Vulcan/packages/vulcan-voting/lib/modules/permissions.js

import Users from 'meteor/vulcan:users';

const membersActions = [
  'posts.upvote', 
  'posts.cancelUpvote', 
  'posts.downvote',
  'posts.cancelDownvote',
  'comments.upvote', 
  'comments.cancelUpvote', 
  'comments.downvote',
  'comments.cancelDownvote'
];
Users.groups.members.can(membersActions);