Below is a link to view my rendered tennis ball and bowling ball in the album ‘Bouncing Balls’ on my Flickr page:
Whilst trying to come to grips with using Maya, my classmates and I were tasked with animating a bowling ball, a tennis ball, and a bouncy ball. Whilst we’d previously been asked to create a basic bouncing ball, I had some knowledge in performing this task but the specific characteristics of each ball’s material influenced how the object behaved; this meant that I was required to watch and understand each of their individual traits in terms of movement.
As I had initially struggled with the first ball task, I recapped on how to bounce a ball by looking at tutorials online, but also looking at new tutorials explaining how to ‘squash and stretch’.
I noticed the best approach when initially animating a generic ball, is to set a key frame (whilst selecting Translate X, Y, and Z) as the ball is suspended in the air (this allows the animator to realistically depict the physics of the ball after this point), then set a key frame at a later frame, after the ball has touched the ground, then repeat this process for the remainder of the bounces. After doing this, I’d open my graph editor, look at translate Y, then manipulate my tangents so the movement of the ball would be more fluid as it moved on the spot. In order to eventually get my ball to move forward, I would go to my Translate Z axis on my graph editor, delete all points but the first, find the point where the ball would stop moving, then I’d move the ball forward to point where I’d like it to stop, then make I’d select (Shift+W).
For my bowling ball, I found a video which showed a basic bowling ball as it had been dropped from about chest height, and noted that the top of it’s first bounce had met a decrease of below 50%, whilst the top of it’s next bounce was below 50% of the first. I also noticed how the bounces of the ball itself spanned over a length of around 1 foot, then rolled for around 3 feet. Whilst making my animation, I tried to mimic this.
Below are two screen grabs of my bowling ball work; the first at it’s highest point, the second as it initially hits the ground.
Below is the rendered version of my bowling ball. As a final touch to my work, I decided to add a light source from the ground, and a spotlight from the top left of the scene. This made viewing the ball easier. I also added a marble texture to the ball to give it a similar appearance to an actual bowling ball, and added a wooden texture to the floor.
Below is a video I used as a reference for this task:
Similarly to how I handled my bowling ball, before creating my tennis ball I watched numerous videos to understand it’s physics and characteristics. From these observations, I noted that the ball would commonly make approximately 7 bounces on it’s own before stopping completely. After being dropped from head height, the ball reached more than 50% of it’s first bounce, then gradually started to decrease in it’s bounce by about 50% throughout the remainder of it’s bounces. I also noted that the ball bounces the distance of around one metre and a half, then rolled for around one metre. When initially approaching this ball, I faced errors with my values, meaning my ball would occasionally be stuck in the ground; I corrected this by starting the scene over again. Furthermore, when initially starting this tasks, my tangents were far to high, and to impractical to manoeuvre; I corrected this by lowering the over all height of the ball whilst reattempting the project in a new scene.
Below are the screen shots of my tennis ball project.
For this task, I once again used textures for both my ground, and my ball to slightly mimic what they may actually look like. I also added a light source from the ground so that the scene was easier to view whilst it was rendered. Below is an image of the rendered ball. Unlike my last rendered image, this scene did not have a spot light; this is because I wanted to experiment with what light sources I like best.
Below is one of the videos I used as a guide for helping me create a more realistic tennis ball
My bouncy ball was by far the most energetic ball to animate. It moved significantly quicker than the other balls due to it’s rubber material. Whilst watching a particular video of a bouncy ball in motion, I noticed how rapidly the ball would bounce as it became closer to stopping completely; this made it far more erratic than both the previous balls. I noted that the ball bounced over the period of about 9 seconds, and made around 6 bounces in the space of about 3 seconds, then around 10 bounces in the space of about 3 seconds, then around 12 bounces for around 3 seconds. I also noted that the ball made inconsistent bounces due to it’s material, and that each bounce was around 25% lower than the previous.
Whilst the ball in the video travelled the length of a doorway, I decided to position my ball in the one area; after implementing squash and stretch, I liked the appearance of the ball in the position in which it was. Whilst previously attempting to implement squash and stretch, I felt like the attempt was not very successful as the values of the ball changed by the end of the scene; this meant the bounces were less believable. To correct this problem second time round, I recorded my values more thoroughly and set my ball to it’s original values throughout different times of the scene, whilst using consistent ‘Squash’ and ‘Stretch’ values.
Below are two screen shots of my bouncy ball as it’s in motion. The first shows how the ball appeared as it was stretching, whilst the second shows how the ball appeared as it was being squashed.
Below is a rendered image of my bouncy ball. Similarly to both my previous bouncing ball scenes, I added a Lambert for both the ball, the ground to create texture.
Below is one of the videos I used to help me with recreating a more realistic bouncy ball.
Here are some of the tutorial videos I used to help me bounce my ball on Maya.
The video below was significantly useful in helping me create my bouncing ball and utilising squash and stretch.