+* h_stay_on_table
+ - [ ] locate materials
+ - [ ] challenge-bot, laptop, usb cable
+ - [ ] connect arduino and computer with usb cable
+ - [ ] on laptop, in arduino, open h_stay_on_table sketch
+ - [ ] close other arduino windows
+ - [ ] upload with control+u
+ - [ ] wait for upload to finish
+ - [ ] unplug usb cable
+ - [ ] turn on clear motor battery pack
+ - [ ] turn on black arduino battery pack
+ - [ ] set robot down on a its box or a table
+ - [ ] check that robot stays on the table
+ - [ ] check if robot can roll off an edge at a shallow angle
+ - [ ] if it does, check if you can change the placement of the
+ sonars to detect approaching an edge from a shallow angle.
+ - [ ] turn off clear motor battery pack
+ - [ ] turn off black arduino battery pack