I am running Raspbian with BlueZ 5.30 and a Cambridge Silicon Bluetooth USB Dongle installed. I can successfully bring up the BLE interface, as well as detect and connect to a TI SensorTag over BLE when logged in as "pi" and using sudo in front of every bluetooth command (such as hciconfig, hcitool, gatttool, ...)
Is there a way to set things up (file permissions, group memberships, etc.) so that a regular (non root, student) user can connect the the SensorTag (and other BLE peripherals) without having to use sudo?