Download mrf_thesis - Virginia Tech

Figure 1.1: Case CX-160 and team members
1.2 Technical Challenges
Converting a 16-ton hydraulic excavator to teleoperated control presents a variety of
technical challenges. Design decisions associated with by-wire hydraulic control,
software development, telemetry, operator feedback, system durability, and safety
significantly impact project success.
Improper modification of high pressure hydraulic systems may result in human
injury and machine damage. Therefore, safety is a high priority when working with
hydraulic components. The proper selection and placement of hydraulic components is
critical to optimal by-wire control. Consequently, hydraulic system flow rates, pressures,
and system response require close attention [2].
Robustness and optimization in software design are essential to reliable real-time
control. Software development must resolve errors and failures while still maintaining
stability and functionality. Control data must be sampled, packaged, transmitted,
deciphered, and executed efficiently, frequently, and with minimal delay. Computational
and control hardware should be capable of executing developed software and expanding
for future software development. The telemetry solution must be capable of supporting
system bandwidth and be resistant to interference.
The operator must have an understanding of the work environment in order to
make control decisions. Thus, sensors need to be placed on the vehicle or at the work
2