My steering geometry was square. The steering wheels were always parallel to each other. However, if a car is cornering the outside wheel is making a large circle, the inside wheel is making a small circle. So, the steering angle of the outside wheel should be less than that of the inside wheel. This can be achieved with a steering geometry called Ackerman steering geometry. See the image I took from Wikipedia.

I wanted Ackermann steering. This forced me to redesign the steering mechanism and to recalculate some of the cars properties. The biggest challenge turned was to make the design sturdy. On the run I also managed to get rid of some of my previous design errors. Although I introduced some new ones.

As both front wheel have a different angle this could further complicate calculations. To overcome these complications I now base all calculations on a fictional front wheel that is placed exactly between the two real ones and that has an angle that is the average of the to real ones.

Here are two new pictures of FreeRover. One showing the steering mechanism. The other showing FreeRover in its current state. You might notice the red handle bars. These are intentionally red as the remind me to use them while handling the car. Before that I used to grab the driving motors while carrying FreeRover. Sometimes this would cause the cables to disconnect.

I had to compromise on sturdyness and cornering. It turns more slowly than it used to. Was it worth it? I don’t know.

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