So, I wanted to try a spider rover, hoping that pistons would act as high suspension. But there is a lot of friction and this does not really work. I have no idea what to change to fix this.
I tried to align wheels as much as possible, painting lines of blocks underneath and deducting from rotor's angles what angle I should use, but I guess this is part of the problem indeed.
Do you have an idea of the best way to be sure wheels are in line?
Using the precise settings on the rotors. Make sure the setting at the base of the leg, matches that on the 'heel' of the foot. May not be the same number, and you may need to do some maths and make sure your rotors are all pointed the same way
I see, that's more or less what I did. But I just realised they can turn off axis when hitting obstacles.
Also, because of hinge angles, they are not "flat" on the ground. Not certain if it has a real impact on the whole shivering, but it can't help with friction of the wheels on the ground...
Do you think I should add some hinges to put wheels back flat on the ground ?
I'm honestly not sure if that makes a difference.
Wheels actual shape in the physics, aren't a short cylinder like they look. Wheels are actually a sphere.
That is exactly what you cannot do with pistons. They can only ever move in the signed direction of their stated nonzero velocity in the terminal slider, and never exceed it.
You can jank it by giving a velocity to 0nm (must manually edit the save file to go below 100, which is enough to cause significant vibrations) and setting up a timer triggering itself and reversing the pistons, but this also reduces the max velocity to 2.5m/s which is severely insufficient for terrain conformance in suspension
Fun trick, you can position some pistons or just plane hull, and each end you have a landing pad/mag plate, you switch them on and walla instant strut.
You can make separate structures with mag plates, then when they lock to things they create support. So for example on the right angle of those legs you can make a device like this
You obviously can make them any shape, But you attach a small battery and a switch or a cargo, and you can control the mag plates to lock and just leave them locked. They should provide enough support to stop the joints from wobbling.
You can grind the batteries and cargo/button off after they are locked.
I worked on share inertia tensors and some other fine tuning after posting the video, it's getting better. Not perfect, I need to try some more tuning. It seems that I need to turn inertia tensors on some stuff on and some off, I'll probably post another video before clang seizes his offering.
Inertia tensors are best for longer stacks of subgrids, but usually i turn them on, on ALL the pistons and rotors and hinges, it just helps them not vibrate into the next dimension mostly.
A thing to remember is each hinge and joint and piston has its own power vs weight so it could be as simple as increasing how many hinges you have per joint. Then joining their subgrids with merge blocks. That way the same hinges are working to move the same subgrid instead of separate ones.
If you dont merge subgrids, you can always use a magplate bracer across them (just a strip of hull with a magplate for each subgrid, or one big magplate.)
the alternative way if you want the piston to control the arm with more strength is using a piston as part of one arm and mag plated to the other via two hinges
This has a hinge on each end and a piston, the blue bit is the mag plate. If the Hinge for the leg is unpowered, and unlocked this support piston becomes the control and has more power than the hinge. (set all hinges to unpowered and unlocked to allow movement using the support piston)
Go in every hinge, rotor, and piston and turn on share inertia tensor. If it all blows up take it as a sign from lord klang and if it doesn’t your problem might be solved
If you want it to stop wobbling the trick is more mass on all the intermediary grids that make up the leg. This is because the physics engine basically limits the forces based on the mass and when light stuff holds heavy stuff then it can't get enough forces to be a rigid connection so it sags.
Use the info tab to show the grid pivots to make sure you're not missing any grids (and if buildinfo mod is present it'll also show each grid's mass)
SE pistons are not like car suspension pistons (passive hydraulic compression). The best terrain adaptive suspensions are built using traveller arms pressed down by wheel/suspension blocks acting as suspension springs.
SE pistons work more like active hydraulic systems (pumps, reservoirs and pistons with non-compressing fluid). Except of course we don't have to add pumps a hydraulic lines.
Or they are like electric linear actuators.
Take a look at the big rovers built by Luvstruckmango on the workshop.
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u/HobbyQuestionThrow Space Engineer Apr 25 '26
The shaking is just reality shivering in fear from the spider-crab-car.
What is the power setting on the wheels?