Hydraulic trainers
The two Hydraulic Trainers offer the ability to construct hydraulic circuits using the mounted elements, quick-connect hoses, and installed pump. The maximum flow and pressure produced are 2.7 GPM and 500 psi, respectively. Available hydraulic circuit elements include:
- 5 GPM analog flow meter
- 1000 psi analog pressure gauge (2)
- One-way flow valve (2)
- Variable flow control (needle) valve
- Pressure compensated variable flow control value
- One-way variable flow control valve (2)
- Manually operated, closed-center, 4-way directional control valve
- Solenoid operated, open-center, 4-way directional control valve
- Double-acting, single-rod piston actuator, 6 inch stroke
- Double-acting, single-rod piston actuator, 12 inch stroke
- Piston accumulator with gas precharge pressure gauge
- Sequence valve
- Pressure control valve
- Deceleration valve
- Fixed-displacement hydraulic pump/motor
Electro-Hydraulic Trainers
Two electro-hydraulic trainers combine digital data acquisition and control with electro-hydraulic elements. These stands offer experiments in the adjustment of electronically controlled values, system identification and control methods. The stands incorporate a BD101 signal conditioning card that functions as a servo valve driver with the option for input bias and scaling and a closed-loop proportional-integral controller. The card is normally connected to a PC via National Instruments hardware. The stand includes the following electro-hydraulic elements:
- D1FX proportional 4-way directional control electronic valve
- D1FH high frequency, two-stage pilot operated, 4-way directional control electronic valve
- DY3H high frequency, two-stage, 4-way directional control electronic valve
- BD15 high resolution, flow control electronic valve
- Double-acting, single-rod piston actuator, 12 inch stroke, with LVDT position sensor
Computer work station
Each electro-hydraulic trainer stand is connected to a workstation with a PC. The connection to the stand is via a National Instruments SCB-68 breakout box attached to a National Instruments PCI-6251 data acquisition card that resides inside the PC. The PCI-6251 has the capability of reading 16 singled-ended or eight differential analog inputs with 16 bit resolution at up to 1 MHz; the ability to produce two analog outputs with 16 bit resolution at up to 2.68 MHz; two 32 bit counters/timers; and 24 digital inputs/outputs. The data from the Electro-Hydraulic trainer stand is available to both MATLAB and LabVIEW environments for data collection and/or control.
Labs that Â鶹´«Ã½s perform with the hydraulic trainer include measuring flows and pressures associated with different hydraulic circuit elements and developing algebraic models of hydraulic elements. Labs that Â鶹´«Ã½s perform with the electro-hydraulic trainer (right) include working with servo valve electronics, dynamic system identification and closed-loop control.