Grate, Rake, and Kevlar Hinge Doors in RASSOR Drum for Improved Efficiency and Performance

grabcad

Design Summary: The design purpose is to meet the design requirements from the competition description and the included paper. The design goals are as follows: Meet the dimension requirement Manufacture-able and functional Last for at least 5 years Prevent icy regolith (equivalent to damped sand on earth) from sticking to the scoop Successfully exclude rocks of a certain size from entering the bucket Maximum weight of 5kg Based on this, I've created this design. The design is able to: prevent rock larger than 1cm in diameter from entering eliminate cohesion of icy regolith prior to entering the scoop retain what's inside the bucket when on a trip back to the lander for about 8.5 minutes all parts expected to wear out will be replaceable manufacturing is possible, as explained in the pictures assembly is possible, as seen in the gif Structural integrity The weight of the bucket in total is about 4.5kg. The dimension of the drum has already fulfilled the dimension requirement, with max diameter of 450mm with scoop, 340mm without scoop, length of 360mm, and maximum engaged scoop at any given time 175mm. It will be able to collect AT LEAST 22L of regolith in one mining cycle, with AT LEAST 70-80% full. To make it reach at least 70-80% full I use doors to prevent regolith from falling out, the doors only located in 1 or 2 scoops in each segment. To keep the mining cycle fast, the other scoop that has no doors will have a larger outlet, so it catches more regolith as it rotates backward, thus creating faster unloading on that scoop. Will the mining cycle be faster? I don't know, but using this system will allow it to be more effective, as regolith lost is minimal, with still three scoops on each segment, keeping the time of mining fast. It uses markers so the operator can control the position of the bucket for maximum regolith volume retained. The scoop that has no doors will not function as well as the one with doors when RASSOR is mining. The reason is that when it reaches about 30-40% full, regolith will start to fall into the scoop cavity, so the regolith will not be much since the way is blocked by the falling regolith from the inside. Thus, to add more regolith when its already 40% full, the scoop with doors will have a crucial role, as the scoop cavity will not be filled with regolith from the inside, keeping digging capacity for that scoop just like normal, until its about 70-80% full after mining about 10 minutes. Beyond that, the openings of the door will be limited by the regolith surface, making it less effective. As an additional information (because it's not mentioned on the presentation uploaded): the scoop can cut 5cm deep, but cutting it 5cm in one scoop will jam to increase the volume, the drum circle line should've been tangent to the scoop curve will the doors get stucked by regolith? No it won't, see my discussion with Sava Savov on the comment section After thinking of it for a while, the doors might also have the ability to unload. When its about 60-80% full, the doors won't be fully closed when it rotates backward and reach the surface of the regolith inside, thus some of the regolith will get through the door and will be able to unload through the scoop with doors. But thats not the case when its almost empty, in this case the scoop without doors will unload the regolith File including: STEP and STL file is compiled into one rar STL also available to download in single part renderings explanation pictures animated gif the gif animation in mp4 format Reference: Mueller, R.P., Cox, R.E., Ebert, T., Smith, J.D., Schuler, J.M. & Nick, A.J. 2013. Regolith Advanced Surface Systems Operations Robot (RASSOR). IEEE Aerospace Conference Proceedings. Wilkinson, A. & DeGennaro, A. 2006. Digging and pushing lunar regolith: Classical soil mechanics and the forces needed for excavation and traction. Journal of Terramechanics 44 (2007) 133-152 Illustration: The videos listed below is just to illustrate the reason why I choose the design, all of the videos are not my creation. https://www.youtube.com/watch?v=cgI5EzcpK6s&t=456s https://www.youtube.com/watch?v=Q675gKNp6zs&t=22s https://www.youtube.com/watch?v=C-b-7BYygFs