The 18-year-old pair, who have put pen to paper on two-year deals, will be included in Craig Sandercock's squad for the 2014 season.
"Both Josh and Connor are players from our academy system who we think can kick on and have successful careers here at Hull Kingston Rovers," Sandercock told the club's official website.
"I was happy with Josh on his debut against London and his skill set is definitely there. He knows he still has a lot to work on and the pre-season will be important for him, especially in terms of physical development. He's only 18 and is still filling out so to speak but we'll be working hard with him.
"Connor is another local boy who has come through our academy system and like Josh, he has a good skill set. Pre-season will also be very important for Connor and he fully deserves the opportunity to develop further in our first team squad."
Full-back Guzdek has already featured for Hull KR's first team, having made a try-scoring debut in last month's 34-22 defeat to London Broncos.
Robinson, who can operate as a hooker or in either half-back position, has been has been at Craven Park since the age of 12.