How to get crispy vegetables chips/fries without frying?
There are lots of recipes for oven-"fried" sweet potato chips (crisps) and fries (chips) and I'll let you search that part. I've noticed a wide variation in recommended oven temperatures, from as low as 350 to as high as 450. Though I've never had great success with crispiness, my overall best results were with a temp of 425.

Crispiness with sweet potatoes is notoriously difficult due to the high water and sugar content (which will caramelize and make them appear and to some extent taste burnt, usually long before they crisp up). There's some discussion of this on Chowhound. 

Key points seem to be:


remove as much surface moisture as possible prior to cooking
avoid overcrowding the pans, especially when cooking thicker cuts
use a convection oven if possible


If you have success please report back and tell us what worked!