also very inspiring are tilting tricycle constructions built before:
- the jetrike: http://www.jetrike.com
- onya cycles' front-end loader. unfortunately the website (http://onyacycles.com) seems to be dead, but here are a some impressions: http://tinyurl.com/as2cc5m
- youtube has quite some videos about tilting trikes: http://tinyurl.com/ajkp98w
Step 2: An Early Prototype
Step 3: Building the Trike: Lean-steer Part
the first part to build was the lean/steer mechanism. as you can see in the first photo the core part are ball heads which allow a tilt of 30° (2x15°) and, at the same time, the turning of the wheel axles. in the second image you can see how it tilts.
Step 4: The Frame
Step 5: First Test Assembly
Step 6: Steering
Step 7: That's It!
- too heavy
- the wheels are way too far in the front and
- steering is a pain in the a**
the project took quite some time and i also spent a little bit too much money for my taste, but i'm sure i can use the knowledge i gained in the one or the other way.