My task is: I need to build a very thin scale (like a bathroom scale), less than 8mm in thickness total, and needs to work even if placed on rough terrain (so it needs it's own bottom and top). The total load will not exceed 10kg. I've been trying to look for the correct force sensors to use but I haven't found anything too attractive. Load cells are large and expensive, strain gauges look promising but I'm afraid of bridge balancing issues, and force sensing resistors are garbage because of drift. I need accuracy of +/- 5% or better, so does anyone know any sensors I could try? Thanks!