Storage Space : How to get real disk usage outside server manager? (Powershell ?)

hi

i use storage space on headless windows2012 server. 

server remotely managed , use tool mobilepcmonitor  to monitor , being alerted when appends (update, cpu/ram workload, temperature, drive health, etc)

but storage spaces (with fin provisionning) can't manage real free space on real drive.
have 50tb storagespaces, "only"  10tb of real disk space, , half used.

with monitoring tool can check 50tb virtualdrive, can't find way know real disk space, , real free space. .
these values exists, , can find them under proprieties of storagepool windows server manager.

i've checked performances counter, find nothing storagepool related.
i'm looking find theses value powershell, find nothing (checked docs can find on technet, unsuccessfully)

the goal notified when real drive start full can manage add new drive on pool... today need manually check on server manager, else can monitored through simple tool mobilepcmonitor or snmp.

does here know how can fetch these datas ?

thanks

thanks yours answers found looking for, having direction search:

http://msdn.microsoft.com/en-us/library/windows/desktop/hh830532(v=vs.85).aspx

get-wmiobject -namespace "root/microsoft/windows/storage" -class msft_physicaldisk -property friendlyname, size, allocatedsize, healthstatus,model | format-table friendlyname, model, size, allocatedsize, healthstatus

thanks !

Windows Server  >  Windows Server 2012 General