riding a bike

I have had Parkinson's Disease for approximately 4 years. I am able to get around well, but walking any distance is very tedious for me. I tend to drag my right leg and it is tiresome. Riding a bike is so much easier for me to do. I am sure many of you have seen videos where a person in advance stages of Parkinson's can actually ride a bike with little difficulty. I recently was visiting my daughter in Chicago and we walked about 3-4 blocks to a restaurant. It was a beautiful day, but I did not enjoy the walk as I was too busy just concentrating on the idea of walking. I wish someone would invent a "pedal chair" to get around in. Tricycles are too large. I would like a small chair with wheels and pedals that you could use on a sidewalk as well as around your home. It would be so much easier to get around this way. Does anyone else have similar thoughts?