Technical information

DRV Final Evaluation Report

Plan of Action

• Install and implement a new hydraulic and electronic control system that

exhibits reliable and controllable motion.

• Make reasonable structural repairs to the azimuth joint and short arm sections.

• Perform the repair with a goal of one year of usable service for the purpose

of evaluating the machine concept.

Work on the rebuild of the DRV was conducted at the AHMCT Research Center and the

Caltrans Equipment Service Center. Upon completion of work on the DRV,

demonstrations were given at both the AHMCT Research Center and the Caltrans

Equipment Service Center to gain approval for release for field operational testing and

evaluation (see attachment A). Approval was obtained for release on July 31, 2000.

The DRV underwent service for the first 1.5 months after being delivered to Caltrans

District 8 in San Bernardino. There were several problems with the truck equipment

including the engine brake, fuel sensor, side mirror, and hydraulic hoses. Once the

repairs were completed in mid September, 2000, the DRV began the field operational

testing and evaluation phase.

Description of Machine and Operation

The Caltrans/AHMCT Debris Removal Vehicle (DRV) is an operator controlled garbage

collecting manipulator with limited automatic modes to assist in the most tedious tasks.

The DRV consists of a dual steering Volvo-White truck equipped with a 10 yard garbage

bin and a robotic arm consisting of an open kinematic chain of six revolute joints. The

operations are controlled by a joystick and switches mounted on an operator control

console. In normal operation, the operator programs preset manipulator locations into the

machine. These preset locations are activated by the joystick pushbuttons. In the field,

the operator deploys the manipulator to a preset location by depressing the appropriate

button. Then, the joystick is used for fine adjustment of the manipulator in order to grab

the debris. The bucket is then closed. When the operator is satisfied that the payload is

secure, the automatic dump action is initiated with a specific button combination. The

manipulator repositions itself over the compactor entryway, releases the garbage, and

repositions itself again to be ready for the next task. The operator can then reposition the

vehicle and restart the collection process again. If the operator determines that the

garbage in the body needs to be compacted, the entire compaction cycle is initiated by

another button combination from the joystick.

Evaluation of User Interface

The design of the operator’s control interface had to address a wide range of

considerations. The machine is designed to be operated from either side of the cab and

performs tasks on either side of the machine. In addition, the workspace of the arm must

be versatile requiring the operator to be able to view a large area. This is difficult for an