Block Masonry Gets A Lift Mule Carries The Load Of CMU

Robot Carries the Load of CMU for Placement

Scott Peters, Nate Podkaminer, RA

Block Masonry Gets A Lift Mule Carries The Load Of CMU

Scott Peters, Nate Podkaminer

Concrete Masonry Units (CMU) have been an important part of masonry as a strong, flexible and durable material for building construction. Because of its cost efficiency and attributes including fire resistance, acoustic performance, low maintentance and durability, CMU are used throughout the building, from foundation, structure and enclosure to interior partition walls to exterior finishes.

As with any construction material, larger unit sizes have higher expectations of square feet placed per day. One of the limiting factors to this concept is the ergonomic limits of the human, in this case the mason, who performs the same repetitive task day in and day out. Larger and heavier CMU are used in foundations, backup walls, split-faced exterior finishes and integrated with insulation for a complete interior/exterior wall system. In addition, CMU are often designed with higher solids in each unit for walls with fire ratings and higher seismic designs. Today, a typical 8x8x16 unit weighs about 30-35 lbs.

Construction is one of the most physically demanding careers and laying masonry is no exception. In order to protect craftsmen from injury and prolong their careers, the industry continues to innovate materials and methods.

Construction Robotics is excited to introduce the MULE (Material Unit Lift Enhancer), a lift-assist robot that is flexible, easy to setup, easy to use and completely operated by the craftsman on-site. The robot will be used by masons to improve health and safety, increase productivity and improve the overall work-life of masons. It is built to carry the weight of whatever it is lifting, while allowing the mason to interact with the block (or any material) naturally and effortlessly.


MULE takes the heavy load away from the mason when laying CMU, stone or other heavy materials. The average mason lifts 4,000 to 10,000 lbs daily when laying CMU. That’s like lifting his pickup truck each day! With the MULE, this daily load will be reduced to approximately 150 pounds per day.

The MULE is a lift-assist robot operated by the mason to facilitate his craft. Once setup, it can reach over 22’ of wall, run on a 110v plug and can be up and running within minutes of arriving onsite. The mason controls the robot and individually grabs the CMU with the pneumatic end-effector. With the CMU in the MULE gripper, it is weightless and floats in the air. A mason can then move the block up, down and to the wall, with no weight or strain on his body. He can lift a 135 lb unit up over his shoulders and over rebar with the push of one finger, eliminating risk of injury. As the mason effortlessly moves the CMU to the final position, he presses a button to engage a proprietary and unique Set mode that allows the mason to automatically add some weight to the block allowing the mason to lightly set it naturally in the mortar bed.

Early studies and field test results have demonstrated a potential for 200% to 400% increased productivity.

Once he has checked the line and level, he hits the release button. The machine takes over from there, not immediately releasing or dropping the CMU, but instead, ramping down on the lift assist at a controlled rate to make sure the CMU is set on top of the mortar and does not squeeze it out. The process is repeated for the next unit, all in a matter of seconds. This seamless and intuitive operation and integration between the mason and the robot is not only easy to learn, but natural and fun to work with.

"Weightless" block held in suspension by MULE waiting for mason to place it in the wall»

MULE can work a 22' span of wall and free stand to heights of over 20'MULE can work a 22' span of wall and free stand to heights of over 20'»


Flexible deployment is important when considering any construction product. The robot has been developed to go everywhere, with a variety of base configuration and gripper attachments. It can be operated with wheels on the ground, incorporated with scaffold, or deployed on mast climbing work platforms. Interchangeable grippers allow the contractor to change from block to cast or natural stone in a matter of minutes by simply unpinning and unplugging the lower gripper and installing a new one. Construction Robotics envisions the MULE will be widely utilized to provide precise control when lifting and placing products on a job site. This new concept of using technology to remove heavy lifting and interact with the product onsite can significantly change the way masons work.

A mason easily maneuvers an oversized block over rebar on an elementary school project in Pennsylvania»


The robot allows experienced masons to remain productive and injury-free much longer into their career, allowing business owners to retain their most senior and knowledgeable craftsmen. The robot draws the interest of the younger generation entering the industry by reducing the physical demands and inherent fatigue through utilization of the next evolution of technology. The physical size and strength of the masons will have less impact on who is available to lay block. These benefits help to reduce any shortage of qualified masons and increase the number of future masons.

Above: Two buttons are primary controls for the MULE and are easily positioned for ergonomic comfort of the masonAbove: Two buttons are primary controls for the MULE and are easily positioned for ergonomic comfort of the mason»

Left: With MULE, masons can fine tune the “feel” for moving and setting block



We know what an amazing product masonry is through real life examples. It has endured in buildings around the world for centuries. It has some of the industry’s best safety and lowest maintenance characteristics. With the emphasis on first costs, other less enduring products may be considered, sometimes without regard for durability or maintenance or even life expectancy. Regardless, masonry is facing increased competition as budgets are developed and value engineering seeks to lower the total construction cost. This needs to change. The MULE can help lower in-wall cost of masony.

Robots increase productivity and reduce installed cost per square foot for block. There have been countless studies to evaluate the impact of repetitive lifting of heavy weights. It is well known that lightweight materials can increase the productivity of CMU installations. When comparing the productivity of laying a 40-lb CMU to the same unit in a practically weightless condition, the productivity with the weightless should increase. Early studies and field test results have demonstrated a potential for 200% to 400% increased productivity. These gains are just the start. With MULE, new sizes of materials that take advantage of the 135- pound lift capability will further increase the square feet placed per day by masons. The ease of use of this robot is field validated. Advantages of greater productivity with less risk of injury will bring both tangible and intangible benefits, including cost savings, to each job.

Scott PetersScott Peters


Scott Peters is the co-founder and President of Construction Robotics. He has held various roles in engineering and management across a range of industries over the past 15 years. Scott has experience developing advanced manufacturing technologies and robotic automation concepts. At CR he has led the team from concept to completion of the world’s first prototype Semi-Automated Masonry (SAM) robotic brick laying system. Scott is an inventor and entrepreneur and has invented technologies in numerous industries. 585.742.2004 |[email protected]

Nate Podkaminer


Nate Podkaminer, RAis the co-founder and visionary behind the Construction Robotics concept. Nate is a Registered Architect with over 40 years of experience managing multimillion dollar construction projects and, as an industry innovator, has brought many new construction concepts to the region. He is a senior executive with the Hueber-Breuer Construction Company in Syracuse and was critical in the growth of the company from 4 employees when he started in 1975, to over 45 today. 585.742.2004 |[email protected]

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