Welcome to the mid-beta2 DevBlog!
We hope you’re enjoying the Beta so far!
Today, we'd like to talk about Kits. Kits allow you to create reusable parts of a robot and share them easily! Kits can be as simple as a single part with perfectly tweaked properties or as complex as an automated segment of a walking centipede with multiple sensors, programmed CPU, and mechanical legs!
Kits are a relatively new addition to Main Assembly, and not yet introduced through the tutorial system, so we’d like to use this opportunity to step through the creation and use of a simple kit!
So how do we go about making one? Here’s a little starter bot we’ll use to test stuff:
The plan here is to make something that acts a little bit like a servo but can spin a full 360 degrees, and can either be programmed with a target angle or a constant rotation rate. This is a useful concept which we don’t (yet) have a dedicated built-in part for, a perfect kit candidate!
First things first, a Kit has a root part which dictates which bit of it attaches to bots. This can be anything, but it’s often convenient to start with something simple to act as an anchor piece!
Next, we’ll build a tiny chassis to support the other parts we will need for this experiment - a CPU and a motor!
Add the remaining functional parts, and we’re nearly done!
The final steps are to program our proto-kit’s CPU: we’ll add some inputs, a PID controller, and some fiddly math to make sure that it handles the motor’s current angle wrapping around from -180 to +180 degrees. Looks a bit messy, but the advantage of kits is that once the work is done someone else just needs to use the inputs and not worry about the inner workings!
We added a Reset input in addition to Target and Speed, so you can clear any internal state and put the motor back to its starting position.
Alright, time for a quick test! In the docking station, we hook some inputs up to a wrapping sum node and then feed that into the Target input on the proto-kit CPU!
Add a quick indicator and all seems to be working as intended!
All the functionality is implemented, now we just need to turn this chunk of robot into a Kit!
Select the root of the kit, in this case the attachment part we placed right at the beginning, and bring up the radial menu (E by default). Under Advanced, click New Kit.
The part plus all its counterparts are selected and isolated from the rest of the robot to form the new kit.
You now get to name your kit, add some notes, assign a category, and take a picture that will be used as an icon and default image if you upload the kit to the Steam Workshop.
Now when you bring up the Kits menu (Tab by default) you can see your new kit under the assigned folder. Clicking on the little cogwheel allows you to delete or move the kit or upload it to the Steam Workshop for others to use. Clicking the kit icon itself allows you to place copies of it on the currently open bot, just like a regular part!
Once kits are placed, they are unpacked into collections of parts that can be edited, reprogrammed, and tweaked.
And now we have a motor that can turn at constant rate but will remain fixed around its current angle - perfect for implementing a certain kind of mechanical walker! This simple and somewhat wobbly strandbeest uses two of these kits to provide power to its legs. Notice how the two primary metal bars near the middle rotate in lockstep with 180° offset – pretty rad!
Thanks so much for reading! Keep sharing your creations with us and we’ll catch up with you next week!
https://store.steampowered.com/app/1078920/Main_Assembly/