channel CIO {
	out force(f, action(x)) == x
	out time(t, action(x)) == t + 0.01
}

channel C1 {
	in force(f, update1(y, m)) == y
	in mass(m, update1(y, m)) == m
	out acceleration(a, update1(y, m)) == y / m
}

channel C2 {
	in acceleration(a, update2(z)) == z
	out velocity(v, update2(z)) == v + 0.01 * z
}

channel C3 {
	in velocity(v, update3(u)) == u
	out position(p, update3(u)) == p + 0.01 * u
}