NIST Additive Construction 

Laboratory

Scott Z. Jones, Ph.D.

Infrastructure Materials Group

Ph: +1 301 975 4948

Email: scott.jones@nist.gov
The Additive Construction Laboratory features a six axis, six degree of freedom articulated robot arm mounted to a 

10 m 7th axis track. The arm has a 3 m reach with 150 kg payload for an approximate build volume of 3 m x 3 m x 

10 m. Material is supplied to the robot by a dry mix grout pump. Two nozzles are available: a single component and 

two-component nozzle

• Robot Model: IRB 6700-150/3.20

• Degrees of freedom: 6 DOF + 7th linear axis

• Operating speed: maximum robot speed is 1.6 m/s. Print speed is limited by the flow rate of the grout pump which 

ranges from 0.08 L/s to 1 L/s

• Resolution: The single component nozzle has a diameter of 23 mm and controls the resolution of the printed 

objects. The robot has a positional repeatability of 0.10 mm and a path repeatability of 0.15 mm

The dry mix grout pump is the m-tec Duo Mix 2000, a positive displacement pump capable of pumping grout with a 

maximum aggregate size of 4 mm. It is integrated into the robot controller can can be operated from the robot teach 

pendant. The pump flow rates are calculated from the robot speed and user-supplied filament geometry.

The two-component mixing nozzle adds a second component to the grout material at the nozzle. Pumping hardware 

for the second component must be designed to fit user applications.

Overview

Additive Construction Laboratory
Robot and Grout Pump

Left: ABB IRB 6700-

150/3.20 mounted on

the 7th axis linear track.

The single component

nozzle is fitted to the

end of the of the 6th

axis. A 6.35 cm ID

flexible hose supplies

grout to the nozzle

Above: M-tec Duo Mix 2000 grout pump located 

behind splash shield. The pump is integrated into 

the the robot controller and can be controlled by 

the robot or by an operated using the robot teach 

pendant. The maximum aggregate size is 4 mm.
Available Tools and Mounting Flange Tool flange, standard

Below is the standard tool flange. The guide pin hole is, in calibration position,

pointing upwards in Z-direction.

22

101

12

3x R 0,8 -0,4 +2 3x R0,8 0

+1

1x45

2,5

A

B-B

A

A

B

B

A-A

xx1300000280

A Thread length: 18 mm.

The turning disc for robot variants IRB 6700 - 200/2.60 and IRB 6700 - 155/2.85

was redesigned when Axis Calibration was introduced for IRB 6700. Prior to Axis

Calibration the holes on the disc were through. On the current turning disc the

holes are not through.

Fastener quality

Use suitable screws and tightening torque for your application, screws with quality

class 12.9 are recommended.

2.4.8 Fitting equipment to the robot

Continued

Left: The single component nozzle with 23 mm ID. 

Right: Two-component mixing nozzle. Component 

1 is supplied by the grout pump and component 2 

is supplied by user-supplied hardware.

Above: Tool mounting flange dimensions. Full CAD 

files for the IRB 6700-150/3.20 are available here: 

https://new.abb.com/products/robotics/industrialrobots/irb-6700/cad-models
Layout of Additive Construction Cell

DETAIL A 

206/RM108

2 1

A A

B B

Roll up door

(to exterior)

42.00

148.90

86.14

15.00

32.50

2 1

Print Area

Observation Area

Pumping 

Area

Control

Area

Emergency Stop Emergency Stop (located on Flex Pendant)

Power Disconnect

Controller on/off

Light stack Indicator

Light Curtain boundary

Interlock

Grout Pump

Parabolic Mirror

Exterior Door

Exterior Door

To Room 107

North

South

West East