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Question by dmaxwell · Apr 07, 2010 at 10:00 AM · physicsforcefollowforwardtrain

I want to make a train go round a track using physics?

Hi

I want to create a train and carriages (all independent when needed),I want the physics engine to move them round a track so I can stop start unlink so friction slows them down.

The track will run through a game environment curved and straight sections.

I thought about importing animation ,but the physics engine would give me more control

I need a simple physics model (sphere say) that is given a force along direction but is also fixed in a rail

any ideas?

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Answer by rd42 · May 06, 2010 at 01:05 PM

I don't know how detailed you will get in modeling your physics, but if you are including the wheels a track and some corners, the shape of the wheel is important.

Train Wheel Shape and Why

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Answer by BurningThumb · Aug 26, 2010 at 03:21 AM

If you need the train to move along a fixed path you can write a waypoint or path follow script using Rigidbody.MovePosition to change the position of the cars. If two cars need to link, simply reparent them to a single object. To slow a car down add a fractional multiplier to the speed that lerps from it's current speed to zero

  var speed = Vector3 (waypoint position);
        function FixedUpdate () {
        //move to waypoint
            rigidbody.MovePosition(rigidbody.position + speed * Time.deltaTime);
       // slow down
        rigidbody.MovePosition(rigidbody.position + speed * Time.deltaTime *Vector3.Lerp(speed, 0, time););
        }

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