diff --git a/hbp_nrp_virtual_coach/requirements.txt b/hbp_nrp_virtual_coach/requirements.txt
index 298f56e98707c723c5898a247e4b355aaafec318..4da393e62a30f471f3da583d58e6243a31c50da9 100644
--- a/hbp_nrp_virtual_coach/requirements.txt
+++ b/hbp_nrp_virtual_coach/requirements.txt
@@ -6,6 +6,7 @@ texttable==0.8.7
 progressbar2==3.34.0
 httplib2==0.12.1
 pandas==0.22.0
+ipywidgets==7.5.1
 jupyter==1.0.0
 requests
 ipykernel==4.6.0