pcl_surfel_smoothing_test: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/pcl_surfel_smoothing_test - from package: pcl-tools

You may install the required package with command apt-get install {package}

Error in other languages:
pcl_surfel_smoothing_test: bevel nie gevind nie
pcl_surfel_smoothing_test: comandă negăsită
pcl_surfel_smoothing_test: comando não encontrado
pcl_surfel_smoothing_test: commande introuvable
pcl_surfel_smoothing_test: command not found
pcl_surfel_smoothing_test: käsku ei ole
pcl_surfel_smoothing_test: không tìm thấy lệnh
pcl_surfel_smoothing_test: komanda nerasta
pcl_surfel_smoothing_test: Kommando nicht gefunden.
pcl_surfel_smoothing_test: kommandot finns inte
pcl_surfel_smoothing_test: komut yok
pcl_surfel_smoothing_test: nie znaleziono polecenia
pcl_surfel_smoothing_test: níor aimsíodh an t-ordú
pcl_surfel_smoothing_test: no se encontró la orden
pcl_surfel_smoothing_test: no s'ha trobat l'ordre
pcl_surfel_smoothing_test: opdracht niet gevonden
pcl_surfel_smoothing_test: parancs nem található
pcl_surfel_smoothing_test: perintah tidak ditemukan
pcl_surfel_smoothing_test: príkaz nenájdený
pcl_surfel_smoothing_test: příkaz nenalezen
pcl_surfel_smoothing_test: команда не найдена
pcl_surfel_smoothing_test: командата не е открита
pcl_surfel_smoothing_test: 命令找不到
pcl_surfel_smoothing_test: コマンドが見つかりません