The Sport Devices ShockAnalyzer – shock absorber analyzer kit – allows users to build load cell based machine to analyze shock absorber performance.
As any Sport Devices product it features free software and lifetime firmware updates.
- Real-time data acquisition with any computer
- Shock absorber damping force and temperature acquisition vs. speed and travel
- See several graphs simultaneously: show or hide any curve.
- SpringAnalyzer functionality
How is it used?
Shocks are bolted into the dyno unit on the provided mounting locations. The stroke and motor speed is set to a chosen speed range (If you don’t have variable speed drive, speed range only can be select by stroke length setting.). The computer is set up to receive the data and the initial temperature is taken.
The machine is then started and the shock is cycled into the chosen velocity range where the data is sent to the computer. The computer can then display the data in a graphical method that will allow the operator to adjust the shocks accordingly.
For example, if a vehicle is coming out of the turns too tight the operator will run the shock on the dyno to check the setting. The shock is then rebuilt to loosen up the shock and ran on the dyno again.
With the proper expertise, the shock can be reinstalled on the car with the desired characteristics.
Shock temperature is measured using a thermocouple attached to the casing of the shock with a Velcro strap.
Shock performance can vary dramatically at different temperatures. With the temperature monitoring system, you can determine how your shock will perform under various temperatures. You can warm the shock directly on dynamometer.
Note: thermocouple is not included with the kit
- ShockAnalyzer DAQ
- 100mm Linear potentiometer – LINEAR VERSION
- Load cell (1000 kg default) – other sizes available on request
- RS232 cable and USB adapter
- Installation cables: mains plug, ground cable
Documentation and Software
Mechanical dynamometers are usually powered by 3-phase AC electric motors. The motors size and power is limited to its supply voltage. For applications up to 2hp, the motor can be powered by the usual mono-phase power source. Larger motors in the 2hp to 10hp range can be powered by 3-phase power source.
The motor can be connect to a variable frequency drive to allow the user to cycle his shock at variable cycles/minute to test diverse speed range. Variable frequency drive usually allow to connect 3-phase motors to mono-phase mains supply.
The output from the motor must be geared down, using toothed belt or gears. The max output shaft speed should be in the 300 to 400 RPM range.
Typical dynamometer installation
Piston – Crank Mechanism
This mechanism consists of a flywheel (crank), connecting rod, and piston similar to the piston-crank mechanism in an internal combustion engine. The flywheel have holes drilled to achieve different stroke lengths.
The disadvantage of using this mechanism is that it does not produce perfect sinusoidal motion in the piston, but having a longer connecting rod can compensate for this. Although it is not necessary to have sinusoidal motion, it does help reduce vibration.
The advantage to this mechanism is its cost effectiveness because there is less high tolerance machining required.
Scotch Yoke Slider
The scotch yoke has one advantage over the piston-crank mechanism. It produces perfectly sinusoidal motion.
It has two major disadvantages. It is expensive. The fine tolerance that are required for the slider will increase machining costs.
There is also more maintenance required with a slider joint.
Position Gear tooth and Stroke Length Selector
Dynamometer hardware use a n-1 gear tooth to measure speed and position, this part is supplied with the kit.
There are ten screwed holes located over spiral shape, connecting rod can be fixed in any hole to select stroke length. The longer the stoke, the greater the power needed on motor to move the shock absorber. At higher stroke, it is possible that the motor couldn’t move the shock absorber, thus we recommend to start at position 1 and increase it step by step.