If actually finishing a robot seems impossible to you, perhaps you need to take a fresh look at the task. Rather than stash the poor bot in the back of the closet (out of sight, out of mind), dust the little guy off and try a new tack.
First off, change the job in front of you. Rather than "finish this robot," determine the next subtask and think "get the wheels mounted." Naturally, this supposes that you already know the next subtask. If you dont, then immediately stop any physical work on your bot and make the next subtask "determine the remaining subtasks."
You have to get a line of subtasks defined that eventually will lead to a finished robot. Naturally, since your robot isnt finished yet, you cant actually know that youll get the list of subtasks correct, but you have to at least form a plan of attack. Otherwise, youll get stalled halfway there, set the bot in the closet, and...
Now lets suppose youve got your list of subtasks complete and you decide the next subtask is "mount the motors onto the frame." Before you even pick up a tool, think through the task and come up with at least four different solutions that could work for you. Im perfectly serious here; dont do anything until you can see at least four different ways of handling the subtask.
For the motor-mount example, you might come up with cable-ties to a frame member, foam tape to the frame bed, a U-clamp around the motor, or bolting the front of the motor to a specially designed L-bracket. Now begin imagining each solution in turn, mentally applying it to your motor and frame arrangement and checking, in your minds eye, how the proposed solution will play out.
You may decide that no one concept fills the bill completely, but the final solution could be a blend of two or more ideas. For example, you may determine that the cable ties would hold the motor to the frame, but allow too much side-to-side play. However, using foam tape to first hold the motor down, then adding the cable ties, could do the trick.
Even now, you arent ready to grab any tools. Now take a moment to try out a few different implementations of your solution. For the cable tie and foam tape example, you could certainly lay down a piece of foam tape, drill some holes in the frame material, and run a cable tie around the motor.
But further thought might lead you to a stick-on wire harness holder you saw once at a hardware store. The little gadget contains a square nylon bracket with a cable tie already attached. You just peel off a piece of paper on the underside of the bracket, revealing a square of foam tape already in place. This means all you have to do is clamp the motor onto the bracket, align the bracket properly on your frame, peel off the paper, stick the bracket down, and your motor mount is done.
Finally youre ready to do something physical. Run down to the hardware store, spend a couple of bucks on the wiring brackets, clamp the motors in place, and see how everything looks. Ideally, you should have a spiffy frame complete with two motors in clever little mounting brackets.
If you like how the mounts turned out, spend some time admiring what youve done. Im a firm believer in the "savoring" phase of robotics. Whenever you complete a subtask, take a moment to savor the results. Youve just made noticeable, tangible progress on your robot. Enjoy how that feels for a little while; you can always move to the next subtask later.
Ive used the motor mount problem as an example, but this technique applies to all elements of robot design. If you feel the urge to grab some tools, stop for a moment and think carefully about exactly what you intend to do. You can mentally erase and retry your ideas thousands of times, but erasing and retrying after youve drilled a few holes isnt so easy.
So if your robotic progress seems to have stalled, try this approach:
1. Break the job of finishing your robot into manageable subtasks.
2. Think up four approaches to solving the next subtask.
3. Mentally try out each approach and refine it; then choose the best one.
4. If possible, think out a better way of implementing the selected approach.
5. Do the work to execute the subtask.
6. Savor the results.
You can see that my technique is about one-sixth physical and five-sixths mental. Ill be the first to admit this approach wont work for everyone, but it helps me focus on getting a bot built. If youve been stalled for a while, give my method a try. It might get you back on track.
Keep on keeping on...