This is one I've been thinking about for a long time. Some issues that come up with the TerraTrike Steering are:
1. Turning radius is too large.
2. Bushings in the hubmounts wear and can eventually cause the steering to be sloppy.
3. The front fender mounting system is complicated and makes changing a tire difficult.

Our new system must:
Be 100% compatible with the existing steering system.
Use bearings instead of bushings.
Include direct-steer option to cut turning radius.
Include fully adjustable steering system with direct-steer option.
Include improved fender mounting system.

This was one of my first ideas for the hubmount. I had a basic idea of the shape I wanted and how to incorporate a direct steer mount.

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In order to work all the clearances out properly I ended up modeling the TerraTrike frame. This allowed me to have a virtual prototype that I could actually use to test the motion and discover clearance issues.

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Here's a closeup of the hubmount with all the clearances adjusted for. As you can see our hubmount is compatible with the stock steering system by using the end hole. The new tierod is connected to the inside hole which provides for accurate Ackerman compensation.

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Finding the bearings that can handle the right load was a challenge. As you can see the bearings are a pressed fit and are isolated from the frame by the spacers. A tight fit assures that the bearings wil spin and the kingpin will stay stationary in the frame.

You can also see the quick release axle tubing which allows the wheels to be removed without removing the brakes as is the case with the stock setup.

We've had a lot of responses on this project. One thing you guys want is more flexibility with the handlebars, so here you go. This will be a lot easier to fabricate too.