A02.13 PD - Robotic Arm.DOCX

ROBOTIC ARM FOR UNMANNED GROUND VEHICLE (UGV)

Product Description

Background

The US Army Corps of Engineers (USACE), Engineer Research and Development Center (ERDC) is in need of a robotic arm to meet existing project requirements. The robotic arm will be integrated into an existing Unmanned Ground Vehicle (UGV) to be used for sensor deployment in a remote inspection application.

The USACE is responsible for the operation and maintenance of flood control structures within the United States. These flood control structures include dam facilities with pass through tunnels and flood control gates. Many of these facilities are aging and inspection for degradation is required on a periodic basis. The periodic inspections primarily focus on the condition of the flood control gate structures at the distant end of the tunnels. An example drawing of the outlet works can be seen in Figure 2.

The tunnels range in size from less than 10 feet in diameter to greater than 25 feet in diameter. The gates vary widely in structural design and scale and range from on the order of 10 feet in height and 6 feet in width to 20 feet in height and 10 feet in width. Figures 3-9 illustrate a variety of gate designs.

Current inspection techniques require human inspectors to enter the tunnels for manual visual inspection. This exposes human inspectors to potential hazards. Development of robotic telepresence inspection tools are desired to mitigate these risks.

The ERDC maintains an existing Argo J8 XTR amphibious unmanned ground vehicle (UGV) (Figure 1) which is being used for the development of this robotic inspection platform.

Figure 1: Robotic platform CAD

Figure 2: Typical earth dam tunnel diagram

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Figure 10. Dimensions for the volume allocated to robotic arm.

Figure 11. Orthogonal view of arm volume placed on J8.

The robotic arm will need to be able to attach to the existing Argo J8 XTR platform in a manner that minimized the impact to the platform’s operability and functionality. The expectation is that the arm will mount in the forward deck area of the J8. The arm will need to account for the payload capacity and balance of the UGV during amphibious operations. The robotic arm must include enough Degrees of Freedom (DoF) to allow for adequate inspection of the gate structures. Given the variety of gate structures across the USACE it is expected that there will be need for significant versatility in end effector maneuverability.

The robotic arm shall have the following components:

HARDWARE SPECIFICATION:

· Maximum weight no greater than 150lbs

· Arm must collapse into volume of 40”w x 54”l x 24”h

· Arm must expand and reach the end effector throughout a minimum volume of 10’w x 5’l x 15’h

· Minimum vertical reach no less than 15ft from ground level

· Minimum horizontal reach no less than 5ft left and right of center

· Must be powered by 48VDC and not exceed 100A

· Must support minimum 10lb payload at end effector

· End effector must include mounting capability along with passthrough power and data line wiring for Ethernet communication

· Ingress protection rating must be no less than IP67

· Arm must be compatible with Robotic Operating System (ROS) v1.

· Vendor must provide Unified Robot Description Format (URDF) file as well as ROS node that publishes accurate positional information for each joint (the joint state information should follow standard ROS methodologies for a joint state publisher including sensor messages that includes joint name, position, velocity, and effort at minimum 10Hz update rate)

· Arm kinematics must be reported with minimum sub-centimeter accuracy at each joint

Delivery Fully integrated arm shall be delivered to the Engineer Research and Development Center (ERDC) at 3909 Halls Ferry Road, Vicksburg, MS 39180 six (6) months after receipt of order.

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