How to calculate the acceleration with only discrete blocks?

I would like to measure the acceleration out of the velocity, but I need to do so when the solver is in discrete mode and with a fixed step size of 0.02.

I tried using the discrete derivative block and discrete filter but I dont like the output I am getting.

Hope someone can help me find the optimal solution :)

I have attached the simulink file as well as the velocity.

[Samatha Aleti]

What do you mean by you do not like the output?