I (Thorsten A. Kern) receive on a weekly basis at least two, sometimes four to five wishes to supervise a thesis or external work in industry. Basically I am open to do so. However, there are some rules and criteria which I use to make my decision:
1.) There must be a strategic interest with the company and ideally already an established partnership on a professional basis.
2.) The relationship in the 3-way-collaboration has to match, I have to get to know the student and the company's supervisor
3.) We need to have capacity for the supervision, as especially for external master-thesis I do the supervision myself. And doing so I will involve myself significantly and not do the supervision pro-forma only. And even for Bachelor-thesis supervisions we have limited capacity with one external thesis per scientific staff-member at a maximum.
4.) The topic must match to our research (and not only to the title of my Institute). You can put almost every engineering topic unter the umbrella of "mechatronics", so make sure to match our running research with your request!
5.) Especially in case of a master-thesis a significant academic level and a real scientific challenge must exist in the tas.
6.) If there is a financial compensation by the company it must be not more than a small allowance for the effort. It must not have the level of a salary, this is not acceptable! The equality between students doing the thesis at the University and at an external company must be maintained. The only exception to this rule are students under the rules of a dual-studies.
If you feel that your specific case matches above criteria I am happy about getting in contact!
Furthermore I recommend to start organizing a supervision of an external thesis 8 to 12 weeks before start. We at our institute are almost always fully loaded with external supervisions. Spontaneously there is almost no chance that we can handle "just one more".