# Event-Based Motion Analysis

Motion analysis is a tool to help us simulate and analyze the movement of the mechanism in the assembly. In the motion analysis, we can include the effect of various kind of element, such as forces, springs, dampers, and friction, etc. It could also inherit, constraints from SOLIDWORKS, as fixture, and mate condition.

Motion studies have two types of study: time-based and event-based.

Time-based: Describe the response to time changes in motion elements, by timeline and keyframe. Keyframe to save the position/properties differences of selected component, and store the time and event in the timeline

Event-based: Event-based motion can automatically generate time sequence for element change, defined with a set of motion actions resulting from triggering events.

A trigger-action event you can imagine it as flipping a light switch. Flipping the switch is the trigger. The light bulb lighting up is the action. In event-based motion, you could set different kind of combinations of trigger and action. Below is a list of categories:

 Triggers: Time, Sensors and Tasks Actions: Motors, Forces and Mates

In my example, I had set 2 kind of triggers. First 2 tasks are using Time as a trigger. The Rotating Arm and the Valve will start moving, at 0s and 4s correspondingly.

Sensors are the next set of triggers. For example, I have set the sensor location on the diagonal face, highlighted in blue as shown below. Trigger is when the ball reached the select face.

The resulting action is to rotate a model with 1,2,3 label, which is hidden in the column under the sensor.

Furthermore, I could add 3 different sensors, to control the rotation degree of the labelled model, displaying the ball’s number that sitting above the sensor.

During calculation of the motion, when the sensor triggered the task will enter the starting and ending time automatically.

Finally, the event-based motion simulation simulates the interaction between the balls and the rotating action. Then utilizing trigger and action task provide us the result of the ball’s order sequence as 2 > 1 > 3.

Event-based motion analysis require with SOLIDWORKS Simulation® Professional added in.

Written by Benjamin Cheung, Intelligent CAD/CAM Technology Ltd.