临时解决办法：修改laya.physics.js里的__proto.PostSolve方法：
__proto.PostSolve=function(contact,impulse){
//新增冲量
//contact.impulse = impulse;
contact.impulse = {}
contact.impulse.normalImpulses = [impulse.normalImpulses[0], impulse.normalImpulses[1]];
contact.impulse.tangentImpulses = [impulse.tangentImpulses[0], impulse.tangentImpulses[1]];
}
