Specifications

Shoulder Yaw: Shoulder Pitch: Shoulder Roll: Elbow Joint: Wrist Yaw: Wrist Pitch: Wrist Roll:	4-Dof 300° 225° 315° 230° – – –	7-Dof 300° 225° 315° 230° 350° 180° 344°
Mechanisms	Mechanical transmissions based on advanced, patented high-speed cable transmissions and patented zero-backlash, low-friction, cabled differentials.
Payload	4 kg	3 kg
Reach (w/ hand or gripper tool)	1 m	1 m
Work Volume	3.5 m3	3.5 m3
Agility Index (avg. joint mobility in radians raised to the # of dofs)	466	44,000
Peak Velocity*	3 m/s	3 m/s
Minimum Velocity	0.2mm/s	0.2mm/s
Peak Accel. (at endtip with 1-kg load)	30 m/s2	20 m/s2
Repeatability	0.3 mm	0.6 mm
Weight
Entire Assembly	25 kg	27 kg
Arm beyond shoulder	3.3 kg	5.8 kg
Size
Footprint	0.1 m2
Base Height	160 mm
Motors	Neodymium-iron, brushless motors driven by high-performance space-vector-commutated current amplifier/controllers
High-Level Interface	High-speed network cable and wireless
High-Level Cartesian Control (Trajectory and/or Force)	500 Hz	500 Hz
Low-Level Joint-Torque Resolution	14 bits
Lower-Level Position Feedback
Type	22-bit digital motor position feedback
Minimum Joint Resolution	0.005°	0.008°
Power Requirement	100-240 vac    1Φ    50-60 Hz
Amplifier Cabinet + Controller PC**
Weight	0 kg	0 kg
Depth	0 mm	0 mm
Height	0 mm	0 mm
Arm Cabinet	0 mm	0 mm
Tether Length	0 m	0 m

 

*A high-speed custom version of the 4-dof WAM is available with peak velocities of 12-25m/sec. This special, customized version of the WAM has been used by University of Tokyo and MIT to produce the very-fast batting and catching applications for the WAM. The components of these WAMs are different that regular production WAMs and crate the following trade-offs:

1. Not safe in reach of people.
2. 20% higher price.
3. 2 weeks additional delivery lead time.
4. High-voltage operation (up to 200 vdc) only.
5. Requires special 10-kg external power supply that must be used for all future applications of that WAM.
6. System has not been tested or approved for use with Barrett’s Wrist module or BarrettHand.
7. Payload is de-rated by half.
8. Creates cable micro-yielding which causes overall cable elongation over time leading eventually to cable fatigue and failure.  Cables may need replacing every few months.
9. The high voltages are not compatible with Barrett’s other customized version of the WAM which enables high motor-encoder resolution

 

**The zero values dramatize the point that there is no external amplifier cabinet and no external PC controller. For those supplying raw battery voltage, the plus and minus leads are attached directly to the base of the WAM. Alternatively customers may choose to use Barrett’s laptop-style AC adaptor if they are not operating from a battery. The PC controller is an embedded Linux RTAI (now called Xenomai OS) system that weighs only 100 gms and resides inside the WAM. All real-time coordination between the embedded PC and the motor Pucks™ is done via an internal high-speed CANbus. While users are given access to both the CANbus and to a high-speed Ethernet cable, most users find it most convenient to use the wireless-Ethernet feature of the WAM. For those users who need totally wireless operation, the WAM base also has room for internal batteries.