No need of bed. I can happily sleep by simply sitting in a chair. But I don't have the habit of having a nap after lunch. This may be due to my working hours. I eat lunch around 10 AM and go to office. Lunch of some fruits or sprouts in the lunch in the office. Light dinner in the night. So I have no practice of sleeping the office. But I sleep in my car while travelling without any disturbance. Even travelling in trains or buses or flights, I sleep.