Spring Wooden Toy: SOLIDWORKS Tutorial
For this SOLIDWORKS tutorial, I wanted to design a wooden toy that involved the use of springs. The springs would be added within a motion study and would cause the flowers to pop out of the plant pot base when pressed. To mimic this action, I used a linear motor with distances. The assembly parts for this tutorial are available to download here if you would like to follow along.
I began the tutorial with the creation of the toy assembly to take you through the mates in place. The mates I added were used to position the parts, but also to help the motion study run more smoothly by holding parts in place. I have a floor part to sit the plant pot part onto but also to catch the flowers when they spring out of the pot. Finally, I used 3 small wooden discs within the plant pots spring cavities for the flower stems to stand level on top.
I used 3 types of mates for the flowers, the first is a concentric mate to hold the flower concentric to the plant pot hole, the second was to hold the flowers stem bottom face onto the top face of the spring disc, and the third was a parallel mate that kept the flowers forward facing while I was adding other mates, just in case they moved while I was adding other mates. Once all my mates were added, I renamed them easier to distinguish between. I’m named the concentric mates of the flowers, the flower’s name plus stem. The coincident mates for the flower stems were renamed to the flower name plus temp mate, as these would be temporary mates in my motion study. Then concentric mates for the spring discs were also renamed with the flower name they were below plus spring. Doing this makes a slightly fiddly motion study more clear, especially when mates play a role in the study. I made the temporary axis in my assembly visible to use for motor directions.
I used a motion analysis for my study type, and disabled the playback of view keys so that existing orientation and camera views key point views were ignored in my animation. Under the settings cog icon, I checked the use precise contact box, I often use this option for my studies, this makes the contacts in my study more precise, but on the other hand it can also slow down the calculation time. Then I added the most important element, gravity! along the Y axis, ensuring everything fell naturally. Then I added solid body contacts, ensuring all parts are selected, this is equally important to ensure all the parts interact with each other. With section view on to see the plant pots spring cavities, I used linear springs, and selected my spring parameters which are between the bottom face of the spring disc, and the bottom face of the cavity. You should get a little preview of what the spring looks like, but this is just a temporary visual.
I used motors to mimic the effect of pressing onto the flower and then releasing it to spring out of the toy. Changing the motor type to linear motor, I needed to choose a component, then I used the flower stems temporary axis for the motor direction. I needed to flip the direction downwards and change the motion type to distance. With this option, I could input 14mm for how far the flower was pushed down into the plant pot, the start time for the motor, and the length of time it takes to push the flower down by 14mm. This process was repeated for all of the flowers, but at different intervals, to space apart the movements. Once all the motors are added, I’m renamed them with each flower name, making it easier to distinguish between them.
Dragging the mates window up to see all of the mates in play and the three motors, I had to select the parallel mates holding the flowers parallel to the plant pot, and the 3 coincident mates holding the spring discs still and suppress them all at 0 seconds. I then began turning off my motors for each flower after 0.6 seconds from each motor turning on, to ensure they each ran for the same amount of time, this just helps me visually to see when my motors finish. It was at the end point of each flowers motor that I also suppressed the flower stems concentric mate that held the flower concentric within the plant pot hole. By keeping the concentric mate active during the time the motor is on, I am stopping the flower from tilting within its hole which speeds up the study calculations, but this needed to be switched off to stop the flower landing back into the hole, instead allowing it to fall onto the floor. The coincident mate for each flower is supressed at the start time of the flower motor that is moving, this mate keeps the bottom face of the flowers stem coincident to the top inner face of the spring’s cavity, this needs to be supressed here to allow the flower to be pushed down. Finally, the concentric spring mate for each spring disc remain active throughout the analysis, to keep the disc upright throughout the analysis, just to help the calculations run more smoothly.
When I select the calculate icon, I have the playback while calculating option on so that I can watch the result of my analysis as it calculates, just in case there are any issues, or things aren’t moving the way I need them to, I would be able to cancel the analysis and make any changes. Once the analysis has finished running, I used the SOLIDWORKS Visualize add in to export the motion study directly in to Visualize to render a final animation which you can watch at the end of the tutorial.