FRC Motor Mounting Template

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My name is Bar Danino. I am a mechanical engineer in the defense industry, but my entry does not come from my official job. In my spare time I am a mentor for a high-school robotics team participating in the FIRST Robotics Competition (FRC). I have been involved with this program for over a decade.In FRC, teams of high-school students work to build a robot to participate in a certain game that changes every year. The games contain many tasks, some simple and some complicated, such as shooting foam balls, lifting heavy crates or climbing on poles. Robots vary in size but tend to be equivalent to the average in weight and height. For some examples you may visit my team’s website: https://www.spikes2212.com/robotsIn this competition, teams use a variety of PMDC motors, but often lack the equipment or funds to machine perfect mounting holes for them. In fact, some teams have no more than a handheld drill. I created this product to help such teams drill fairly accurate mounting holes for their motors, in a way that doesn’t require high levels of technical skills (in other words, in a way that a high-school student with little experience could easily perform).There is a large variety of PMDC motors available for use in FRC, but since they are (mostly) designed specifically for this competition, they are highly standardized. The same hole pattern (location, hole sizes vary) could be used to mount all large FRC motors (CIM, Mini-CIM, Neo, Falcon 500, PG91/188). Small FRC motors have different hole patterns, but almost all of them are used in combination with the VexPro VersaPlanetary gearbox, which shares a hole pattern with the large motors.This product, the FRC motor mounting template, allows teams to recreate this hole pattern easily with a handheld drill. The outer diameter of the template is similar to that of most large motors, so teams could use it to locate positions where their motor would fit. To use the template, its flat side is placed on the surface to which the user wishes to mount the motor. When a position is chosen, the user will use a 2mm drill bit to make a hole in the surface through the hole in the center of the template.The template is then removed, and the hole is expanded using a 6mm drill bit. The template is reversed, and its protruding pin (the locating pin) is placed into the new hole. This guarantees that the mounting holes would be correctly placed relative to the center, where the motor shaft will pass. Once the template is placed, the mounting holes are drilled with a 2mm drill bit, through the holes in the template itself.The channel around the base of the locating pin ensures that the template could be laid perfectly flat against the surface. The large opening in the side of the template will be used to hang the bracket off a hook or a string, to help prevent it from getting lost.Now, why print the template? Why not machine it? Most teams operate on a tight budget and printing this template in a home FDM printer would be a lot cheaper than machining it. Also, as previously mentioned, most teams don’t have access to quality machining (or any machining, for that matter). Then again, a lot of teams either have a 3D printer or are located in the same city/region as a team that has a 3D printer. That makes this printed template much easier to obtain than a machined one.FRC teams have a strong sense of community, and are encouraged to cooperate with their competitors and assist their competitors. Because of this, I believe a single team might print dozens of these and distribute them among many other teams. Perhaps my team would do it. The cost would be tiny, and it would allow weaker teams to make great improvements in their design abilities, especially after COVID during which many teams lost a lot of knowledge as veteran students graduated without younger students having the opportunity to learn from them.That is, essentially, the impact statement of this product: it would allow a large number of teams to build better, more effective robots, with little-to-no cost.Some technical details: the template has a volume of 8.9 cm. Its outer diameter is 63.5mm and its height is 8mm. It is to be printed on its flat size. Printing material is unimportant, though PLA is most likely to be used due to its commonality and ease of use. No special layer width/nozzle diameter are required (the common 0.2mm layer and 0.4mm nozzle will suffice). At least nine units could be printed on almost any home printer.