I used to be a full time doodler and a some times sketcher until in the early 70's I read Frederick Franck's The Zen of Seeing Drawing. His approach to seeing/drawing changed everything for me. I stopped worrying about what others might think of what I was drawing and began sketching for the pure pleasure of it. In those days as a sales representative I spent hours on the road covering the states of Washington, Oregon, Idaho and Western Montana. I thought if I apply the tenets of seeing/drawing - allowing my eye to guide my hand without looking at the paper - while I'm driving, what might I be able to capture on paper at speed? All of a sudden my long road trips became a lot more interesting. I constructed a portable easel/table that sat in the passenger seat of my car. My paper, pencil and watercolors were within easy reach. I knew whatever I sketched was not going to be full of detail, I just wanted to see what I could sketch. My approach was simple. On long straight stretches I would look ahead at the horizon, pick something out like a road sign or whatever I could use for a marker, keep my eyes focused on that marker and begin drawing. What could I get on paper before I passed the marker was my challenge and based on an average speed of 70 MPH I had to be pretty quick.
With all the inherent dangers of distracted driving our culture is dealing with from the use of our cell phones, texting etc., no wonder most states have laws on their books prohibiting texting while driving. On the other hand, as far as I know, there are no laws concerning sketching while driving.
While I do not recommend sketching and driving, I do suggest, if you haven't already done so, to add Frederick Franck's The Zen of Seeing Drawing to your art book reading list.